1998/02/28 by Dong Lai, Yongzhong Qian, Y. -Z. Qian · 109 citations
Physics and Astronomy · #Astrophysics #Astrophysics and Cosmic Phenomena #Landau quantization #Magnetic field #Neutrino #Neutrino Physics Research #Neutron #Neutron star #Nuclear physics #Physics #Pulsar #Pulsars and Gravitational Waves Research #Quantum mechanics #astro-ph
paper · pdf · doi:10.1086/306203
published in The Astrophysical Journal 505(2), 844-853 (IOP Publishing) · AASTeX, 25 pages. Expanded introduction and references. This revised version was accepted by ApJ in April 1998 (to appear in the Oct 1 issue)
arxiv created 1998/06/21 · openalex publication_date 1998/10/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/08
In proto-neutron stars with strong magnetic fields, the cross section for ν e ( e ) absorption on neutrons (protons) depends on the local magnetic field strength resulting from the quantization of energy levels for the e - ( e + ) produced in the final state. If the neutron star possesses an asymmetric magnetic field topology in the sense that the magnitude of magnetic field in the north pole is different from that in the south pole, then asymmetric neutrino emission may be generated. We calculate the absorption cross sections of ν e and e in strong magnetic fields as a function of the neutrino energy. These cross sections exhibit oscillatory behaviors that occur because new Landau levels for the e - ( e + ) become accessible as the neutrino energy increases. By evaluating the appropriately averaged neutrino opacities, we demonstrate that the change in the local neutrino flux caused by the modified opacities is rather small. To generate appreciable kick velocity (~300 km s -1 ) to the newly formed neutron star, the difference between the field strengths at the two opposite poles of the star must be at least 10 16 G. We also consider the magnetic field effect on the spectral neutrino energy fluxes. The oscillatory features in the absorption opacities give rise to modulations in the emergent spectra of ν e and e .