Pre-supernova Alert System for Super-Kamiokande

Journal article

In 2020, the Super-Kamiokande (SK) experiment moved to a new stage (SK-Gd) in which gadolinium (Gd) sulfate octahydrate was added to the water in the detector, enhancing the efficiency to detect thermal neutrons and consequently improving the sensitivity to low energy electron anti-neutrinos from inverse beta decay (IBD) interactions. SK-Gd has the potential to provide early alerts of incipient core-collapse supernovae through detection of electron anti-neutrinos from thermal and nuclear processes responsible for the cooling of massive stars before the gravitational collapse of their cores. These pre-supernova neutrinos emitted during the silicon burning phase can exceed the energy threshold for IBD reactions. We present the sensitivity of SK-Gd to pre-supernova stars and the techniques used for the development of a pre-supernova alarm based on the detection of these neutrinos in SK, as well as prospects for future SK-Gd phases with higher concentrations of Gd. For the current SK-Gd phase, high-confidence alerts for Betelgeuse could be issued up to 9 hr in advance of the core collapse itself

Authors: Machado, LN; Abe, K; Hayato, Y; Hiraide, K; Ieki, K

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Astronomical Society
• Journal: The Astrophysical Journal
• Volume: 935
• Issue: 1
• Pages: 40-40
• Publication date: 2022-08-12
• DOI: 10.3847/1538-4357/ac7f9c
• EISSN: 1538-4357
• ISSN: 0004-637X
• Language: English
• Keywords: Solar neutrino; Supernova; Neutrino oscillation; Neutrino; Astronomy; Stars; Physics; Astrophysics; Neutrino detector; Super-Kamiokande; Nuclear physics