High Energy Physics Seminars

Search for very high energy gamma-ray emission from galactic sources & development of calibration system for future imaging telescope.

by Mr. Anshu Chatterjee (Saha Institute of Nuclear Physics, Kolkata)

Thursday, June 20, 2019 from to (Asia/Kolkata)
at TIFR, Mumbai ( AG-80 )
In recent years substantial experimental and theoretical efforts have been done to investigate the physics issues involved in most energetic phenomena of our galaxy and beyond it. Gamma-ray astronomy offers an effective way to explore the fundamental physical processes behind these energetic phenomena. In searching for galactic gamma-rays and origin of galactic cosmic rays, different types of possible galactic sources have been studied in this work. This includes Supernova Remnant (SNR), Pulsar Wind Nebulae (PWNe) and some dark sources (detected in TeV range with water Cherenkov detector) which have no other counter part in lower wavelength regimes. Based on both source energetics and characteristics, hadronic or leptonic model have been applied to explain the observed broad band spectrum. To explore source characteristics over wide energy range (few tens of MeV to hundreds of TeV), data of three gamma-ray observatories, i.e. Fermi-LAT, Major Atmospheric Gamma Imaging Cherenkov (MAGIC) telescopes and High Altitude Water Cherenkov (HAWC) Observatory, are presented here. In spite of rigorous efforts, some of these sources still remain undetectable due to the constraint of sensitivity of current generation of imaging atmospheric Cherenkov (IAC) telescopes and ended with upper limit in ux calculation. The Cherenkov Telescope Array (CTA) is an international collaboration to build next generation IAC telescope which is expected to provide 10 times better sensitivity than the present IACTs over a wide energy range from 20 GeV to 300 TeV. In the second part of the talk, the development of a calibration system for large size telescope (LST) of CTA will be presented.