SN1987A and neutrino non-radiative decay

• Published in: Physics letters. B Vol. 847; p. 138252
• Main Authors: Iváñez-Ballesteros, Pilar, Volpe, Maria Cristina
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 10.12.2023; Elsevier
• Subjects: Core-collapse supernova neutrinos; Neutrino masses and mixings; Neutrino non-radiative decay; SN1987A; SN1987A; Neutrino non-radiative decay; Neutrino masses and mixings; Core-collapse supernova neutrinos
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/j.physletb.2023.138252

We investigate neutrino non-radiative two-body decay in vacuum, in relation to SN1987A. In a full 3ν decay framework, we perform a detailed likelihood analysis of the 24 neutrino events from SN1987A observed by Kamiokande-II, IMB, and Baksan. We consider both normal and inverted neutrino mass orderings, and the possibility of strongly hierarchical and quasi-degenerate neutrino mass patterns. The results of the likelihood analysis show that the sensitivity is too low to derive bounds in the case of normal mass ordering. On the contrary, in the case of inverted mass ordering we obtain the bound τ/m≥2.4×105 s/eV (1.2×105) s/eV at 68% (90%) CL on the lifetime-to-mass ratio of the mass eigenstates ν2 and ν1.