status and results from opera tomoko ariga lhep, university of bern on behalf of opera swiss groups...
TRANSCRIPT
Status and results from OPERA
Tomoko ArigaLHEP University of Bern
on behalf of OPERA Swiss groups of Bern and ETHZ
OPERA
bull Aiming to prove the flavor-mixing neutrino oscillation hypothesis by appearance methodndash Appearance of new flavor nu-mu nu-taundash Search in the region predicted by other disappearance
experiments
bull Direct observation of nu-tau events in nuclear emulsion detectorsndash Sub-micron resolutionndash 125 kt of target mass
t (FL ~500mm)1ryvertex
non-munt CC interaction
CNGS beam
lt E gt 17 GeV
L 730 km
( e + e) 087
4
prompt negligible
Expected interactions in 5 years ~25400 CC + NC
~170 e + e CC~125 CC (m2 = 25 x 10-3 eV2)
L = 732 kmCERNLNGS
Tflight = 244 ms
CERN
LNGS
730 km
~10 tau decays are expectedto be observed
after 5 years running
102 cm
125 cm75 cm
neutrino
OPERA target
ECC brick
OPERA Brick = 57 nuclear emulsion films interleaved by 1 mm thick lead plates
OPERA Film = 2 emulsion layers (44 m thick)
poured on a 205 m plastic base
OPERA Film times 57 plates
Lead x 56 plates
OPERA Film
Lead plate
1mm03mm
The OPERA target consists of
about 150000 bricks
Total target mass 125 kton
OPERA detectorSM1 SM2
VETOTarget area Magnet and RPCs
PT Brick Manipulator System
Extract and validate the ECC brickDevelop and send to scanning labs
Parallel analysis of ECC bricksbull Validated bricks are sent to the scanning labs
ndash 10 scanning labs share the scanning
bull Swiss scanning station scanned the highest number of bricks in Europe for 2008 run
To Japan
Padova
To MosccowLHEP
GS
Scanning labs Nagoya (JP)LHEP Bern (CH)Napoli Bari Salerno Bologna Padova Roma Frascati (IT)Dubna (Ru)
Swiss scanning station in LHEP Bern
bull Largest scanning group in Europendash 10 physicists (Bern + ETHZ)ndash 5 microscopes with full-automatic plate changerndash Capability to scan more than 15 bricksweek
0
2E+18
4E+18
6E+18
8E+18
1E+19
12E+19
14E+19
16E+19
18E+19
18-J
un
28-J
un
8-Ju
l
18-J
ul
28-J
ul
7-A
ug
17-A
ug
27-A
ug
6-S
ep
16-S
ep
26-S
ep
6-O
ct
16-O
ct
26-O
ct
5-N
ov
inte
gra
ted
po
t
Total 1781019 pot
18kV cable repair
MD
PS magnet exchange septum bakeout
MD
SPS timing faultvacuum leak amp magnet exchange
CNGS maintenance
SPS extraction line Magnet ground fault MD
CNGS maintenance
Nominal 45 1019 potyr for 5 years
Beam to CNGSLHC FT MD
Beam to CNGSLHC FT
Beam to CNGS MD
2008 CNGS run (18 June - 03 Nov 2008) first physics run
Located neutrino interactions
Brick 81813
Brick 24487
Emulsion gives 3D vector data In ECC brick we can reconstruct vertices with an accuracy of a few micron(The frames correspond to emulsion films The other colored line shows the extrapolation of measured tracks The color indicates the Z-depth in the module)
1 cm
Brick 82372
(animation)
Status of event location in ECC for 2008 run
Scanning for 2008 run will be completed by September 2009
with muon without muon Total
Events in target 1663
Bricks developped 959 218 1177
Vertices located in ECC 678 119 797
Vertices in the dead material 17 4 21
Impact parameter distribution
mm
Analysis for located eventsbull Goal of 2008 run
ndash Check nu-tau detection efficiency by detecting charmed particles (similar life time and mass with tau)
bull Charm particles are produced in nu-mu CC interactionsbull ~23 events are expected for ~1200 nu-mu CC events
ndash Nu-tau detectionbull 07 event is expectedbull No clear candidate up to now
Particle Mass (MeVc2) Life time (10-15 s) cτ (micron)
τ 17769 291 871
D+ 18693 1040 3118
Ds+ 19682 500 1499
Λc+ 22865 200 599
Charm candidate 51284 (di-muon event)
kink
x-view
1ryvertex 4 mm
13 mm
flight length 1330 micronkink angle 209 mradIP of daughter 262 microndaughter muon 22 GeVcdecay Pt 046 GeVc
1ry muon
daughter muon
(animation)
Charm candidate 72853
Both 1ry vertex and decay point are in lead plate
muon
Lead plate
1ryvertex
IP wrt muon(micron)
IP wrt decay point(micron)
Momentum(GeVc)
Daughter1 370 05 13
Daughter2 135 04 23
342 micron
muon
(animation)
muon
muon
Lead plate (1 mm)
Hypothesis (1) D0 candidate
Hypothesis (2) t candidate
minimum kink angle 312 mradmuon momentum 17 GeVcPt gt 53 GeVc
Excluded by Pt Pt gt maximum decay Pt of t (09 GeVc)
1ryvertex
1ryvertex
D0
t
Charm candidates
Expected ratio Number of candidates
1-prong 37 5
2-prong 30 4
3-prong 19 1
4-prong 7 1
Analysis ongoing for located ~700 nu-mu CC eventsUp to now we have collected 11 candidates
13 events are expected for 700 nu-mu CC events(23 events are expected for 1200 nu-mu CC events)
Activities of Swiss group in OPERA analysis
bull Common for all labsndash Decay searchndash Kinematical analysis
bull Unique to Swiss groupndash Study of hadronic background for taundash Gamma detection energy estimation π0 reconstructionndash MC studies on tau and charmndash Electron ID energy estimationndash Low momentum muon IDndash Development of 3D display for event analysis
Study of hadronic background for tau
bull Motivationndash Hadronic re-interaction is a major source of background for hadronic decay
channel of tau Monte Carlo has large uncertainties (MC says a hadron track of 1mm length creates a decay-like topology with a probability of 10-5)
bull Methodndash Analyze the particles from neutrino interaction vertices Measure the number
of decay-like interactions and study Pt distribution etc
tau hadron1ryvertex
non-mu non-mu
Hadronic re-interaction background from nm NC interaction
nt CC interaction
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
OPERA
bull Aiming to prove the flavor-mixing neutrino oscillation hypothesis by appearance methodndash Appearance of new flavor nu-mu nu-taundash Search in the region predicted by other disappearance
experiments
bull Direct observation of nu-tau events in nuclear emulsion detectorsndash Sub-micron resolutionndash 125 kt of target mass
t (FL ~500mm)1ryvertex
non-munt CC interaction
CNGS beam
lt E gt 17 GeV
L 730 km
( e + e) 087
4
prompt negligible
Expected interactions in 5 years ~25400 CC + NC
~170 e + e CC~125 CC (m2 = 25 x 10-3 eV2)
L = 732 kmCERNLNGS
Tflight = 244 ms
CERN
LNGS
730 km
~10 tau decays are expectedto be observed
after 5 years running
102 cm
125 cm75 cm
neutrino
OPERA target
ECC brick
OPERA Brick = 57 nuclear emulsion films interleaved by 1 mm thick lead plates
OPERA Film = 2 emulsion layers (44 m thick)
poured on a 205 m plastic base
OPERA Film times 57 plates
Lead x 56 plates
OPERA Film
Lead plate
1mm03mm
The OPERA target consists of
about 150000 bricks
Total target mass 125 kton
OPERA detectorSM1 SM2
VETOTarget area Magnet and RPCs
PT Brick Manipulator System
Extract and validate the ECC brickDevelop and send to scanning labs
Parallel analysis of ECC bricksbull Validated bricks are sent to the scanning labs
ndash 10 scanning labs share the scanning
bull Swiss scanning station scanned the highest number of bricks in Europe for 2008 run
To Japan
Padova
To MosccowLHEP
