7 papers
Limits on the axion-photon coupling from Chandrayaan-2 observations
Tanmoy Kumar, N. P. S. Mithun, Subhendra Mohanty +3
Axions and axion-like particles (ALPs) have gained immense attention in searches for beyond Standard Model (BSM) physics. Experiments searching for axions leverage their predicted…
Episode-wise spectro-polarimetry of GRB 220107A: Testing the hypothesis of evolving radiation mechanisms
Rahul Gupta, Rushikesh Sonawane, Shabnam Iyyani +17
We investigate the spectro-polarimetric properties of the long-duration GRB~220107A, which exhibited two distinct emission episodes separated by a 40 s quiescent gap, to test wheth…
Time-resolved spectro-polarimetric analysis of extremely bright GRB 230307A: Possible Evidence of evolution from photospheric to synchrotron dominated emission
Soumya Gupta, Rahul Gupta, Tanmoy Chattopadhayay +11
The radiation mechanisms powering Gamma-ray bursts (GRBs) and their physical processes remain one of the unresolved questions in high-energy astrophysics. Spectro-polarimetric obse…
Development of a Compton Imager Setup
Anuraag Arya, Harmanjeet Singh Bilkhu, Sandeep Vishwakarma +16
Hard X-ray photons with energies in the range of hundreds of keV typically undergo Compton scattering when they are incident on a detector. In this process, an incident photon depo…
Spectro-polarimetry of GRB 180427A: evidence for distinct emission sites with varying polarisation
Rushikesh Sonawane, Shabnam Iyyani, Soumya Gupta +5
The dynamics of the origin of gamma-ray emissions in gamma-ray bursts (GRBs) remains an enigma. Through a joint analysis of GRB 180427A, observed by the Fermi Gamma-ray Space Teles…
A Novel Optical Design for Wide-Field Imaging in X-ray Astronomy
Neeraj K. Tiwari, Santosh V. Vadawale, N. P. S. Mithun
Over the decades, astronomical X-ray telescopes have utilized the Wolter type-1 optical design, which provides stigmatic imaging in axial direction but suffers from coma and higher…