a.k.ichikawa, kyoto university for the t2k...

θ13発見後のT2K実験

A.K.Ichikawa, Kyoto university

for the T2K collaboration

The T2K Collaboration

CanadaTRIUMFU. AlbertaU. B. ColumbiaU. ReginaU. TorontoU. VictoriaU. WinnipegYork U.

FranceCEA SaclayIPN LyonLLR E. Poly.LPNHE Paris

GermanyAachen U.

～500 members, 56 Institutes, 11 countriesItalyINFN, U. BariINFN, U. NapoliINFN, U. PadovaINFN, U. Roma

JapanICRR KamiokaICRR RCCNKEKKobe U.Kyoto U.Miyagi U. Edu.Osaka City U.U. Tokyo

PolandIFJ PAN, CracowNCBJ, WarsawU. Silesia, KatowiceU. WarsawWarsaw U. T.Wroklaw U.

RussiaINR

U. SheffieldU. Warwick

USABoston U.Colorado S. U.Duke U.Louisiana S. U.Stony Brook U.U. C. IrvineU. ColoradoU. PittsburghU. RochesterU. Washington

SpainIFAE, BarcelonaIFIC, Valencia

SwitzerlandETH ZurichU. BernU. Geneva

United KingdomImperial C. LondonLancaster U.Oxford U.Queen Mary U. L.STFC/DaresburySTFC/RALU. Liverpool

2

Tokai-to-Kamioka (T2K) experiment

e

Simulated event display

ELmP e /27.1sin2sinsin 231

213

223

2

ELmP x /27.1sin2sincos1 232

223

213

4

~0.6 GeV over 295km

信号

e appearance → 13

– e-like ring, 0 mass cut etc.

disappearance → 23

– -like ring etc.

Precise prediction based on measurement

p+C interaction by CERN NA61

ND280 measurement

-flux x x-sec

Data taking history

Jan2010

RUN1

RUN2

Great East Japan Earthquake (Mar. 11, 2011)

RUN3 RUN4

1.8% of T2K full stat.


Referred to > 550 times

6 events!!! over 1.5±0.3(sys) bkgs

Data taking history

Jan2010

RUN1

RUN2

Great East Japan Earthquake (Mar. 11, 2011)

RUN3 RUN4


e appearanceNormal Hierarchy case

Inverted Hierarchy case

Result w/ Run1-3 (11events) was released at ICHEP2012 in August: 3.2

Aiming to achieve ~5significance w/ data up to Summer 2013. (x2.6)

disappearance

9

best fitted spectrumnon oscill. spectrum

● Run 1-3 data

best fitted spectrum● Run 1-3 data

Recently updated w/ Run1-3 data (3.01x1020POT)

Update since July 2011(=1.4x1020POT)

Use event rate and Erec spectrum (Same as before)

w/ 3.9% of T2K goal stat.

Best fitsin2223=1.0m2

32=2.45x10-3eV2

Systematic Errors

e sample sample

Flux & X-section 5.0% (22.6%) 4.1%(21.8%)Flux 8.1%(11.9%) 7.1%(10.5%)

X-section (19%) (~19%)

X-sec (non-cancel w/ ND280) 7.5% 6.2%

SK detector 3.0% 10.5%Final-State and Secondary interactions

2.3% 3.5%

total 9.9%(24.2%) 13.2%(25.0%)

() is the case w/o ND280 constraint

Error on #event

w/ Run 1-3 data, both e appearance and disappearance measurements are still statistical limited.However, disappearance is starting to be affected by sys. error effect

Precise measurement of sin2213 by reactor boosts the T2K sensitivity on CP-and octant degeneracy(*).