GS
Scanning labs Nagoya (JP)LHEP Bern (CH)Napoli Bari Salerno Bologna Padova Roma Frascati (IT)Dubna (Ru)
Swiss scanning station in LHEP Bern
bull Largest scanning group in Europendash 10 physicists (Bern + ETHZ)ndash 5 microscopes with full-automatic plate changerndash Capability to scan more than 15 bricksweek
0
2E+18
4E+18
6E+18
8E+18
1E+19
12E+19
14E+19
16E+19
18E+19
18-J
un
28-J
un
8-Ju
l
18-J
ul
28-J
ul
7-A
ug
17-A
ug
27-A
ug
6-S
ep
16-S
ep
26-S
ep
6-O
ct
16-O
ct
26-O
ct
5-N
ov
inte
gra
ted
po
t
Total 1781019 pot
18kV cable repair
MD
PS magnet exchange septum bakeout
MD
SPS timing faultvacuum leak amp magnet exchange
CNGS maintenance
SPS extraction line Magnet ground fault MD
CNGS maintenance
Nominal 45 1019 potyr for 5 years
Beam to CNGSLHC FT MD
Beam to CNGSLHC FT
Beam to CNGS MD
2008 CNGS run (18 June - 03 Nov 2008) first physics run
Located neutrino interactions
Brick 81813
Brick 24487
Emulsion gives 3D vector data In ECC brick we can reconstruct vertices with an accuracy of a few micron(The frames correspond to emulsion films The other colored line shows the extrapolation of measured tracks The color indicates the Z-depth in the module)
1 cm
Brick 82372
(animation)
Status of event location in ECC for 2008 run
Scanning for 2008 run will be completed by September 2009
with muon without muon Total
Events in target 1663
Bricks developped 959 218 1177
Vertices located in ECC 678 119 797
Vertices in the dead material 17 4 21
Impact parameter distribution
mm
Analysis for located eventsbull Goal of 2008 run
ndash Check nu-tau detection efficiency by detecting charmed particles (similar life time and mass with tau)
bull Charm particles are produced in nu-mu CC interactionsbull ~23 events are expected for ~1200 nu-mu CC events
ndash Nu-tau detectionbull 07 event is expectedbull No clear candidate up to now
Particle Mass (MeVc2) Life time (10-15 s) cτ (micron)
τ 17769 291 871
D+ 18693 1040 3118
Ds+ 19682 500 1499
Λc+ 22865 200 599
Charm candidate 51284 (di-muon event)
kink
x-view
1ryvertex 4 mm
13 mm
flight length 1330 micronkink angle 209 mradIP of daughter 262 microndaughter muon 22 GeVcdecay Pt 046 GeVc
1ry muon
daughter muon
(animation)
Charm candidate 72853
Both 1ry vertex and decay point are in lead plate
muon
Lead plate
1ryvertex
IP wrt muon(micron)
IP wrt decay point(micron)
Momentum(GeVc)
Daughter1 370 05 13
Daughter2 135 04 23
342 micron
muon
(animation)
muon
muon
Lead plate (1 mm)
Hypothesis (1) D0 candidate
Hypothesis (2) t candidate
minimum kink angle 312 mradmuon momentum 17 GeVcPt gt 53 GeVc
Excluded by Pt Pt gt maximum decay Pt of t (09 GeVc)
1ryvertex
1ryvertex
D0
t
Charm candidates
Expected ratio Number of candidates
1-prong 37 5
2-prong 30 4
3-prong 19 1
4-prong 7 1
Analysis ongoing for located ~700 nu-mu CC eventsUp to now we have collected 11 candidates
13 events are expected for 700 nu-mu CC events(23 events are expected for 1200 nu-mu CC events)
Activities of Swiss group in OPERA analysis
bull Common for all labsndash Decay searchndash Kinematical analysis
bull Unique to Swiss groupndash Study of hadronic background for taundash Gamma detection energy estimation π0 reconstructionndash MC studies on tau and charmndash Electron ID energy estimationndash Low momentum muon IDndash Development of 3D display for event analysis
Study of hadronic background for tau
bull Motivationndash Hadronic re-interaction is a major source of background for hadronic decay
channel of tau Monte Carlo has large uncertainties (MC says a hadron track of 1mm length creates a decay-like topology with a probability of 10-5)
bull Methodndash Analyze the particles from neutrino interaction vertices Measure the number
of decay-like interactions and study Pt distribution etc
tau hadron1ryvertex
non-mu non-mu
Hadronic re-interaction background from nm NC interaction
nt CC interaction
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
CNGS beam
lt E gt 17 GeV
L 730 km
( e + e) 087
4
prompt negligible
Expected interactions in 5 years ~25400 CC + NC
~170 e + e CC~125 CC (m2 = 25 x 10-3 eV2)
L = 732 kmCERNLNGS
Tflight = 244 ms
CERN
LNGS
730 km
~10 tau decays are expectedto be observed
after 5 years running
102 cm
125 cm75 cm
neutrino
OPERA target
ECC brick
OPERA Brick = 57 nuclear emulsion films interleaved by 1 mm thick lead plates
OPERA Film = 2 emulsion layers (44 m thick)
poured on a 205 m plastic base
OPERA Film times 57 plates
Lead x 56 plates
OPERA Film
Lead plate
1mm03mm
The OPERA target consists of
about 150000 bricks
Total target mass 125 kton
OPERA detectorSM1 SM2
VETOTarget area Magnet and RPCs
PT Brick Manipulator System
Extract and validate the ECC brickDevelop and send to scanning labs
Parallel analysis of ECC bricksbull Validated bricks are sent to the scanning labs
ndash 10 scanning labs share the scanning
bull Swiss scanning station scanned the highest number of bricks in Europe for 2008 run
To Japan
Padova
To MosccowLHEP
GS
Scanning labs Nagoya (JP)LHEP Bern (CH)Napoli Bari Salerno Bologna Padova Roma Frascati (IT)Dubna (Ru)
Swiss scanning station in LHEP Bern
bull Largest scanning group in Europendash 10 physicists (Bern + ETHZ)ndash 5 microscopes with full-automatic plate changerndash Capability to scan more than 15 bricksweek
0
2E+18
4E+18
6E+18
8E+18
1E+19
12E+19
14E+19
16E+19
18E+19
18-J
un
28-J
un
8-Ju
l
18-J
ul
28-J
ul
7-A
ug
17-A
ug
27-A
ug
6-S
ep
16-S
ep
26-S
ep
6-O
ct
16-O
ct
26-O
ct
5-N
ov
inte
gra
ted
po
t
Total 1781019 pot
18kV cable repair
MD
PS magnet exchange septum bakeout
MD
SPS timing faultvacuum leak amp magnet exchange
CNGS maintenance
SPS extraction line Magnet ground fault MD
CNGS maintenance
Nominal 45 1019 potyr for 5 years
Beam to CNGSLHC FT MD
Beam to CNGSLHC FT
Beam to CNGS MD
2008 CNGS run (18 June - 03 Nov 2008) first physics run
Located neutrino interactions
Brick 81813
Brick 24487
Emulsion gives 3D vector data In ECC brick we can reconstruct vertices with an accuracy of a few micron(The frames correspond to emulsion films The other colored line shows the extrapolation of measured tracks The color indicates the Z-depth in the module)
1 cm
Brick 82372
(animation)
Status of event location in ECC for 2008 run
Scanning for 2008 run will be completed by September 2009
with muon without muon Total
Events in target 1663
Bricks developped 959 218 1177
Vertices located in ECC 678 119 797
Vertices in the dead material 17 4 21
Impact parameter distribution
mm
Analysis for located eventsbull Goal of 2008 run
ndash Check nu-tau detection efficiency by detecting charmed particles (similar life time and mass with tau)
bull Charm particles are produced in nu-mu CC interactionsbull ~23 events are expected for ~1200 nu-mu CC events
ndash Nu-tau detectionbull 07 event is expectedbull No clear candidate up to now
Particle Mass (MeVc2) Life time (10-15 s) cτ (micron)
τ 17769 291 871
D+ 18693 1040 3118
Ds+ 19682 500 1499
Λc+ 22865 200 599
Charm candidate 51284 (di-muon event)
kink
x-view
