Séminaire spécialisé

jeudi 27 juin 2024 à 14:00

Amphi Georges BESSE

Supernova neutrino searches in Super-Kamiokande

Guillaume Pronost

Kamioka Observatory, ICRR, University of Tokyo

Since SN1987A, we know that supernovae produce burst of neutrinos few minutes to several hours before the electromagnetic burst. The Super-Kamiokande experiment, with its 50 ktons water Cerenkov detector, is the world's most sensitive neutrino detector for the detection of these neutrinos. Due to the neutrino energy and their interaction cross-sections in water, more than 90% of the supernova neutrino signal is expected to consist in inverse β decay (IBD) reactions, producing a positron and a neutron. The recent gadolinium loading in the Super-Kamiokande detector allows to improve the detectability and the purity of an IBD selection, enhancing the potential of supernova neutrino searches.
In Super-Kamiokande, we are monitoring galactic supernova neutrino bursts, detecting such rare events (1~3 per century) could help to improve our understanding of the supernova mechanisms, it would also allow us to provide an early warning to the astronomer community looking for the optical counterpart of the supernova. In case of very close supernova's progenitor (<1kpc), Super-Kamiokande could also detect the neutrino flux produces by the Si-layer burning few hours before the actual supernova. In addition, ∼1 supernova occurs each second in the visible universe, this should leads to a Diffuse Supernova Neutrino Background that we are aiming to discover. In this seminar, we will present the last status of these supernova neutrino searches in Super-Kamiokande.