This special session aims to gather the European and international community of astronomers and physicists who are interested in studying compact binary mergers in both gravitational waves (GWs) and electromagnetic (EM) radiation to investigate astrophysical processes, cosmology and fundamental physics, thanks to the present and future GW detector networks and the most advanced EM facilities.

EAS 2024 will take place about a year after the start of the fourth observing run (O4) of the LIGO-Virgo-KAGRA GW detector network, at a time when the cosmic time-volume surveyed in search for compact binary mergers will have more than doubled with respect to the previous O1+O2+O3 runs combined. This will bring new important information on the mergers of compact binaries that harbor a neutron star, a binary neutron star (BNS) and black hole - neutron star (BHNS) mergers, either in the form of a new tighter constraint on their rate or, hopefully, of new exciting detections. Still, the typically large GW localization regions of such new sources poses a challenge to the searches for EM counterparts, which must be addressed by devising creative and effective strategies.

The focus of this special session will, therefore, be on the lessons learned from the first year of O4 both in terms of compact binary merger science and of strategies that European astronomers can develop in order to overcome the challenges posed by the large GW localization regions and the expected faint and fast-evolving nature of the EM counterparts. The session will also be a place for discussing the future of the field, particularly with new facilities coming online over the next decade, such as the Vera Rubin Observatory, the Cherenkov Telescope Array (CTA), the Square Kilometer Array (SKA), the next-generation GW detectors such as the Einstein Telescope (ET) and, at lower frequencies, the Laser Interferometer Space Antenna (LISA).

Programme

We plan to accept contributions covering the following topics:

• GW EM follow-up strategies and results;
• populations of compact object mergers: modeling and observations;
• structure and dynamics of merger and post-merger ejecta: modeling and EM signatures;
• heavy-element production in compact object mergers;
• fundamental physics enabled by multi-messenger observations;
• observational and theoretical future prospects.

Invited speakers

• Maria Grazia Bernardini (INAF - OAB)
• Patricia Schmidt (Univ. of Birmingham)
• Albert Sneppen (DAWN)
• Marica Branchesi (GSSI), panelist [TBC]
• Tomasz Bulik (Warsaw University), panelist
• Riccardo Ciolfi (INAF - OAPD), panelist
• Tassos Fragos (Geneva), panelist

Scientific organisers

• Nancy Elias Rosa (INAF - OAPD, Italy), co-chair
• Om Sharan Salafia (INAF - OABr, Italy), co-chair
• Daniele Bjørn Malesani (Niels Bohr Institute, Denmark)
• Samantha Oates (Lancaster University, UK)
• Martyna Chruslinska (MPA, Germany)

Contact

eas2024_ss2_soc @ inaf.it