1ryvertex 4 mm
13 mm
flight length 1330 micronkink angle 209 mradIP of daughter 262 microndaughter muon 22 GeVcdecay Pt 046 GeVc
1ry muon
daughter muon
(animation)
Charm candidate 72853
Both 1ry vertex and decay point are in lead plate
muon
Lead plate
1ryvertex
IP wrt muon(micron)
IP wrt decay point(micron)
Momentum(GeVc)
Daughter1 370 05 13
Daughter2 135 04 23
342 micron
muon
(animation)
muon
muon
Lead plate (1 mm)
Hypothesis (1) D0 candidate
Hypothesis (2) t candidate
minimum kink angle 312 mradmuon momentum 17 GeVcPt gt 53 GeVc
Excluded by Pt Pt gt maximum decay Pt of t (09 GeVc)
1ryvertex
1ryvertex
D0
t
Charm candidates
Expected ratio Number of candidates
1-prong 37 5
2-prong 30 4
3-prong 19 1
4-prong 7 1
Analysis ongoing for located ~700 nu-mu CC eventsUp to now we have collected 11 candidates
13 events are expected for 700 nu-mu CC events(23 events are expected for 1200 nu-mu CC events)
Activities of Swiss group in OPERA analysis
bull Common for all labsndash Decay searchndash Kinematical analysis
bull Unique to Swiss groupndash Study of hadronic background for taundash Gamma detection energy estimation π0 reconstructionndash MC studies on tau and charmndash Electron ID energy estimationndash Low momentum muon IDndash Development of 3D display for event analysis
Study of hadronic background for tau
bull Motivationndash Hadronic re-interaction is a major source of background for hadronic decay
channel of tau Monte Carlo has large uncertainties (MC says a hadron track of 1mm length creates a decay-like topology with a probability of 10-5)
bull Methodndash Analyze the particles from neutrino interaction vertices Measure the number
of decay-like interactions and study Pt distribution etc
tau hadron1ryvertex
non-mu non-mu
Hadronic re-interaction background from nm NC interaction
nt CC interaction
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
102 cm
125 cm75 cm
neutrino
OPERA target
ECC brick
OPERA Brick = 57 nuclear emulsion films interleaved by 1 mm thick lead plates
OPERA Film = 2 emulsion layers (44 m thick)
poured on a 205 m plastic base
OPERA Film times 57 plates
Lead x 56 plates
OPERA Film
Lead plate
1mm03mm
The OPERA target consists of
about 150000 bricks
Total target mass 125 kton
OPERA detectorSM1 SM2
VETOTarget area Magnet and RPCs
PT Brick Manipulator System
Extract and validate the ECC brickDevelop and send to scanning labs
Parallel analysis of ECC bricksbull Validated bricks are sent to the scanning labs
ndash 10 scanning labs share the scanning
bull Swiss scanning station scanned the highest number of bricks in Europe for 2008 run
To Japan
Padova
To MosccowLHEP
GS
Scanning labs Nagoya (JP)LHEP Bern (CH)Napoli Bari Salerno Bologna Padova Roma Frascati (IT)Dubna (Ru)
Swiss scanning station in LHEP Bern
bull Largest scanning group in Europendash 10 physicists (Bern + ETHZ)ndash 5 microscopes with full-automatic plate changerndash Capability to scan more than 15 bricksweek
0
2E+18
4E+18
6E+18
8E+18
1E+19
12E+19
14E+19
16E+19
18E+19
18-J
un
28-J
un
8-Ju
l
18-J
ul
28-J
ul
7-A
ug
17-A
ug
27-A
ug
6-S
ep
16-S
ep
26-S
ep
6-O
ct
16-O
ct
26-O
ct
5-N
ov
inte
gra
ted
po
t
Total 1781019 pot
18kV cable repair
MD
PS magnet exchange septum bakeout
MD
SPS timing faultvacuum leak amp magnet exchange
CNGS maintenance
SPS extraction line Magnet ground fault MD
CNGS maintenance
Nominal 45 1019 potyr for 5 years
Beam to CNGSLHC FT MD
Beam to CNGSLHC FT
Beam to CNGS MD
2008 CNGS run (18 June - 03 Nov 2008) first physics run
Located neutrino interactions
Brick 81813
Brick 24487
Emulsion gives 3D vector data In ECC brick we can reconstruct vertices with an accuracy of a few micron(The frames correspond to emulsion films The other colored line shows the extrapolation of measured tracks The color indicates the Z-depth in the module)
1 cm
Brick 82372
(animation)
Status of event location in ECC for 2008 run
Scanning for 2008 run will be completed by September 2009
with muon without muon Total
Events in target 1663
Bricks developped 959 218 1177
Vertices located in ECC 678 119 797
Vertices in the dead material 17 4 21
Impact parameter distribution
mm
Analysis for located eventsbull Goal of 2008 run
ndash Check nu-tau detection efficiency by detecting charmed particles (similar life time and mass with tau)
bull Charm particles are produced in nu-mu CC interactionsbull ~23 events are expected for ~1200 nu-mu CC events
ndash Nu-tau detectionbull 07 event is expectedbull No clear candidate up to now
Particle Mass (MeVc2) Life time (10-15 s) cτ (micron)
τ 17769 291 871
D+ 18693 1040 3118
Ds+ 19682 500 1499
Λc+ 22865 200 599
Charm candidate 51284 (di-muon event)
kink
x-view
1ryvertex 4 mm
13 mm
flight length 1330 micronkink angle 209 mradIP of daughter 262 microndaughter muon 22 GeVcdecay Pt 046 GeVc
1ry muon
daughter muon
(animation)
Charm candidate 72853
Both 1ry vertex and decay point are in lead plate
muon
Lead plate
1ryvertex
IP wrt muon(micron)
IP wrt decay point(micron)
Momentum(GeVc)
Daughter1 370 05 13
Daughter2 135 04 23
342 micron
muon
(animation)
muon
muon
Lead plate (1 mm)
Hypothesis (1) D0 candidate
Hypothesis (2) t candidate
minimum kink angle 312 mradmuon momentum 17 GeVcPt gt 53 GeVc
Excluded by Pt Pt gt maximum decay Pt of t (09 GeVc)
1ryvertex
1ryvertex
D0
t
Charm candidates
Expected ratio Number of candidates
1-prong 37 5
2-prong 30 4
3-prong 19 1
4-prong 7 1
Analysis ongoing for located ~700 nu-mu CC eventsUp to now we have collected 11 candidates
13 events are expected for 700 nu-mu CC events(23 events are expected for 1200 nu-mu CC events)
Activities of Swiss group in OPERA analysis
bull Common for all labsndash Decay searchndash Kinematical analysis
bull Unique to Swiss groupndash Study of hadronic background for taundash Gamma detection energy estimation π0 reconstructionndash MC studies on tau and charmndash Electron ID energy estimationndash Low momentum muon IDndash Development of 3D display for event analysis
Study of hadronic background for tau
bull Motivationndash Hadronic re-interaction is a major source of background for hadronic decay
channel of tau Monte Carlo has large uncertainties (MC says a hadron track of 1mm length creates a decay-like topology with a probability of 10-5)
bull Methodndash Analyze the particles from neutrino interaction vertices Measure the number
of decay-like interactions and study Pt distribution etc
tau hadron1ryvertex
non-mu non-mu
Hadronic re-interaction background from nm NC interaction
nt CC interaction
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
OPERA detectorSM1 SM2
VETOTarget area Magnet and RPCs
PT Brick Manipulator System
Extract and validate the ECC brickDevelop and send to scanning labs
Parallel analysis of ECC bricksbull Validated bricks are sent to the scanning labs
ndash 10 scanning labs share the scanning
bull Swiss scanning station scanned the highest number of bricks in Europe for 2008 run
To Japan
Padova
To MosccowLHEP
GS
