Thématique : Astroparticules
Neutrinos are unique messengers to study the high-energy Universe as they are neutral and stable, interact weakly and therefore travel directly from their point of creation to the Earth without absorption and path deviation. Nowadays, the sources of very high-energy cosmic rays are still unknown. The detection of a neutrino signal is a direct evidence of the sources and the proof of the hadronic mechanism that produced the cosmic rays.
KM3NeT  is the second-generation neutrino detector in the Mediterranean Sea. It will be distributed in two sites: a low energy site ORCA in France (5 GeV-10 TeV) and a high energy site ARCA in Italy (1 TeV-10 PeV). Both parts will have a sensitivity largely improved compared to ANTARES  at low and high energies. The infrastructure is already deployed in both sites and the first lines have been deployed and taking data since 2019. The completion of the KM3NeT is expected to be achieved around 2025-26. Neutrino astrophysics is a young and an almost unexplored field, which owns much discovery potentials. IceCube, a complementary neutrino detector in the South Pole has already discovered the first cosmic neutrinos. This guarantees to have neutrino signal detections in KM3NeT.
The main goal of the thesis is to develop multi-messenger analyses in the two KM3NeT detectors. During this PhD implementation of the efficient all-flavour neutrino selection over the atmospheric backgrounds is foreseen. These neutrino streams can then be used to look for time and space correlation with external triggers from electromagnetic transients, gravitational waves and high-energy neutrinos. For the most interesting neutrinos, the PhD student will also participate to the development of the alert sending system and the multi-wavelength follow-ups (radio, visible, X-ray and VHE).
Thanks to the optical module characteristics, KM3NeT will also be able to detect the MeV neutrino signal from the future galactic supernovae. The participation to the improvement of the supernova analysis is foreseen this PhD thesis too.
The candidate should have a good background in astroparticle physics and astrophysics. The interest in the data analysis is expected together with knowledge of statistics. The analyses will be performed using C++, Python and Root on Linux platforms. This PhD will be co-directed with Vladimir Kulikovksiy from the Genova University  and Damien Dornic from CPPM . The student is expected to pass a significant part in the other laboratory.
 KM3NeT: http://www.km3net.org
 ANTARES: https://antares.in2p3.fr/