Speaker
Description
The Cherenkov Telescope Array Observatory (CTAO) will play a key role in time-domain and multi-messenger astrophysics, providing rapid and sensitive observations of transient very-high-energy gamma-ray sources. Among these, gamma-ray bursts (GRBs) -- particularly short GRBs -- are of special interest due to their association with compact binary mergers and gravitational-wave events. Being typically located at smaller distances than long GRBs, short GRBs represent promising targets for very-high-energy detection.
However, gravitational-wave and GRB alerts often come with large localization uncertainties, posing a major challenge for Imaging Atmospheric Cherenkov Telescopes. In this context, maximizing the instantaneous field of view becomes crucial to increase the probability of covering the true source position during the early, brightest emission phase.
In this work, we investigate optimized pointing strategies for the follow-up of GRBs with CTAO, considering both multi-messenger alerts from gravitational-wave detectors and multiwavelength triggers from space-based gamma-ray instruments such as Fermi-GBM. We compare the performance of parallel pointing, divergent pointing, and a dedicated wide-field configuration tailored for transient follow-up. Using dedicated Monte Carlo simulations we assess their impact on detection probability, sky coverage, and sensitivity. We discuss how optimized pointing strategies can maximize CTAO’s scientific return in the era of multi-messenger and multiwavelength astronomy.