Scanning labs Nagoya (JP)LHEP Bern (CH)Napoli Bari Salerno Bologna Padova Roma Frascati (IT)Dubna (Ru)
Swiss scanning station in LHEP Bern
bull Largest scanning group in Europendash 10 physicists (Bern + ETHZ)ndash 5 microscopes with full-automatic plate changerndash Capability to scan more than 15 bricksweek
0
2E+18
4E+18
6E+18
8E+18
1E+19
12E+19
14E+19
16E+19
18E+19
18-J
un
28-J
un
8-Ju
l
18-J
ul
28-J
ul
7-A
ug
17-A
ug
27-A
ug
6-S
ep
16-S
ep
26-S
ep
6-O
ct
16-O
ct
26-O
ct
5-N
ov
inte
gra
ted
po
t
Total 1781019 pot
18kV cable repair
MD
PS magnet exchange septum bakeout
MD
SPS timing faultvacuum leak amp magnet exchange
CNGS maintenance
SPS extraction line Magnet ground fault MD
CNGS maintenance
Nominal 45 1019 potyr for 5 years
Beam to CNGSLHC FT MD
Beam to CNGSLHC FT
Beam to CNGS MD
2008 CNGS run (18 June - 03 Nov 2008) first physics run
Located neutrino interactions
Brick 81813
Brick 24487
Emulsion gives 3D vector data In ECC brick we can reconstruct vertices with an accuracy of a few micron(The frames correspond to emulsion films The other colored line shows the extrapolation of measured tracks The color indicates the Z-depth in the module)
1 cm
Brick 82372
(animation)
Status of event location in ECC for 2008 run
Scanning for 2008 run will be completed by September 2009
with muon without muon Total
Events in target 1663
Bricks developped 959 218 1177
Vertices located in ECC 678 119 797
Vertices in the dead material 17 4 21
Impact parameter distribution
mm
Analysis for located eventsbull Goal of 2008 run
ndash Check nu-tau detection efficiency by detecting charmed particles (similar life time and mass with tau)
bull Charm particles are produced in nu-mu CC interactionsbull ~23 events are expected for ~1200 nu-mu CC events
ndash Nu-tau detectionbull 07 event is expectedbull No clear candidate up to now
Particle Mass (MeVc2) Life time (10-15 s) cτ (micron)
τ 17769 291 871
D+ 18693 1040 3118
Ds+ 19682 500 1499
Λc+ 22865 200 599
Charm candidate 51284 (di-muon event)
kink
x-view
1ryvertex 4 mm
13 mm
flight length 1330 micronkink angle 209 mradIP of daughter 262 microndaughter muon 22 GeVcdecay Pt 046 GeVc
1ry muon
daughter muon
(animation)
Charm candidate 72853
Both 1ry vertex and decay point are in lead plate
muon
Lead plate
1ryvertex
IP wrt muon(micron)
IP wrt decay point(micron)
Momentum(GeVc)
Daughter1 370 05 13
Daughter2 135 04 23
342 micron
muon
(animation)
muon
muon
Lead plate (1 mm)
Hypothesis (1) D0 candidate
Hypothesis (2) t candidate
minimum kink angle 312 mradmuon momentum 17 GeVcPt gt 53 GeVc
Excluded by Pt Pt gt maximum decay Pt of t (09 GeVc)
1ryvertex
1ryvertex
D0
t
Charm candidates
Expected ratio Number of candidates
1-prong 37 5
2-prong 30 4
3-prong 19 1
4-prong 7 1
Analysis ongoing for located ~700 nu-mu CC eventsUp to now we have collected 11 candidates
13 events are expected for 700 nu-mu CC events(23 events are expected for 1200 nu-mu CC events)
Activities of Swiss group in OPERA analysis
bull Common for all labsndash Decay searchndash Kinematical analysis
bull Unique to Swiss groupndash Study of hadronic background for taundash Gamma detection energy estimation π0 reconstructionndash MC studies on tau and charmndash Electron ID energy estimationndash Low momentum muon IDndash Development of 3D display for event analysis
Study of hadronic background for tau
bull Motivationndash Hadronic re-interaction is a major source of background for hadronic decay
channel of tau Monte Carlo has large uncertainties (MC says a hadron track of 1mm length creates a decay-like topology with a probability of 10-5)
bull Methodndash Analyze the particles from neutrino interaction vertices Measure the number
of decay-like interactions and study Pt distribution etc
tau hadron1ryvertex
non-mu non-mu
Hadronic re-interaction background from nm NC interaction
nt CC interaction
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
Parallel analysis of ECC bricksbull Validated bricks are sent to the scanning labs
ndash 10 scanning labs share the scanning
bull Swiss scanning station scanned the highest number of bricks in Europe for 2008 run
To Japan
Padova
To MosccowLHEP
GS
Scanning labs Nagoya (JP)LHEP Bern (CH)Napoli Bari Salerno Bologna Padova Roma Frascati (IT)Dubna (Ru)
Swiss scanning station in LHEP Bern
bull Largest scanning group in Europendash 10 physicists (Bern + ETHZ)ndash 5 microscopes with full-automatic plate changerndash Capability to scan more than 15 bricksweek
0
2E+18
4E+18
6E+18
8E+18
1E+19
12E+19
14E+19
16E+19
18E+19
18-J
un
28-J
un
8-Ju
l
18-J
ul
28-J
ul
7-A
ug
17-A
ug
27-A
ug
6-S
ep
16-S
ep
26-S
ep
6-O
ct
16-O
ct
26-O
ct
5-N
ov
inte
gra
ted
po
t
Total 1781019 pot
18kV cable repair
MD
PS magnet exchange septum bakeout
MD
SPS timing faultvacuum leak amp magnet exchange
CNGS maintenance
SPS extraction line Magnet ground fault MD
CNGS maintenance
Nominal 45 1019 potyr for 5 years
Beam to CNGSLHC FT MD
Beam to CNGSLHC FT
Beam to CNGS MD
2008 CNGS run (18 June - 03 Nov 2008) first physics run
Located neutrino interactions
Brick 81813
Brick 24487
Emulsion gives 3D vector data In ECC brick we can reconstruct vertices with an accuracy of a few micron(The frames correspond to emulsion films The other colored line shows the extrapolation of measured tracks The color indicates the Z-depth in the module)
1 cm
Brick 82372
(animation)
Status of event location in ECC for 2008 run
Scanning for 2008 run will be completed by September 2009
with muon without muon Total
Events in target 1663
Bricks developped 959 218 1177
Vertices located in ECC 678 119 797
Vertices in the dead material 17 4 21
Impact parameter distribution
mm
Analysis for located eventsbull Goal of 2008 run
ndash Check nu-tau detection efficiency by detecting charmed particles (similar life time and mass with tau)
bull Charm particles are produced in nu-mu CC interactionsbull ~23 events are expected for ~1200 nu-mu CC events
ndash Nu-tau detectionbull 07 event is expectedbull No clear candidate up to now
Particle Mass (MeVc2) Life time (10-15 s) cτ (micron)
τ 17769 291 871
D+ 18693 1040 3118
Ds+ 19682 500 1499
Λc+ 22865 200 599
Charm candidate 51284 (di-muon event)
kink
x-view
1ryvertex 4 mm
13 mm
flight length 1330 micronkink angle 209 mradIP of daughter 262 microndaughter muon 22 GeVcdecay Pt 046 GeVc
1ry muon
daughter muon
(animation)
Charm candidate 72853
Both 1ry vertex and decay point are in lead plate
muon
Lead plate
1ryvertex
IP wrt muon(micron)
IP wrt decay point(micron)
Momentum(GeVc)
Daughter1 370 05 13
Daughter2 135 04 23
342 micron
muon
(animation)
muon
muon
Lead plate (1 mm)
Hypothesis (1) D0 candidate
Hypothesis (2) t candidate
minimum kink angle 312 mradmuon momentum 17 GeVcPt gt 53 GeVc
Excluded by Pt Pt gt maximum decay Pt of t (09 GeVc)
1ryvertex
1ryvertex
D0
t
Charm candidates
Expected ratio Number of candidates
1-prong 37 5
2-prong 30 4
3-prong 19 1
4-prong 7 1
Analysis ongoing for located ~700 nu-mu CC eventsUp to now we have collected 11 candidates
