Enabling real-time multi-messenger follow-up of transient events with Astro-COLIBRI

Abstract: Time-domain astrophysics is a rapidly growing field focused on the study of transient phenomena such as Gamma-Ray Bursts (GRBs), Fast Radio Bursts (FRBs), supernovae, novae, and AGN flares. Their characterization increasingly relies on a multi-messenger and multi-wavelength approach, combining gravitational waves, high-energy neutrinos, and electromagnetic observations across the spectrum. Such a coordinated strategy requires efficient information sharing and thus tools capable of rapidly compiling and contextualizing key data for each new event. We present Astro-COLIBRI, a well-established platform designed to meet this challenge. Astro-COLIBRI combines a public RESTful API, real-time databases, and a cloud-based alert system. It continuously listens to multiple alert streams, applies user-defined filters, and places each event in its multi-messenger and multi-wavelength context. Through its user-friendly interfaces, including a web application and mobile apps for iOS and Android, the platform provides clear data visualization as well as concise summaries of key event properties and observing conditions for user-defined locations.