PT Journal
AU Abbar, S
   Capozzi, F
TI Suppression of fast neutrino flavor conversions occurring at large distances in core-collapse supernovae
SO Journal of Cosmology and Astroparticle Physics
JI J. Cosmol. Astropart. Phys.
PY 2022
BP 051
EP 13pp
VL 03
IS 3
DI 10.1088/1475-7516/2022/03/051
LA English
DE supernova neutrinos; core-collapse supernovae; neutrino astronomy; supernovas
AB Neutrinos propagating in dense neutrino media such as core-collapse supernovae and neutron star merger remnants can experience the so-called fast flavor conversions on scales much shorter than those expected in vacuum. A very generic class of fast flavor instabilities is the ones which are produced by the backward scattering of neutrinos off the nuclei at relatively large distances from the supernova core. In this study we demonstrate that despite their ubiquity, such fast instabilities are unlikely to cause significant flavor conversions if the population of neutrinos in the backward direction is not large enough. Indeed, the scattering-induced instabilities can mostly impact the neutrinos traveling in the backward direction, which represent only a small fraction of neutrinos at large radii. We show that this can be explained by the shape of the unstable flavor eigenstates, which can be extremely peaked at the backward angles.
ER