Development of SciFi/CheFi detectors with SiPM readoutKen Suzuki1, Stefan Fossati1, Matthias Schafhauser1,Johann Marton1, Paul Bühler1, Johann Zmeskal1

1 Stefan Meyer Institute of Austrian Academy of Sciences, Vienna

Stefan Meyer Institut für subatomare PhysikÖsterreichsche Akademie der Wissenschaften

http://www.oeaw.ac.at/smi

Ken Suzuki <ken.suzuki@oeaw.ac.at>

Boltzmanngasse 3, A-1090, Vienna, Austria

Multi-pixel Geiger-mode Avalanche Photo Diode

= Silicon Photo Multiplier

PMT has been a great friend of nuclear/particle physicist for many years in photo sensing �eld . Recently new type of Avalanche Photo Diode started to compete with PMT. It’s operated in a Geiger-mode and has multiple pixels.

PMT SiPMGain ~106 105~6

Bias Voltage 1-2k 20~100

Dark Count low high

Cost ~800 ~80

Size 1inch< 1mm2 ~ 10mm2

Magnetic Field sensitive (< 1mT) insensitive (< 15T)

P.D.E. ~0.25 0.25~0.65

Comparison of PMT and SiPM

Hamamatsu S10362-11-100U

minimum IOR of standard cladding material (Flouracrylic)

IOR of Fiber Core

Max

. IO

R o

f cla

ddin

g fo

r tot

al re

flect

ion

1.4 1.6 1.8 2.0

0.8

1.0

1.2

1.4

1.6

proton at 3.0GeVpion at 1.15GeV/cpion at 1.7GeV/c

Teflon®AF

Plexi Glass

IOR for total reflection

Lead Glass

Vacuum

proton or pion~0.95 ch

n2

n1

n1

n2

Photon Counting with SiPM

Hamamatsu S10362-11-100U

Fiber ConfigurationSquare

Trapping Efficiency 7.3% @ double clad.

Cladding Thickness 2% of fiber size

Fiber Configuration

Material Thickness 4mm = 8ppm of X0

0=1.4mrad for p@1GeV/c

1mm

Number of Photons

Momentum [MeV/c]

Num

ber o

f pho

ton

0 1000 2000 3000 0

1000

2000

3000

4000

5000

6000

Proton

Pion

Kaon

for 1mm Plastic Scintillator

Simulation code: leps

20~30 photon electrons at SiPM

0

2

4

6

8

10

12

14

16

18

37 38 39 40 41 42 43 44 45 46

U bias [V]

I leak

[A]

0.3°C

4.4°C

9.4°C

15.0°C

20.1°C

25.0°C

Ileak vs T (SSPM050701)

1,0E-02

1,0E-01

1,0E+00

1,0E+01

0,0 5,0 10,0 15,0 20,0 25,0 30,0

T [°C]

I leak

[A]

38V

39V

40V

41V

42V

43V

0

10

20

30

40

50

60

67,5 68,0 68,5 69,0 69,5 70,0 70,5 71,0 71,5 72,0

U bias [V]

I lea

k [

A]

0.6°C

4.7°C

10.1°C

15.1°C

20.0°C

24.9°C

Ileak vs T

0,01

0,1

1

10

100

0,0 5,0 10,0 15,0 20,0 25,0

T/°C

Ileak

/A

U=69V

U=69.5V

U=70V

U=70.5V

U=71V

10m

v/di

v

15mv

SiPM: Photonique SSPM_050107GR_TO18

Vbias: 40V

1 p.e.

2 p.e.

3 p.e.

4 p.e.

5 p.e.

Preamp: Photonique

1 p.e. noise

10ns/div

Application 1: Scintillating �ber with SiPM readoutLeakage current measurement

Each pixel functions as independent Geiger tube, the outputs of all pixels are connected in parallelwhich results in excellent photon counting capability

It can be operated with much lower voltages than PMT. It can be operated under extreme magnetic�eld. They are great advantages. It is very compact. This can be also a unique feature.

SiPMs from two manufacturers show totally di�erent behavior at around break-down voltages.Break-down voltage is strongly temperature dependent.

This nature requires active regulation on temperature and careful operation of voltage.