13 events are expected for 700 nu-mu CC events(23 events are expected for 1200 nu-mu CC events)
Activities of Swiss group in OPERA analysis
bull Common for all labsndash Decay searchndash Kinematical analysis
bull Unique to Swiss groupndash Study of hadronic background for taundash Gamma detection energy estimation π0 reconstructionndash MC studies on tau and charmndash Electron ID energy estimationndash Low momentum muon IDndash Development of 3D display for event analysis
Study of hadronic background for tau
bull Motivationndash Hadronic re-interaction is a major source of background for hadronic decay
channel of tau Monte Carlo has large uncertainties (MC says a hadron track of 1mm length creates a decay-like topology with a probability of 10-5)
bull Methodndash Analyze the particles from neutrino interaction vertices Measure the number
of decay-like interactions and study Pt distribution etc
tau hadron1ryvertex
non-mu non-mu
Hadronic re-interaction background from nm NC interaction
nt CC interaction
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
Swiss scanning station in LHEP Bern
bull Largest scanning group in Europendash 10 physicists (Bern + ETHZ)ndash 5 microscopes with full-automatic plate changerndash Capability to scan more than 15 bricksweek
0
2E+18
4E+18
6E+18
8E+18
1E+19
12E+19
14E+19
16E+19
18E+19
18-J
un
28-J
un
8-Ju
l
18-J
ul
28-J
ul
7-A
ug
17-A
ug
27-A
ug
6-S
ep
16-S
ep
26-S
ep
6-O
ct
16-O
ct
26-O
ct
5-N
ov
inte
gra
ted
po
t
Total 1781019 pot
18kV cable repair
MD
PS magnet exchange septum bakeout
MD
SPS timing faultvacuum leak amp magnet exchange
CNGS maintenance
SPS extraction line Magnet ground fault MD
CNGS maintenance
Nominal 45 1019 potyr for 5 years
Beam to CNGSLHC FT MD
Beam to CNGSLHC FT
Beam to CNGS MD
2008 CNGS run (18 June - 03 Nov 2008) first physics run
Located neutrino interactions
Brick 81813
Brick 24487
Emulsion gives 3D vector data In ECC brick we can reconstruct vertices with an accuracy of a few micron(The frames correspond to emulsion films The other colored line shows the extrapolation of measured tracks The color indicates the Z-depth in the module)
1 cm
Brick 82372
(animation)
Status of event location in ECC for 2008 run
Scanning for 2008 run will be completed by September 2009
with muon without muon Total
Events in target 1663
Bricks developped 959 218 1177
Vertices located in ECC 678 119 797
Vertices in the dead material 17 4 21
Impact parameter distribution
mm
Analysis for located eventsbull Goal of 2008 run
ndash Check nu-tau detection efficiency by detecting charmed particles (similar life time and mass with tau)
bull Charm particles are produced in nu-mu CC interactionsbull ~23 events are expected for ~1200 nu-mu CC events
ndash Nu-tau detectionbull 07 event is expectedbull No clear candidate up to now
Particle Mass (MeVc2) Life time (10-15 s) cτ (micron)
τ 17769 291 871
D+ 18693 1040 3118
Ds+ 19682 500 1499
Λc+ 22865 200 599
Charm candidate 51284 (di-muon event)
kink
x-view
1ryvertex 4 mm
13 mm
flight length 1330 micronkink angle 209 mradIP of daughter 262 microndaughter muon 22 GeVcdecay Pt 046 GeVc
1ry muon
daughter muon
(animation)
Charm candidate 72853
Both 1ry vertex and decay point are in lead plate
muon
Lead plate
1ryvertex
IP wrt muon(micron)
IP wrt decay point(micron)
Momentum(GeVc)
Daughter1 370 05 13
Daughter2 135 04 23
342 micron
muon
(animation)
muon
muon
Lead plate (1 mm)
Hypothesis (1) D0 candidate
Hypothesis (2) t candidate
minimum kink angle 312 mradmuon momentum 17 GeVcPt gt 53 GeVc
Excluded by Pt Pt gt maximum decay Pt of t (09 GeVc)
1ryvertex
1ryvertex
D0
t
Charm candidates
Expected ratio Number of candidates
1-prong 37 5
2-prong 30 4
3-prong 19 1
4-prong 7 1
Analysis ongoing for located ~700 nu-mu CC eventsUp to now we have collected 11 candidates
13 events are expected for 700 nu-mu CC events(23 events are expected for 1200 nu-mu CC events)
Activities of Swiss group in OPERA analysis
bull Common for all labsndash Decay searchndash Kinematical analysis
bull Unique to Swiss groupndash Study of hadronic background for taundash Gamma detection energy estimation π0 reconstructionndash MC studies on tau and charmndash Electron ID energy estimationndash Low momentum muon IDndash Development of 3D display for event analysis
Study of hadronic background for tau
bull Motivationndash Hadronic re-interaction is a major source of background for hadronic decay
channel of tau Monte Carlo has large uncertainties (MC says a hadron track of 1mm length creates a decay-like topology with a probability of 10-5)
bull Methodndash Analyze the particles from neutrino interaction vertices Measure the number
of decay-like interactions and study Pt distribution etc
tau hadron1ryvertex
non-mu non-mu
Hadronic re-interaction background from nm NC interaction
nt CC interaction
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
0
2E+18
4E+18
6E+18
8E+18
1E+19
12E+19
14E+19
16E+19
18E+19
18-J
un
28-J
un
8-Ju
l
18-J
ul
28-J
ul
7-A
ug
17-A
ug
27-A
ug
6-S
ep
16-S
ep
26-S
ep
6-O
ct
16-O
ct
26-O
ct
5-N
ov
inte
gra
ted
po
t
Total 1781019 pot
18kV cable repair
MD
PS magnet exchange septum bakeout
MD
SPS timing faultvacuum leak amp magnet exchange
CNGS maintenance
SPS extraction line Magnet ground fault MD
CNGS maintenance
Nominal 45 1019 potyr for 5 years
Beam to CNGSLHC FT MD
Beam to CNGSLHC FT
Beam to CNGS MD
2008 CNGS run (18 June - 03 Nov 2008) first physics run
Located neutrino interactions
Brick 81813
Brick 24487
Emulsion gives 3D vector data In ECC brick we can reconstruct vertices with an accuracy of a few micron(The frames correspond to emulsion films The other colored line shows the extrapolation of measured tracks The color indicates the Z-depth in the module)
1 cm
Brick 82372
(animation)
Status of event location in ECC for 2008 run
Scanning for 2008 run will be completed by September 2009
with muon without muon Total
Events in target 1663
Bricks developped 959 218 1177
Vertices located in ECC 678 119 797
Vertices in the dead material 17 4 21
Impact parameter distribution
mm
Analysis for located eventsbull Goal of 2008 run
ndash Check nu-tau detection efficiency by detecting charmed particles (similar life time and mass with tau)
bull Charm particles are produced in nu-mu CC interactionsbull ~23 events are expected for ~1200 nu-mu CC events
ndash Nu-tau detectionbull 07 event is expectedbull No clear candidate up to now
Particle Mass (MeVc2) Life time (10-15 s) cτ (micron)
τ 17769 291 871
D+ 18693 1040 3118
Ds+ 19682 500 1499
Λc+ 22865 200 599
Charm candidate 51284 (di-muon event)
kink
x-view
1ryvertex 4 mm
13 mm
flight length 1330 micronkink angle 209 mradIP of daughter 262 microndaughter muon 22 GeVcdecay Pt 046 GeVc
1ry muon
daughter muon
(animation)
Charm candidate 72853
Both 1ry vertex and decay point are in lead plate
muon
Lead plate
1ryvertex
IP wrt muon(micron)
IP wrt decay point(micron)
Momentum(GeVc)
Daughter1 370 05 13
Daughter2 135 04 23
342 micron
