P1-0031 Multimessenger astrophysics (2022-2027)

Research program P1-0031 Multi-messenger astrophysics is oriented towards obtaining a more complete, unified picture of the Universe, its constituents, their interactions and high-energy processes. Combining the information carried by different cosmic messengers: photons, charged cosmic particles, neutrinos and gravitational waves, is the key for achieving this objective.

The primary program goal is to investigate phenomena related to extreme energies in nature and push forward the knowledge frontier. With our active participation in leading international research collaborations in this field we will contribute to cutting-edge science in searches for extremely energetic astrophysical sources, transient astrophysical phenomena, dark matter and possible mechanisms responsible for the matter – anti-matter asymmetry in the Universe. The results of this work are expected to be extremely relevant for science in general and in particular for the fields of astro- and elementary particle physics, astrophysics and cosmology.

The research of ultra-high energy cosmic particles (UHECR) will be pursued within the Pierre Auger Collaboration. It has insofar led to major breakthroughs, such as the evidence for the suppression of the UHECR flux above 55 EeV and UHECR extragalactic origin. Major open questions still remain, such as particle composition of the UHECR flux and the identity of their sources. To facilitate the identification of the primary UHECR, the observatory is being substantially upgraded (AugerPrime). We will take an active role in the AugerPrime science activities, focusing on the composition and anisotropy studies of the highest-energy particles.

The research of high (HE, ≳ 20 MeV) and very high (VHE, ≳ 20 GeV) energy gamma rays will continue to be pursued within the Fermi Large Area Telescope (LAT) Collaboration and the Cherenkov Telescope Array (CTA) Observatory. LAT is the leading space laboratory for HE gamma ray research, while the emerging CTA will provide full-sky coverage for VHE gamma-rays with improved sensitivity, angular and energy resolution with respect to present experiments. Our scientific activities within LAT and CTA are expected to bring significant advances in the studies of cosmic ray sources, gamma-ray interactions with interstellar medium, the properties of black hole particle accelerators, and dark matter searches.

The research of astrophysical transient sources, which include tidal disruption events in vicinity of black holes, gravitational wave events, gamma ray bursts, and supernovae, is another essential component of multi-messenger astrophysics, expected to bring important new insights in various fields. These activities will be conducted through our involvement in the Vera C. Rubin Observatory’s Legacy Survey of Space and Time (LSST), Gaia Science Alerts, Liverpool Telescope, and ENGRAVE collaborations.