Speaker
Description
The Imaging Atmospheric Cherenkov Technique (IACT) is the standard method for ground-based
detection of very-high-energy gamma rays from astrophysical sources. IACT telescopes record very
short duration flashes of Cherenkov light produced in extensive air showers initiated by gamma and
cosmic rays entering the Earth’s atmosphere. Traditionally, photomultiplier tubes (PMTs) have been
the dominant choice as photon sensors for IACT cameras. However, recent advances in solid-state
detector technology have made silicon photomultipliers (SiPMs) a viable alternative, offering several
advantages over PMTs.
Our group at TIFR Mumbai has developed a 256-pixel imaging camera based on SiPM technology for
a 4 m class imaging atmospheric Cherenkov telescope. The camera uses SiPMs as pixel-level
photosensors and features a modular data acquisition architecture that enables rapid development,
scalability, and easy maintenance. The front-end electronics condition the pixel signals and provide
load and temperature compensated bias voltages to the SiPMs. The conditioned analog signals are
then routed to the back-end electronics for high-speed sampling, trigger generation, digitization, and
data transfer to an event-builder PC for offline analysis. Pulse digitization is performed using the DRS4
analog sampling chip for ultra-fast waveform acquisition. The camera configuration, operation, and
data acquisition are managed through a suite of in-house developed firmware and software.
This talk will present the design and implementation of the camera data acquisition system, and
associated software framework.