The AGILE real-time analysis software system to detect short-transient events in the multi-messenger era

AGILE is a space mission launched in 2007 to study X-ray and gamma-ray phenomena through data acquired by different instruments on board the satellite. In the multi-messenger era, the fast detection of transient sources is one of the main goals of space and ground-based gamma-ray observatories. When an observatory detects a transient event, it usually sends science alerts to other facilities through networks such as the General Coordinates Network (GCN), enabling follow-up observations. To achieve this task, real-time analysis (RTA) pipelines are required. This manuscript presents the RTA system developed for the AGILE space mission to detect transient sources on timescales from seconds to one hour. Two types of pipelines are presented. One pipeline executes automated analyses as soon as data are available, sharing the detection of sources with the community; more than 90 automated notices have been sent to the GCN since May 2019. The other pipeline reacts to external science alerts from neutrinos, gravitational waves (GW), etc., to search for electromagnetic counterparts in the AGILE data. The AGILE Team can visualize the results of these analyses using a web platform. The pipelines hereby presented can be a starting point for the development of RTA systems of the next generation of space-based gamma-ray observatories.