θ12 = 33.6°±1.0°

θ23 = 45°±6°(90%CL)

θ13 = 9.1°±0.6°

mass hierarchy: unknown

31322

132

232

132

13

212

13231223122

132

232

122

232

122

132

12

21313223131223122

13

21313223131223122313122

13

2132

3131

2223

213

213

sincos4

)21(8

sin)cos2(4

sinsinsinsin8

sinsincos)cos(8

2121sin4)(

EaLSSSC

SSSCCSSSCCCS

SSSCCC

SSSCCSSSC

SmaSSCP e

Max. 27% asymmetry by CP phase for 23=45

Leading including matter effect

CP conserving

CP violating

Matter effect

Solar

* disapp. is measuring sin2223 and cannot resolve <45 or >45.

39% for 23=39

to e oscillation probabilityat oscillation maximum

sin2213=0.1, sin2223=1 in vacuumP(e)


sin2213=0.1, sin2223=1, w/ matter effect

Normal Hierarchy

Inverted Hierarchy

P(e)



Normal Hierarchy

Inverted Hierarchy

Lucky SpotsLarge Chance to find CP violation and to resolve MH.

P(e)



T2K (rough) full stat. error+/-1

Normal Hierarchy

Inverted Hierarchy

P(e)



Normal Hierarchy

Inverted Hierarchy

P(e)


CP allowed region



Normal Hierarchy

Inverted Hierarchy

P(e)




Normal Hierarchy

Inverted Hierarchy

P(e)


CP allowed region



Normal Hierarchy

Inverted Hierarchy

P(e)


CP allowed region

Dotted : NOvA(US, 810km)



Normal Hierarchy

Inverted Hierarchy

P(e)


CP allowed region

Dotted : NOvA(US, 810km)

NOvA Allowed region



Normal Hierarchy

Inverted Hierarchy

P(e)


CP allowed region

Dotted : NOvA

NOvA Allowed region

T2K+NOvA allowed region

Actually, w/ 23 uncertainty

Normal Hierarchy

Inverted Hierarchy

P(e)

Uncertainty by 23(current 1

23 measurement is also(or more) important.

31322

132

232

132

13

212

13231223122

132

232

122

232

122

132

12

21313223131223122

13

21313223131223122313122

13

2132

3131

2223

213

213

sincos4

)21(8

sin)cos2(4

sinsinsinsin8

sinsincos)cos(8

2121sin4)(

EaLSSSC

SSSCCSSSCCCS

SSSCCC

SSSCCSSSC

SmaSSCP e

Max. 27% asymmetry by CP phase for 23=45

Leading including matter effect

CP conserving

CP violating

Matter effect

Solar

39% for 23=39

sin*29.0

sin21(21

sin2

)()()()(

23

23

2132

31

21

13

1212

23

23

SC

SmaS

SCSC

PPPP

ee

ee

,2.8g/cm assuming IH)for - and NHfor ( 1676.0)(

212

)()()(

3

22132

31

2

KTNOvA

matternoe

KTe

NOvAe

aaSm

PPP

T2K-NOvA asymmetry

T2K [email protected] POT(750kW x 5e7sec @ 30GeV)

Combined 3 Flavor Appearance and Disappearance Fit

w/ and w/o reactor results

– sin2213=0.10.005: marginalize by error(=reactor sys. error)

w/ and w/o current systematic error

– Assume same error for anti- mode. +10% overall normalization error.

-mode:anti- mode running ratio =50%:50% for case study

(以下は、主に、Megan Friend(KEK), 池田一得(京大)とCSUの若者の仕事)

Reconstructed Energy Spectrae appearance sample disappearance sample

anti mode

=0, sin2223=1m2=2.4x10-7 eV2

:anti-=50%:50% case mode 106 signal events, 39 bkg. eventsanti- mode 24 signal events, 22 bkg events (5.6 from e)

mode

T2K full sensitivityExpected 90% C.L. allowed region

Allowed region assuming NH or IHSolid : w/o systematic errorDashed : w/ current systematic error

CP=-90, sin2223=1.0 Normal Hierarchy

Running fraction

mode:anti- mode = 100%:0% 50%:50%

w/ reactor results

CP measurement!!!

