By Luigi Piro (Istituto di Astrofisica e Planetologia Spaziali (IAPS)/INAF(IAPS)/INAF)

On November 27 - 29, 2018 a group of scientists including members of the Athena, VIRGO, LIGO, LISA mission, ICECUBE, KM3NET, THESEUS mision and CTA observatory experts joined at Alicante University (Spain), in a workshop aimed at developing scientific synergies between the Athena X-ray observatory mission and Gravitational Waves, neutrinos, high energy and Gamma-Ray Burst facilities that will be operational contemporary to Athena.

This workshop, organized with the support of the H2020 AHEAD program, was intended to set the stage for a joint study leading to a synergy white paper. Various exciting scientific topics were preliminary identified, dealing primarily with the most energetic phenomena and the largest particle acceleration sites of the Universe. The perspectives of observing electromagnetic counterparts of GW sources such as neutron star mergers and supermassive black holes system at cosmological distances or sources of neutrino and very high energy gamma rays, such as supernovae or jets in AGNs were discussed. The use of Gamma-Ray Bursts as cosmic beacons to explore the high-redshift universe and the cosmological filamentary structure of the hot gas was also a key topic.

The discussion touched also upon the operations required on the different observatories to implement the synergy goals. Planning for the preparation of the white paper was successfully agreed, targeting a release around mid next year, with the technical support of the Athena Community Office.