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arXiv · 2509.26418

Dynamical equilibria of fast neutrino flavor conversion

Jiabao Liu·Lucas Johns·Hiroki Nagakura·Masamichi Zaizen·Shoichi Yamada
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Abstract

Dense neutrino systems, which display collectivity mediated by the weak interaction, have deep parallels with mean-field kinetic systems governed by other fundamental forces. We identify analogues in fast flavor conversion (FFC) of some time-honored nonlinear phenomena in plasmas and self-gravitating systems. We focus in particular on nonlinear Landau damping and collisionless equilibria, which are likely important pieces of the unsolved puzzle of neutrino oscillations in core-collapse supernovae and neutron star mergers. Our analysis additionally reveals the previously unexplored phenomenon of flavor-wave synchronization.

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Jiabao Liu, Lucas Johns, Hiroki Nagakura, Masamichi Zaizen, Shoichi Yamada. 2025-09-30. Dynamical equilibria of fast neutrino flavor conversion. https://arxiv.org/abs/2509.26418

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