# signal events # bkg events

mode 74 27

anti- mode 25 13

Combination w/NOvA

Baseline length 810 km (c.f. T2K 295km)

Detector Mass 15kT

3.6x1021 POT in 6 years

(Start in May 2013 w/ partial detector)

GLoBES (General Long Baseline Experiment Simulator) is used

c.f. T2K (:anti-=50%:50% case) mode 106 signal events, 39 bkg. eventsanti- mode 24 signal events, 22 bkg events (5.6 from e)

MINOS (2005- 2012) 735kmNOvA (2013-) 819km

(NH case)

Regions where T2K&NOvA has >90% sensitivityRunning fraction mode:anti- mode = 50%:50%

NH casew/ reactor resultsw/o sys. errors

Red: T2KBlue: NOvABlack: T2K+NOvA

CP violation Mass Hierarchy discrimination

T2K sensitive region

IHだと左右反転





NOvA sensitive region






T2K+NOvA sensitive region


Precision(1)

sin2213

=0degMH is assumed to be known(NH). mode: anti- mode=50%:50%

sin22e

Precision on P(e)Effective 2 flavor mixing angle for P(e)(obtained by fixing other oscillation parameters than 13)

Due to the uncertainty of , 23 and m2

32, precision is worse than sin22e

Full statFull stat

w/o sys. err

w/ present sys. err

Cf. Reactor sys. Error ~0.005

Precision(1)

sin223

Full stat

=0degMH is assumed to be known(NH) mode: anti- mode=50%:50%w/ reactor result

w/o sys. err

w/ present sys. err

stat.only

90%

90%

3

3

Current 90% Allowed region

Inside this band,not resolved.

stat. only

0

1E+21

2E+21

3E+21

4E+21

5E+21

6E+21

7E+21

8E+21

9E+21

1E+22

Guesstimate on accumulated protons on targetand T2K milestones for coming years

LINAC Energy upgrade 400MeV MR rep. rate upgrade 1.28 sec cycle

Full stat.

5 for e appearance

No sys. err

90% for 23 octant

90% for CPv

2 for CPv

Starting point corresponds to sin223=0.39 (current 90% C.L. limit)

90% for non-max. 23

3 for non-max. 23

あまり科学的な図では、ありません。お楽しみということで。

J-PARC power upgrade plan

Ion source & RFQ upgrade

30mA →50mA

LINAC 180MeV→400MeV

FY13 summer 6months shutdown

Rep. rate 2.48s →1.28sReplace all magnet power supplyRF accelerating power upgrade

Upgrade of related pulse operation devices (inj./ext. kicker/septum etc)

Achieve 750kW at ~2017

)sin,cos(

10000

0010

0

00

001U 1212

1212

1313

1313

2323

2323PMNS

ijijijij

i

i

sc

cssc

ces

esc

cssc

研究の目的

! 0.6 1.9)CL%90( 645

0.16.33

13

23

12

~7.6x10-

5eV2

~7.6x10-

5eV2

~2.4x10-3eV2

~2.4x10-3eV2

Normal

OR

Mass Hierarchy

Inverted

Big Impact on 0 double- decay search(hence on Majorana confirmation)

Reactor experiments

CP phaseKEY to understand the origin of matter dominant universe Mixing matrix for

leptons

研究計画

加速器とニュートリノビームの強度向上（定常値! 500 kW、最高値750 kW相当）、

(2) ニュートリノビームフラックスの高精度測定（3 %）

(3) 複数のニュートリノ反応モードの断面積測定によるニュートリノ原子核反応の基準模型構築

(4) 系統誤差改善(5 %) によるニュートリノ振動解析の高度化

(5) 反ニュートリノビームを用いた反ニュートリノ振動の測定

T2K、まだまだ続きます。

a.k.ichikawa, kyoto university for the t2k...

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