muon
(animation)
muon
muon
Lead plate (1 mm)
Hypothesis (1) D0 candidate
Hypothesis (2) t candidate
minimum kink angle 312 mradmuon momentum 17 GeVcPt gt 53 GeVc
Excluded by Pt Pt gt maximum decay Pt of t (09 GeVc)
1ryvertex
1ryvertex
D0
t
Charm candidates
Expected ratio Number of candidates
1-prong 37 5
2-prong 30 4
3-prong 19 1
4-prong 7 1
Analysis ongoing for located ~700 nu-mu CC eventsUp to now we have collected 11 candidates
13 events are expected for 700 nu-mu CC events(23 events are expected for 1200 nu-mu CC events)
Activities of Swiss group in OPERA analysis
bull Common for all labsndash Decay searchndash Kinematical analysis
bull Unique to Swiss groupndash Study of hadronic background for taundash Gamma detection energy estimation π0 reconstructionndash MC studies on tau and charmndash Electron ID energy estimationndash Low momentum muon IDndash Development of 3D display for event analysis
Study of hadronic background for tau
bull Motivationndash Hadronic re-interaction is a major source of background for hadronic decay
channel of tau Monte Carlo has large uncertainties (MC says a hadron track of 1mm length creates a decay-like topology with a probability of 10-5)
bull Methodndash Analyze the particles from neutrino interaction vertices Measure the number
of decay-like interactions and study Pt distribution etc
tau hadron1ryvertex
non-mu non-mu
Hadronic re-interaction background from nm NC interaction
nt CC interaction
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
Located neutrino interactions
Brick 81813
Brick 24487
Emulsion gives 3D vector data In ECC brick we can reconstruct vertices with an accuracy of a few micron(The frames correspond to emulsion films The other colored line shows the extrapolation of measured tracks The color indicates the Z-depth in the module)
1 cm
Brick 82372
(animation)
Status of event location in ECC for 2008 run
Scanning for 2008 run will be completed by September 2009
with muon without muon Total
Events in target 1663
Bricks developped 959 218 1177
Vertices located in ECC 678 119 797
Vertices in the dead material 17 4 21
Impact parameter distribution
mm
Analysis for located eventsbull Goal of 2008 run
ndash Check nu-tau detection efficiency by detecting charmed particles (similar life time and mass with tau)
bull Charm particles are produced in nu-mu CC interactionsbull ~23 events are expected for ~1200 nu-mu CC events
ndash Nu-tau detectionbull 07 event is expectedbull No clear candidate up to now
Particle Mass (MeVc2) Life time (10-15 s) cτ (micron)
τ 17769 291 871
D+ 18693 1040 3118
Ds+ 19682 500 1499
Λc+ 22865 200 599
Charm candidate 51284 (di-muon event)
kink
x-view
1ryvertex 4 mm
13 mm
flight length 1330 micronkink angle 209 mradIP of daughter 262 microndaughter muon 22 GeVcdecay Pt 046 GeVc
1ry muon
daughter muon
(animation)
Charm candidate 72853
Both 1ry vertex and decay point are in lead plate
muon
Lead plate
1ryvertex
IP wrt muon(micron)
IP wrt decay point(micron)
Momentum(GeVc)
Daughter1 370 05 13
Daughter2 135 04 23
342 micron
muon
(animation)
muon
muon
Lead plate (1 mm)
Hypothesis (1) D0 candidate
Hypothesis (2) t candidate
minimum kink angle 312 mradmuon momentum 17 GeVcPt gt 53 GeVc
Excluded by Pt Pt gt maximum decay Pt of t (09 GeVc)
1ryvertex
1ryvertex
D0
t
Charm candidates
Expected ratio Number of candidates
1-prong 37 5
2-prong 30 4
3-prong 19 1
4-prong 7 1
Analysis ongoing for located ~700 nu-mu CC eventsUp to now we have collected 11 candidates
13 events are expected for 700 nu-mu CC events(23 events are expected for 1200 nu-mu CC events)
Activities of Swiss group in OPERA analysis
bull Common for all labsndash Decay searchndash Kinematical analysis
bull Unique to Swiss groupndash Study of hadronic background for taundash Gamma detection energy estimation π0 reconstructionndash MC studies on tau and charmndash Electron ID energy estimationndash Low momentum muon IDndash Development of 3D display for event analysis
Study of hadronic background for tau
bull Motivationndash Hadronic re-interaction is a major source of background for hadronic decay
channel of tau Monte Carlo has large uncertainties (MC says a hadron track of 1mm length creates a decay-like topology with a probability of 10-5)
bull Methodndash Analyze the particles from neutrino interaction vertices Measure the number
of decay-like interactions and study Pt distribution etc
tau hadron1ryvertex
non-mu non-mu
Hadronic re-interaction background from nm NC interaction
nt CC interaction
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
Status of event location in ECC for 2008 run
Scanning for 2008 run will be completed by September 2009
with muon without muon Total
Events in target 1663
Bricks developped 959 218 1177
Vertices located in ECC 678 119 797
Vertices in the dead material 17 4 21
Impact parameter distribution
mm
Analysis for located eventsbull Goal of 2008 run
ndash Check nu-tau detection efficiency by detecting charmed particles (similar life time and mass with tau)
bull Charm particles are produced in nu-mu CC interactionsbull ~23 events are expected for ~1200 nu-mu CC events
ndash Nu-tau detectionbull 07 event is expectedbull No clear candidate up to now
Particle Mass (MeVc2) Life time (10-15 s) cτ (micron)
τ 17769 291 871
D+ 18693 1040 3118
Ds+ 19682 500 1499
Λc+ 22865 200 599
Charm candidate 51284 (di-muon event)
kink
x-view
1ryvertex 4 mm
13 mm
flight length 1330 micronkink angle 209 mradIP of daughter 262 microndaughter muon 22 GeVcdecay Pt 046 GeVc
1ry muon
daughter muon
(animation)
Charm candidate 72853
Both 1ry vertex and decay point are in lead plate
muon
Lead plate
1ryvertex
IP wrt muon(micron)
IP wrt decay point(micron)
Momentum(GeVc)
Daughter1 370 05 13
Daughter2 135 04 23
342 micron
muon
(animation)
muon
muon
Lead plate (1 mm)
Hypothesis (1) D0 candidate
Hypothesis (2) t candidate
minimum kink angle 312 mradmuon momentum 17 GeVcPt gt 53 GeVc
Excluded by Pt Pt gt maximum decay Pt of t (09 GeVc)
1ryvertex
1ryvertex
D0
t
Charm candidates
Expected ratio Number of candidates
1-prong 37 5
2-prong 30 4
3-prong 19 1
4-prong 7 1
Analysis ongoing for located ~700 nu-mu CC eventsUp to now we have collected 11 candidates
13 events are expected for 700 nu-mu CC events(23 events are expected for 1200 nu-mu CC events)
Activities of Swiss group in OPERA analysis
bull Common for all labsndash Decay searchndash Kinematical analysis
bull Unique to Swiss groupndash Study of hadronic background for taundash Gamma detection energy estimation π0 reconstructionndash MC studies on tau and charmndash Electron ID energy estimationndash Low momentum muon IDndash Development of 3D display for event analysis
Study of hadronic background for tau
bull Motivationndash Hadronic re-interaction is a major source of background for hadronic decay
channel of tau Monte Carlo has large uncertainties (MC says a hadron track of 1mm length creates a decay-like topology with a probability of 10-5)
