Welcome to Physics Group
Variable Energy Cyclotron Centre, Kolkata

Electronics for STAR PMD at BNL-USA

Readout for PHOTON MULTIPLICITY DETECTOR (PMD) in STAR involves reading 82K channels from anode wires of gas proportional chambers. The processing of PMD signals is carried out by a Gas-4 board comprising 4 Gassiplex chips. The detector signals are coupled to this GAS-4 board in a group of 64 by a 70 pin SAMTEC connector. Each of the 4 Gassiplex consistsof 16 channels each with a CSA, de convolution filter, Shaper, TRACK/HOLD, buffer and an analog multiplexer and buffer and reads 64 channels. Two types of GAS-4 boards have been designed for use with detector modules which are rhombus shaped in geometry. The GAS-4 boards have been designed to plug protection boards with diodes. These boards protect the Gassiplex against possible sparks in the detector.

Electronics for ALICE PMD at CERN, GENEVA

Readout for PHOTON MULTIPLICITY DETECTOR (PMD) in ALICE involves reading 200K signals from anode wires of gas proportional chambers. The detector signals are coupled to the FEE board (6 Layer PCB)through flexible kapton PCB in a group of 32.The processing of PMD signals is carried out by a FEE BOARD comprising 4 MANAS CHIPS,2 buffer amplifiers, 2 serial 12 bit ADCs (AD7476) & custom built ASIC called MARC( Muon Arm Readout Chip). Each of the 16 channels MANAS consists of CSA, deconvolution filter, Shaper, TRACK/HOLD, buffer and an analog multiplexer. MARC controls 4 MANAS CHIPS, 2 ADCS and performs Zero suppression on data and communicates with DSPs through 4 bit bus. 32 bit word is sent by Link port bus in 8 nibbles of 4 bits each. DATA ACQUISITION is done by a cluster of DSPs called CROCUS (Cluster Readout & Concentrator Unit Systems).

Electronics for CBM experiment at GSI Darmstadt

VECC will develop a large part of the Muon detection at the CBM experiment in upcoming FAIR facility. The jobs involved are R&D and fabrication of fast and high resolution gaseous detectors using GEM and associated fast and high density electronics. The readout to be used for CBM is based on self-triggered concept with associated time stamp. Future activity of the section will include design and building of chamber printed circuit boards and associated electronic boards.A 2 Chip Front End Board reads 256 signals from GEM detectors. The top and bottom Copper of 8 layers PCB with 2 NXYTER chips is shown below. Each NXYTER reads 128 signals. The GEM detectors can also be tested with FEE boards comprising MANAS and designed for ALICE PMD.

Nuclear Instrument Modules for low energy experiments for VECC

A current Integrator has been developed that is used in Control room of VECC to measure beam currents in the range of 1nA to 1mA. A Charge Sensitive Amplifier (CSA) and dual gate and delay generators have been designed for the use of experimentalists in our centre.

 Photograph of the current integrator

Forward Calorimeter in ALICE

For the proposed Forward calorimeter (FoCAL) in ALICE,a new detector system using silicon PAD detectors is being worked out. We plan to procure with the help of Electronics Division BARC, which will develop (6 x 6) 1 cm2 silicon Pad detector at CMEMS Centre and fabricated by BEL (Bharat Electronics Limited). Total 50 detector arrays will be fabricated for the first prototype. We plan to use both INDIPLEX and GASSIPLEX for the readout purpose. The FEE boards designed for use in ALICE PMD comprising MANAS can be modified for use with Gassiplex chips and operating in silicon mode to take advantage of higher dynamic range in this mode. Necessary modifications are being done on the readout boards for this purpose. Also we plan to design a new fee board with INDIPLEX which is developed by Electronics Division BARC.