Hamamatsu S10362-11-50UPhotonique SSPM050701

Compact size of SiPM matches perfectly with Scintillating �ber readout. Sensitive area canbe easily large which Silicon strip detector cannot cover. Self-triggerable as an advantageover gas chamber

Beam pro�le monitor, (Lambda trigger counter) based on that idea are under construction

Application 2: Cherenkov �ber detector with SiPM readoutfor high rate fast timing counter under magnetic �eld

Timing resolution of ordenary counter like scintillator+PMT is normallydetermined by statistical e�ect of photon production process, di�erentlight path, PMT signal rise time...

These detectors being developped will be used in an experimet

„Kaonic nuclear cluster“ search at FOPI/GSI in the reactionp + p K−pp + K+ @ Tp=3.0GeV

In order to ful�ll the total re�ection condition, either a combination of higely doped Lead Glass+Te�on® AF, or just radiator rod in a vacuum.

Λ + p

π− + p

-1.0 0.0 1.0 2.0-2.0

distance [fm]

K density(arbitrary)

-

.

p-p distance = 2.0 fm

1.35 f

m

1.36 fmrms distance

1.90 fmrms distance

[3] K. Suzuki, FOPI Collaboration Meeting, 2007

[4] Y. Akaishi and T. Yamazaki, Phys. Rev. C 65 (2002) 44005

[5] T. Yamazaki and A. Yamazaki, Phys. Rev. C 76 (2007) 45201

[6] Experimental Proposal to GSI (2007)

“Kaonic nuclear cluster” is an antikaon - nucleusbound system formed by strong attractive KN interaction.

Antikaon sits at the center of the system and compresswhole system --> “cluster”

01020304050

0 1 2 30

1020304050

0 1 2 30

1020304050

0 1 2 3

p from ppK - p from Λ π from Λ

θlab

(deg

)

θlab

(deg

)

θlab

(deg

)

Momentum (GeV/c) Momentum (GeV/c) Momentum (GeV/c)

Central Detectors

ForwardDetectors

K th

eta

lab

(deg

)

+

80

70

60

50

40

30

20

10

2.52.01.51.00.500

K Momentum (GeV/c)+

p + p ppK + K @Tp=4.5GeVv +-p + p ppK + K @Tp=4.0GeVv +-p + p ppK + K @Tp=3.5GeVv +-p + p ppK + K @Tp=3.0GeVv +-

Barrel AcceptanceRPC Acceptance

[1] Multi-Pixel Photon Counter, Hamamatsu Photonics, Jan 2007

[1]

[2] S. Fossati, M. Schafhauser et al., unpublished

[2]

Δ(dark count) / 9deg = 10% Δ(dark count) / 9deg = 50%

[3]

Beam Pro�le Monitor

z

y

1 m

Start CounterTarget (LH2)

Veto Counter

Lambda Trigger Counters

Central DC Forward DC

TOF Barrel (RPC)TOF Barrel (plastic) TOF Wall (plastic)

proton beamTp=3.0GeV, I=107/s

2000 2100 2200 2300 2400 25000.00

0.01

0.02

0.03

MppK- [MeV/c2]

p+p ppK - + K+ @ Tp=3.0GeVv

d2σ

/dΩ

dM [μ

b/sr

/MeV

]

θlab = 0.0ºθlab = 10.0ºθlab = 20.0ºθlab = 30.0ºθlab = 40.0º

p + p --> K + p + Λ+ *

p

p

K+

p*Λ*Λ

p

In the process p+p-> [p+Λ(1405)] + K+ where Λ(1405) behaves as a “door-way” to such compact system.

Λ(1405) as a bound state of proton and antikaon(BE.=27MeV, Γ=40MeV) as the core Ansatz

Experimental Setup

From pp reaction Λ(1405) is created always at shortdistance to the proton, and due to its high density the momentum transfer (Δq~1.6 GeV/c) stays appro-priate region to trap the proton, and therefore a large cross section is expected.

Up to ~8 photons, the number of photons is discretely counted in a charge spectrum

[3]

[4]

[5]

[6]Experimental Task is to detect and identify all decayed particles from ppK− (Invariant Mass Spectroscopy) and to detect K+ for missing mass spectroscopy

Invariant Mass SpectroscopyPhase space distribution of ppK− decayed particles and acceptance

Missing Mass SpectroscopyPhase space distribution of K+ and acceptance

Fast photon production process of Cherenkov e�ect to match with the fast pulse output of the SiPM.

Beamline TOF-start counter with decent timing resolution (<100ps) which works for MIP, high rate (<107Hz) under magnetic �eld is required.

Financial supports of this work by INTAS (Ref. Nr. 05-1000008-8114) and the EU Project DIRACsecondarybeams are greatfully acknowledged