bull Methodndash Analyze the particles from neutrino interaction vertices Measure the number
of decay-like interactions and study Pt distribution etc
tau hadron1ryvertex
non-mu non-mu
Hadronic re-interaction background from nm NC interaction
nt CC interaction
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
Analysis for located eventsbull Goal of 2008 run
ndash Check nu-tau detection efficiency by detecting charmed particles (similar life time and mass with tau)
bull Charm particles are produced in nu-mu CC interactionsbull ~23 events are expected for ~1200 nu-mu CC events
ndash Nu-tau detectionbull 07 event is expectedbull No clear candidate up to now
Particle Mass (MeVc2) Life time (10-15 s) cτ (micron)
τ 17769 291 871
D+ 18693 1040 3118
Ds+ 19682 500 1499
Λc+ 22865 200 599
Charm candidate 51284 (di-muon event)
kink
x-view
1ryvertex 4 mm
13 mm
flight length 1330 micronkink angle 209 mradIP of daughter 262 microndaughter muon 22 GeVcdecay Pt 046 GeVc
1ry muon
daughter muon
(animation)
Charm candidate 72853
Both 1ry vertex and decay point are in lead plate
muon
Lead plate
1ryvertex
IP wrt muon(micron)
IP wrt decay point(micron)
Momentum(GeVc)
Daughter1 370 05 13
Daughter2 135 04 23
342 micron
muon
(animation)
muon
muon
Lead plate (1 mm)
Hypothesis (1) D0 candidate
Hypothesis (2) t candidate
minimum kink angle 312 mradmuon momentum 17 GeVcPt gt 53 GeVc
Excluded by Pt Pt gt maximum decay Pt of t (09 GeVc)
1ryvertex
1ryvertex
D0
t
Charm candidates
Expected ratio Number of candidates
1-prong 37 5
2-prong 30 4
3-prong 19 1
4-prong 7 1
Analysis ongoing for located ~700 nu-mu CC eventsUp to now we have collected 11 candidates
13 events are expected for 700 nu-mu CC events(23 events are expected for 1200 nu-mu CC events)
Activities of Swiss group in OPERA analysis
bull Common for all labsndash Decay searchndash Kinematical analysis
bull Unique to Swiss groupndash Study of hadronic background for taundash Gamma detection energy estimation π0 reconstructionndash MC studies on tau and charmndash Electron ID energy estimationndash Low momentum muon IDndash Development of 3D display for event analysis
Study of hadronic background for tau
bull Motivationndash Hadronic re-interaction is a major source of background for hadronic decay
channel of tau Monte Carlo has large uncertainties (MC says a hadron track of 1mm length creates a decay-like topology with a probability of 10-5)
bull Methodndash Analyze the particles from neutrino interaction vertices Measure the number
of decay-like interactions and study Pt distribution etc
tau hadron1ryvertex
non-mu non-mu
Hadronic re-interaction background from nm NC interaction
nt CC interaction
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
Charm candidate 51284 (di-muon event)
kink
x-view
1ryvertex 4 mm
13 mm
flight length 1330 micronkink angle 209 mradIP of daughter 262 microndaughter muon 22 GeVcdecay Pt 046 GeVc
1ry muon
daughter muon
(animation)
Charm candidate 72853
Both 1ry vertex and decay point are in lead plate
muon
Lead plate
1ryvertex
IP wrt muon(micron)
IP wrt decay point(micron)
Momentum(GeVc)
Daughter1 370 05 13
Daughter2 135 04 23
342 micron
muon
(animation)
muon
muon
Lead plate (1 mm)
Hypothesis (1) D0 candidate
Hypothesis (2) t candidate
minimum kink angle 312 mradmuon momentum 17 GeVcPt gt 53 GeVc
Excluded by Pt Pt gt maximum decay Pt of t (09 GeVc)
1ryvertex
1ryvertex
D0
t
Charm candidates
Expected ratio Number of candidates
1-prong 37 5
2-prong 30 4
3-prong 19 1
4-prong 7 1
Analysis ongoing for located ~700 nu-mu CC eventsUp to now we have collected 11 candidates
13 events are expected for 700 nu-mu CC events(23 events are expected for 1200 nu-mu CC events)
Activities of Swiss group in OPERA analysis
bull Common for all labsndash Decay searchndash Kinematical analysis
bull Unique to Swiss groupndash Study of hadronic background for taundash Gamma detection energy estimation π0 reconstructionndash MC studies on tau and charmndash Electron ID energy estimationndash Low momentum muon IDndash Development of 3D display for event analysis
Study of hadronic background for tau
bull Motivationndash Hadronic re-interaction is a major source of background for hadronic decay
channel of tau Monte Carlo has large uncertainties (MC says a hadron track of 1mm length creates a decay-like topology with a probability of 10-5)
bull Methodndash Analyze the particles from neutrino interaction vertices Measure the number
of decay-like interactions and study Pt distribution etc
tau hadron1ryvertex
non-mu non-mu
Hadronic re-interaction background from nm NC interaction
nt CC interaction
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
Charm candidate 72853
Both 1ry vertex and decay point are in lead plate
muon
Lead plate
1ryvertex
IP wrt muon(micron)
IP wrt decay point(micron)
Momentum(GeVc)
Daughter1 370 05 13
Daughter2 135 04 23
342 micron
muon
(animation)
muon
muon
Lead plate (1 mm)
Hypothesis (1) D0 candidate
Hypothesis (2) t candidate
minimum kink angle 312 mradmuon momentum 17 GeVcPt gt 53 GeVc
Excluded by Pt Pt gt maximum decay Pt of t (09 GeVc)
1ryvertex
1ryvertex
D0
t
Charm candidates
Expected ratio Number of candidates
1-prong 37 5
2-prong 30 4
3-prong 19 1
4-prong 7 1
Analysis ongoing for located ~700 nu-mu CC eventsUp to now we have collected 11 candidates
13 events are expected for 700 nu-mu CC events(23 events are expected for 1200 nu-mu CC events)
Activities of Swiss group in OPERA analysis
bull Common for all labsndash Decay searchndash Kinematical analysis
bull Unique to Swiss groupndash Study of hadronic background for taundash Gamma detection energy estimation π0 reconstructionndash MC studies on tau and charmndash Electron ID energy estimationndash Low momentum muon IDndash Development of 3D display for event analysis
Study of hadronic background for tau
bull Motivationndash Hadronic re-interaction is a major source of background for hadronic decay
channel of tau Monte Carlo has large uncertainties (MC says a hadron track of 1mm length creates a decay-like topology with a probability of 10-5)
bull Methodndash Analyze the particles from neutrino interaction vertices Measure the number
of decay-like interactions and study Pt distribution etc
tau hadron1ryvertex
non-mu non-mu
Hadronic re-interaction background from nm NC interaction
nt CC interaction
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
muon
muon
Lead plate (1 mm)
Hypothesis (1) D0 candidate
Hypothesis (2) t candidate
minimum kink angle 312 mradmuon momentum 17 GeVcPt gt 53 GeVc
Excluded by Pt Pt gt maximum decay Pt of t (09 GeVc)
1ryvertex
1ryvertex
D0
t
Charm candidates
Expected ratio Number of candidates
1-prong 37 5
2-prong 30 4
3-prong 19 1
4-prong 7 1
Analysis ongoing for located ~700 nu-mu CC eventsUp to now we have collected 11 candidates
13 events are expected for 700 nu-mu CC events(23 events are expected for 1200 nu-mu CC events)
Activities of Swiss group in OPERA analysis
