The problems of neutrino masses, matter-antimatter asymmetry, and dark matter could be successfully addressed by postulating right-handed neutrinos with Majorana masses below the electroweak scale. Many more simulations and multi-dimensional simulations are needed to fully probe the parameter space of the initial conditions. In all of these calculations the same number of neutrinos and antineutrinos change flavor, making the least abundant between them the limiting factor for post-saturation flavor change. Weak electron lepton number (ELN) crossings in these simulations produce both slow growth of the instability and little difference between the flavor abundances in the initial and final states. Finally, we vary the number density, flux magnitude, and flux direction of the neutrinos and antineutrinos and demonstrate that these factors modify both the growth rate and post-saturation neutrino flavor abundances. We demonstrate the growth of both axially symmetric and asymmetric modes whose wavelength and growth rate match predictions from linear stability analysis. We conduct one-dimensional three-flavor simulations of neutrino quantum kinetics to demonstrate the outcome of this instability in a few example cases. In this work we present particle-in-cell calculations which follow the evolution of all flavors of neutrinos and antineutrinos through saturation and kinematic decoherence. Neutrinos of different flavors interact with matter differently, and much recent work has suggested that fast flavor instabilities are likely ubiquitous in both systems, but the final flavor content after the instability saturates has not been well understood. Neutrinos drive core-collapse supernovae, launch outflows from neutron star merger accretion disks, and set the ratio of protons to neutrons in ejecta from both systems that generate heavy elements in the universe. Many more simulations and multidimensional simulations are needed to fully probe the parameter space of the initial conditions. In all of these calculations the same number of neutrinos and antineutrinos change flavor, making the least abundant between them the limiting factor for postsaturation flavor change. Weak electron lepton number crossings in these simulations produce both slow growth of the instability and little difference between the flavor abundances in the initial and final states. Finally, we vary the number density, flux magnitude, and flux direction of the neutrinos and antineutrinos and demonstrate that these factors modify both the growth rate and postsaturation neutrino flavor abundances. Neutrinos drive core-collapse supernovae, launch outflows from neutron star merger accretion disks, and set the ratio of protons to neutrons in ejecta from both systems that generate heavy elements in the Universe.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |