Multi-messenger astrophysics with gravitational waves: Einstein Telescope and CTAO synergy

by Biswajit Banerjee (GSSI)

Thursday 27 Mar 2025, 10:00 → 11:00 Europe/Rome

1/3-13 - Sala 313 (Dipartimento di Fisica e Astronomia - Edificio Paolotti)

The Einstein Telescope (ET) is a project of interest for the future of multimessenger astrophysics, and optimization of synergy with astronomical facilities is an essential point. The prompt emission in gamma-ray bursts (GRBs) is usually observed in the 10 keV-10 MeV range. However, to date, in the TeV energies, it has not been detected yet. Although the current generation of very-high-energy (VHE; E > 100 GeV) gamma-ray detectors (MAGIC and H.E.S.S.) has successfully demonstrated the capability of detecting the afterglow of GRB, the prompt phase of detection has remained unexplored. Here, we investigate the perspectives of multi-messenger observations to detect the prompt emission of short GRBs at very-high-energies. Considering binary neutron star merger as progenitor of short GRBs, we evaluate the joint detection efficiency of the Cherenkov Telescope Array observing in synergy with the third generation of gravitational wave detectors. We evaluated taking the expected capabilities to detect and localize gravitational wave events in the inspiral phase and to provide an early warning alert capable of driving the VHE detection. We show that the sensitivities of CTA make it possible to detect the VHE emission even if it is several orders of magnitude fainter than the emission observed in the energy range of 10 keV-10 MeV. In addition, in search of the bright TeV prompt emission, an innovative approach has been proposed for the MAGIC telescopes: responding rapidly to Fermi/GBM triggers to scan the sky localization with short exposures of tens of seconds. The efficiency of covering the number of GRBs per year using this strategy could potentially be adapted for the upcoming CTAO/LST.

In presence and also Zoom Meeting: https://unipd.zoom.us/j/83567909534?pwd=tQrT6126RfObhi3RBa9ioFTVU3M9dn.1