Speaker
Description
Binary neutron star (BNS) mergers are the source of most ultrahigh-energy cosmic rays, making them key astrophysical events for multi-messenger studies. The joint detection of gravitational waves (GW170817 by GW detectors) along with spatially coincident short gamma-ray burst (sGRB) GRB170817A has established a clear connection between BNS mergers and sGRBs. In our recent study, we investigate the joint detection probabilities of BNS mergers by GW detectors, specifically for observing run O5 of the LIGO/Virgo/Kagra (LVK) network, with the synergy of upcoming ground-based very-high-energy (VHE) gamma-ray instrument, the Cherenkov Telescope Array (CTA) within 300~Mpc BNS horizon. Assuming the Gaussian structured jet profile and ignoring large sky localization constraints of GW detectors, we estimated VHE afterglow detection probability by CTA. We have comprehensively explored the multi-dimensional afterglow parameter space to identify conditions favourable for detecting GRB afterglow synchrotron self-Compton emission by CTA. The estimated joint detection event rate varies significantly with afterglow parameter distributions, ranging from 0.003 to 0.5 per year. We also estimate the high-energy neutrino flux from afterglow emissions of those events jointly detected by CTA and LIGO. Further, we calculate the rate of neutrino detection from individual sGRBs at the luminosity distance and the total kinetic energy of the blast wave, which is most probable for joint detection. Finally, we determine the detection upper limit for neutrino flux for the currently operating neutrino detectors.