Detector development and physics studies in high energy physics

experiments

Shashikant Dugad

Department of High Energy Physics Review,

3-9 Jan 2008

Motivation

• DAE-DST Vision meeting (7-8 April 2006)– Need for core detector development

Silicon Photomultiplier Water Cherenkov with WLS Readout

GRAPES Muon/HCAL

Imaging γ-ray TelescopeMACE(BARC)

ILC-HCAL

INO-ECAL

Space experiment?(ISRO)

Tracking Detector Muon detector for GRAPES

Calorimeter HCAL for GRAPES ECAL for INO?

Many Other applications Experimental nuclear physics Imaging

Photo Devices

Large gain (106)

Cost prohibitive for large scale requirement

Sensitive to magnetic field

Occupies large volume

Low gain (~100) solid state device

Cost not as high as PMT

In-sensitive to magnetic field

Occupies small volume

Small gain (~1000) solid state device

Cost as high as PMT

In-sensitive to magnetic field

Occupies small volume

PMT APD HPD

Silicon Photomultiplier Low cost, high gain, fast timing device

SiPM

• APD operated above breakdown voltage– Geiger response mode

• Essentially a logical device– converted to photon counting by having large array of

such diodes in small area

APD SiPM

Typical design• A micropixel of SiPM has a drift region at few micron epitaxy layer on low resistive P

substrate.

• PN junction in epitaxy layer provides a depletion region with high electric field where

Geiger mode discharge occurs with incoming photons.

• Electrical decoupling of the pixels provided by silicon resistive strips.

• Uniformity of the electric field within a pixel by n- guard rings or trench.

• All micropixels is connected by common Al strip to readout.

• Gain ~106 @ ~50 V working bias

• Low electronic noise

• -> Noise: Dark rate(~2 Mhz) is originated from thermally produced charge carriers

Electrical decoupling to readout the signal

Uniformity of the electric field

2

Drift region

1

N+

P+

Phos ~1017

Boron ~1015

Doping profileElectric field

Geiger region

106

102

104

0

E, (V

/cm

)

x (um)Electric field distribution in epitaxy

layer

Topology of SiPM

• Hye-Young Lee

MIP With SiPM in HO-CMS

SiPM development plan

• SiPM characterization facility– In progress at Ooty with help from HCAL-CMS collaboration

• Packaging and assembly of the device – In progress with Bharat Electronics Limited (BEL)

• Device and Process Simulation, Fabrication– BEL, Banglore

– Semiconductor Complex Limited, Chandigarh

MSOAmplifierSiPM

Initial Setup for SiPM Study at Ooty

Characterization of CPTA-SiPM

Team

• BARCBARC– Chandratre etal.Chandratre etal.

• Expertise in device developmentExpertise in device development– Choudhary etal.Choudhary etal.

• Radiation testsRadiation tests

• ISROISRO– Discussions with Dr. Sreekumar in progressDiscussions with Dr. Sreekumar in progress

• TIFRTIFR– Sudeshna Banerjee, S.R. Dugad, S.K. Gupta, P.K. MohantySudeshna Banerjee, S.R. Dugad, S.K. Gupta, P.K. Mohanty– Jagadeesan, A. Jain, S. Karthikeyan, K. Manjunath ...Jagadeesan, A. Jain, S. Karthikeyan, K. Manjunath ...

Water Cherenkov (WC) Detectors

• This technique is in use in detection of muons, electrons etc.

(GRAPES Ooty, Kamioka, AUGER …)

• WC detector used at Ooty has good timing response but poor

uniformity with no directinality

• Plans to make WC detector with good uniformity, timing and

directionality– If we succeed then it can be used as an alternative to scintillators in

large air shower array for measuring electromagnetic component

– Muon detector with good angular resolution

– Hadron/Electromagnetic Calorimeter for GRAPES/INO

Design

• Rectangular tube filled with distilled water doped with popop

• Several WLS fibers anchored along the length which carries photons to photo device

• Dimension: 50x4.6x4.6 cm3 with 16 WLS fibers

Photoelectron yield of Water Cherenkov Detector

Timing Response

Summary• Plans

– Silicon Photomultiplier• Characterization laboratory for SiPM

• Develop packaging and assembly line

• Fabricate SiPM

– Water Cherenkov detector• Optimize the performance

• Make prototype tracking detector with PMT/SiPM readout

• Expose it to ~GeV electron beam at INDUS-Indore to validate its calorimetric performance

Performance of SiPM

• Danilov etal.