bull Common for all labsndash Decay searchndash Kinematical analysis
bull Unique to Swiss groupndash Study of hadronic background for taundash Gamma detection energy estimation π0 reconstructionndash MC studies on tau and charmndash Electron ID energy estimationndash Low momentum muon IDndash Development of 3D display for event analysis
Study of hadronic background for tau
bull Motivationndash Hadronic re-interaction is a major source of background for hadronic decay
channel of tau Monte Carlo has large uncertainties (MC says a hadron track of 1mm length creates a decay-like topology with a probability of 10-5)
bull Methodndash Analyze the particles from neutrino interaction vertices Measure the number
of decay-like interactions and study Pt distribution etc
tau hadron1ryvertex
non-mu non-mu
Hadronic re-interaction background from nm NC interaction
nt CC interaction
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
Charm candidates
Expected ratio Number of candidates
1-prong 37 5
2-prong 30 4
3-prong 19 1
4-prong 7 1
Analysis ongoing for located ~700 nu-mu CC eventsUp to now we have collected 11 candidates
13 events are expected for 700 nu-mu CC events(23 events are expected for 1200 nu-mu CC events)
Activities of Swiss group in OPERA analysis
bull Common for all labsndash Decay searchndash Kinematical analysis
bull Unique to Swiss groupndash Study of hadronic background for taundash Gamma detection energy estimation π0 reconstructionndash MC studies on tau and charmndash Electron ID energy estimationndash Low momentum muon IDndash Development of 3D display for event analysis
Study of hadronic background for tau
bull Motivationndash Hadronic re-interaction is a major source of background for hadronic decay
channel of tau Monte Carlo has large uncertainties (MC says a hadron track of 1mm length creates a decay-like topology with a probability of 10-5)
bull Methodndash Analyze the particles from neutrino interaction vertices Measure the number
of decay-like interactions and study Pt distribution etc
tau hadron1ryvertex
non-mu non-mu
Hadronic re-interaction background from nm NC interaction
nt CC interaction
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
Activities of Swiss group in OPERA analysis
bull Common for all labsndash Decay searchndash Kinematical analysis
bull Unique to Swiss groupndash Study of hadronic background for taundash Gamma detection energy estimation π0 reconstructionndash MC studies on tau and charmndash Electron ID energy estimationndash Low momentum muon IDndash Development of 3D display for event analysis
Study of hadronic background for tau
bull Motivationndash Hadronic re-interaction is a major source of background for hadronic decay
channel of tau Monte Carlo has large uncertainties (MC says a hadron track of 1mm length creates a decay-like topology with a probability of 10-5)
bull Methodndash Analyze the particles from neutrino interaction vertices Measure the number
of decay-like interactions and study Pt distribution etc
tau hadron1ryvertex
non-mu non-mu
Hadronic re-interaction background from nm NC interaction
nt CC interaction
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
Study of hadronic background for tau
bull Motivationndash Hadronic re-interaction is a major source of background for hadronic decay
channel of tau Monte Carlo has large uncertainties (MC says a hadron track of 1mm length creates a decay-like topology with a probability of 10-5)
bull Methodndash Analyze the particles from neutrino interaction vertices Measure the number
of decay-like interactions and study Pt distribution etc
tau hadron1ryvertex
non-mu non-mu
Hadronic re-interaction background from nm NC interaction
nt CC interaction
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
Study of hadronic background for tau
bull Status 48 m was scanned and studied by Swiss group 2ry vertices were found for 12 events Analysis is in progress
bull Goal ~30 m track length to measure background for the total decay search length for NC events collected in 5 years
1ry 2ry1ry 2ry
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
Gamma detection and π0 reconstruction
E ~05 GeV
E ~81 GeV
2 e-showers give a reconstructed mass ~ 160 MeVc2
70 of 1-prong tau hadronic decays include p0Important to detect gamma from tau decay to improve SN
We are working on gamma detection from nu-mu interactions to prove the methodπ0 reconstruction is in progress
g e-pair
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
Status and prospect for the on-going 2009 run
bull 154x1019 pot have been already collected up to Aug 17thbull 45x1019 pot are requested ~2 tau events are expected to be
detected
2006 0076x1019 pot 0 int Commissioning
2007 0082x1019 pot 38 int Commissioning
2008 178x1019 pot 1663 int First physics run
2009 154x1019 pot up to now (Aug 17th)
1629 int 32x1019 pot are expected at end of the run
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
Summarybull The OPERA experiment is taking data in the CNGS beambull 178x1019 pot were collected during the first physics run in
2008bull The analysis of 2008 data is in progressbull The evaluation of total efficiencies is ongoingbull In 2009 run 154x1019pot were already collected
ndash 45x1019 pot are requestedndash 32x1019 pot are expected at the end of the runndash Detection of ~2 nu-tau events is expectedhellipSOON
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
BACKUP
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
OPERA signal and background
decay channel
BR () Signal m2 = 25 x 10-3 eV2
Background
177 29 017
e 178 35 017
h 495 31 024
3h 150 09 017
Total 104 075
Full mixing 5 years run 45x1019 pot year
Main background sources bull Production and decay of charmed particles bull Hadron re-interactionsbull Large angle muon scattering
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
Pt estimation for charm candidate 72853
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
Tau background by D0
bull Neutral charmed particle decay vertex mistaken as primary vertex in events where only a muon and D0
are produced at primary vertex
channel
Cut on the invariant mass to be used to reduce this background source
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-
Pt cut
Daughter particle of τ
Daughter particle of hadronic re-interactions
Pt(GeVc) Pt(GeVc)
MC MC
- Status and results from OPERA
- OPERA
- CNGS beam
- Slide 4
- OPERA detector
- Parallel analysis of ECC bricks
- Swiss scanning station in LHEP Bern
- Slide 8
- Located neutrino interactions
- Status of event location in ECC for 2008 run
- Analysis for located events
- Slide 12
- Slide 13
- Slide 14
- Charm candidates
- Activities of Swiss group in OPERA analysis
- Study of hadronic background for tau
- Study of hadronic background for tau (2)
- Gamma detection and π0 reconstruction
- Status and prospect for the on-going 2009 run
- Summary
- Backup
- Slide 23
- Slide 24
- Slide 25
- Pt cut
-