The Flavor Composition of Supernova Neutrinos
Abstract
We show that standard matter effects in the outer layers of core-collapse supernovae significantly constrain the flavor composition of the neutrino flux, even with the enormous uncertainties originating from self-induced flavor conversions in the supernova core. Assuming an arbitrary initial flavor composition emerging from the supernova core, we find that, for the normal mass ordering, the fraction of neutrinos with electron flavor reaching the Earth, denoted as $f_{\nu_e}$, is constrained to be less than $0.5$ for all energies throughout the emission phase, whereas, for inverted mass ordering, we anticipate neutrinos arriving in near flavor equipartition ($f_{\nu_e}\approx 1/3$). In case adiabaticity is violated in the region of standard matter effects (e. g. due to shock waves), the result is flavor equipartition for both mass orderings. These results could be tested by future observations and may provide valuable insights into the properties of neutrino fluxes emerging from the supernova core.
- Publication:
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arXiv e-prints
- Pub Date:
- March 2024
- DOI:
- arXiv:
- arXiv:2403.14762
- Bibcode:
- 2024arXiv240314762C
- Keywords:
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- High Energy Physics - Phenomenology;
- Astrophysics - High Energy Astrophysical Phenomena;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- 7 pages + references, 2 figures, improved version, appendix added