Orateur
Description
Multi-wavelength and multi-messenger astrophysics have experienced remarkable growth over the past decade, aiming to build a comprehensive picture of various cosmic phenomena. Transient sources, in particular, greatly benefit from the complementary information provided by multi-messenger observations, both enhancing follow-up of rapidly fading signals and allowing for a better physical understanding of the event.
Gravitational wave (GW) detections act as ideal triggers for searches of electromagnetic counterparts. A GW event may, for instance, be associated with a Gamma-Ray Burst (GRB), a jetted cataclysmic phenomenon produced either by binary neutron star mergers or core-collapse supernovae. Such sources emit across the electromagnetic spectrum, enabling their discovery with X- and gamma-ray space instruments and offering valuable multi-wavelength follow-up opportunities. The need to capture the full temporal evolution of these rapid emissions, coupled with the often broad localization areas of GW alerts, highlights the importance of fast, coordinated response strategies and real-time information tools.
This contribution presents the H.E.S.S. follow-up framework for the GW and GRB alerts. I will show representative follow-up examples, emphasizing key results and challenges in the search for high-energy gamma-ray counterparts. Furthermore, I will introduce Astro-COLIBRI, a dedicated platform for real-time coordination and visualization of multi-messenger information, designed to support rapid response in the time-domain astrophysics era.
