Congrès de l'ACP / CAP Congress

Dr. Sébastien Bianchin (TRIUMF / UBC)

Development of an Active Kaon Stopping Target for the TREK-E36 Experiment at

J-PARC

29 Mai 2013 / May 29, 2013

S. Bianchin CAP Congress (May 27 - 31, 2013) 2

The TREK-E36 Experiment

The TREK-E36 Experiment at J-PARC is dedicated to the search for lepton flavor universality violation in Γ(Ke2)/Γ(Kµ2)

Talk by Prof. M. Hasinoff R2-7-4 (Thurday, May 30)

Precise measurement of the decay width ratio: RK = Γ(Ke2) / Γ(Kµ2)

E36 Goal : δRK/RK = ± 0.2% (stat.) ± 0.15% (syst.) [0.25% total]

S. Bianchin CAP Congress (May 27 - 31, 2013)

Active Polarimeter(JAPAN)

New Fiber Target(CANADA)

GEM Dectectors(USA)

CsI(Tl) readout (RUSSIA)

End View Side View

The TREK Experimental Apparatus

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S. Bianchin CAP Congress (May 27 - 31, 2013)

18 Fibres (~6cm)

The TREK Scintillating Fiber Target

● 256 Fibers (3.2 x 3.2 x 200 mm3)

● Tested (Nov. 2012), labelled and ready to be assembled

● 1mm groove + green WLS fiber glued

● Assembly starts in May 2013 (K. Chang)

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S. Bianchin CAP Congress (May 27 - 31, 2013) 4

18 Fibres (~6cm)

The TREK Scintillating Fiber Target

● 256 Fibers (3.2 x 3.2 x 200 mm3)

● Tested (Nov. 2012), labelled and ready to be assembled

● 1mm groove + green WLS fiber glued

● Assembly starts in May 2013 (K. Chang)

S. Bianchin CAP Congress (May 27 - 31, 2013)

Production of the TREK Fibers

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1. A 1mm wide groove is cut along the 20cm long scintillating fiber

S. Bianchin CAP Congress (May 27 - 31, 2013)

Production of the TREK Fibers

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1. A 1mm wide groove is cut along the 20cm long scintillating fiber

2. An optical glue is carefully deposited inside the groove

S. Bianchin CAP Congress (May 27 - 31, 2013)

Production of the TREK Fibers

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1. A 1mm wide groove is cut along the 20cm long scintillating fiber

2. An optical glue is carefully deposited inside the groove

3. A green WLS fiber is pushed inside the groove and let to rest for 24h so that the optical glue hardens

S. Bianchin CAP Congress (May 27 - 31, 2013)

Production of the TREK Fibers

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1. A 1mm wide groove is cut along the 20cm long scintillating fiber

2. An optical glue is carefully deposited inside the groove

3. A green WLS fiber is pushed inside the groove and let to rest for 24h so that the optical glue hardens

4. A plastic coupler is glued at the other end of the green WLS fiber

S. Bianchin CAP Congress (May 27 - 31, 2013)

Fibers are held together by stepped acrylic pieces and 1mm-thick Aluminium rings

7mm clearance to Aerogel Tube

Aerogel Tube : ID 79mm OD 85mm

Target Tube : ID 57mm OD 65mm

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The TREK Scintillating Fiber Target

Side View

Acrylic pieces at both ends of the target

S. Bianchin CAP Congress (May 27 - 31, 2013)

● MPPCs (S10362-11-50C)● 1 x 1 mm2 sensor● 400 Pixels (50x50 µm2)● Gain: 7.5x105

● Better efficiency at low temperatures (0-5°C)

● ~450 MMPCs have been tested (Nov. 2012)

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The MMPC Readout

S. Bianchin CAP Congress (May 27 - 31, 2013)

The Complete Setup (Concept)

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Target OUT

Target IN

Temporary Support

S. Bianchin CAP Congress (May 27 - 31, 2013) 8

The Complete Setup (Concept)

Target IN

S. Bianchin CAP Congress (May 27 - 31, 2013)

The TREK Dark Box

Made of G10 (light tight)

568

mm

568

mm

The green WLS fibers are installed through a slot in the Dark Box upstream plate

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S. Bianchin CAP Congress (May 27 - 31, 2013)

The EASIROC Board

● 32-channel I/O

● DSP / FPGA

● ADC (HG and LG)

● Multi Hit TDC (LE and TE)

8x 32 channel (or 4 x 64) EASIROC boards are needed to read out the 256 channels (full target)

Designed and made in Japan

Tested at TRIUMF

A new 64 channel EASIROC board is currently being designed and

should be ready for tests in 2014 !

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S. Bianchin CAP Congress (May 27 - 31, 2013)

Beam Tests & Preliminary ResultsTests performed at TRIUMF (Nov. 2012)

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S. Bianchin CAP Congress (May 27 - 31, 2013)

Beam Tests & Preliminary ResultsTests performed at TRIUMF (Nov. 2012)

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S. Bianchin CAP Congress (May 27 - 31, 2013)

A Look Inside de Box

32 (8x4) Fiber Bundle (~24x12mm2)

Hit in perpendicular AND parallel directions

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S. Bianchin CAP Congress (May 27 - 31, 2013)

A Look Inside de Box

32 green WLS fibers coupled to 32 MPPCs

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S. Bianchin CAP Congress (May 27 - 31, 2013)

Preliminary Results : ADC Spectra

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EA

SIR

OC

Bo

ard

#1

EA

SIR

OC

Bo

ard

#2

Missing Channels (#14 & #28)

S. Bianchin CAP Congress (May 27 - 31, 2013)

Temperature dependence of ADC Gain

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S. Bianchin CAP Congress (May 27 - 31, 2013)

Temperature dependence of ADC Gain

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S. Bianchin CAP Congress (May 27 - 31, 2013)

Temperature dependence of ADC Gain

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S. Bianchin CAP Congress (May 27 - 31, 2013)

Temperature dependence of ADC Gain

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courtesy of F. Retière

∆x = -22.95T + 362.6

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1 pe ~12.5 pe

Dark Curent Analysis

Average Energy Deposit through 3mm of plastic 0.6 MeV

~21 pe/MeV

ped

1 pe

2 pe

MPPC noise spectrum showing the photo-electron separation

3 pe

Energy spectrum for penetrating cosmic rays passing through 1 bar

S. Bianchin CAP Congress (May 27 - 31, 2013)

Preliminary Results : Particle Tracking

beam

beam

EA

SIR

OC

Bo

ard

#1

EA

SIR

OC

Bo

ard

#1

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S. Bianchin CAP Congress (May 27 - 31, 2013)

Preliminary Results : Particle Tracking

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beam

beam

EA

SIR

OC

Bo

ard

#2

EA

SIR

OC

Bo

ard

#2

S. Bianchin CAP Congress (May 27 - 31, 2013)

beam

beam

EA

SIR

OC

Bo

ard

#2

EA

SIR

OC

Bo

ard

#2

Preliminary Results : Particle Tracking

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S. Bianchin CAP Congress (May 27 - 31, 2013)

Tracking Algorithm

We built a set of 20 “perfect” tracks in

a 64 fiber bundle

and

tested our tracking algorithm

Prelim

inary

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S. Bianchin CAP Congress (May 27 - 31, 2013)

Tracking Algorithm

Prelim

inary

We are now working on a better version of our tracking algorithm capable of finding the particle tracks for MC simulated events and later on for real data collected during our beam tests

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courtesy of D. Gill

S. Bianchin CAP Congress (May 27 - 31, 2013)

The TREK Collaboration

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