PIRSA:21030032

Physical processes in high energy systems: neutrino fast flavour conversion and efficient magnetic energy dissipation

Li, X. (2021). Physical processes in high energy systems: neutrino fast flavour conversion and efficient magnetic energy dissipation. Perimeter Institute. https://pirsa.org/21030032

Li, Xinyu. Physical processes in high energy systems: neutrino fast flavour conversion and efficient magnetic energy dissipation. Perimeter Institute, Mar. 18, 2021, https://pirsa.org/21030032 

          @misc{ pirsa_PIRSA:21030032,
            doi = {10.48660/21030032},
            url = {https://pirsa.org/21030032},
            author = {Li, Xinyu},
            keywords = {Strong Gravity},
            language = {en},
            title = {Physical processes in high energy systems: neutrino fast flavour conversion and efficient magnetic energy dissipation},
            publisher = {Perimeter Institute},
            year = {2021},
            month = {mar},
            note = {PIRSA:21030032 see, \url{https://pirsa.org}}
          }

Xinyu Li

Tsinghua University

Talk number
PIRSA:21030032
Collection
Talk Type
Subject
Abstract

The talk will be based on my latest two papers 2103.02616 and 2103.05700. 
In the first part, I will present my GRMHD simulation of a neutron-star post-merger disk with neutrino fast flavour conversion included dynamically. The fast conversion of neutrinos can lead to flavour space equipartition ubiquitously on the time scale as short as 1ns. Due to the reduction of the number density of electron and anti-electron neutrino, the ejecta becomes more neutron rich. The final r-process nucleosynthesis sees an enhanced abundance of heavy elements close to the solar values. A similar effect may allow for increased lanthanide production in collapsars.
In the second part, I will present fast magnetic energy dissipation through the collision of Alfven waves with anti-aligned magnetic fields. The collision produces a current sheet sustained by an electrical field breaking the MHD condition. Particles entering the current sheet are accelerated following a relativistic variation of Speiser orbit and escape with higher energy. This mechanism can dissipate a large fraction of wave energy, nearly 100% when the wave magnetic field equals the background magnetic field. The fast dissipation may occur in various objects, including magnetars, jets from accreting black holes, and pulsar wind nebulae.