Gamma Ray sky; Credit: Fermi Telescope, 5 years data
Gamma Ray sky; Credit: Fermi Telescope, 5 years data
Theoretical Study: The inverse Compton scattering of the cosmic microwave background radiations was found to overproduce the gamma-ray emission, observed by FERMI LAT in 2013, at GeV energies from the large-scale jet of quasar 3C 273. Considering a broken power-law spectrum of the accelerated protons in the jet we showed that the synchrotron emission from this population could explain the observed X-ray to the gamma-ray flux from knot A (Kundu and Gupta 2014b, MNRAS Letters, 444, L16 - L19 ).
Another popular gamma-ray source is Centaurus A. In 2013, a new component in the gamma-ray spectrum from the core of this object was reported in the energy range of 4 GeV to tens of GeV. We showed that this new component and the HESS detected spectrum of gamma-rays from the core at higher energy had possibly a common origin in the photo-disintegration of heavy nuclei (Kundu and Gupta 2014a, JCAP, 04).
I will resume working on this area in the near future!