Astronomy and Astrophysics – Astrophysics
Scientific paper
2004-09-13
Phys.Rev. C70 (2004) 065806
Astronomy and Astrophysics
Astrophysics
17 pages, 23 included ps figures
Scientific paper
10.1103/PhysRevC.70.065806
Nonuniform neutron-rich matter present in both core-collapse supernovae and neutron-star crusts is described in terms of a semiclassical model that reproduces nuclear-matter properties and includes long-range Coulomb interactions. The neutron-neutron correlation function and the corresponding static structure factor are calculated from molecular dynamics simulations involving 40,000 to 100,000 nucleons. The static structure factor describes coherent neutrino scattering which is expected to dominate the neutrino opacity. At low momentum transfers the static structure factor is found to be small because of ion screening. In contrast, at intermediate momentum transfers the static structure factor displays a large peak due to coherent scattering from all the neutrons in a cluster. This peak moves to higher momentum transfers and decreases in amplitude as the density increases. A large static structure factor at zero momentum transfer, indicative of large density fluctuations during a first-order phase transition, may increase the neutrino opacity. However, no evidence of such an increase has been found. Therefore, it is unlikely that the system undergoes a simple first-order phase transition. It is found that corrections to the commonly used single heavy nucleus approximation first appear at a density of the order of $10^{13}$ g/cm$^3$ and increase rapidly with increasing density. Thus, neutrino opacities are overestimated in the single heavy nucleus approximation relative to the complete molecular dynamics simulations.
Berry Donald K.
Carriere Josef
Horowitz Charles J.
Perez-Garcia Angeles M.
Piekarewicz Jorge
No associations
LandOfFree
Nonuniform Neutron-Rich Matter and Coherent Neutrino Scattering does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Nonuniform Neutron-Rich Matter and Coherent Neutrino Scattering, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Nonuniform Neutron-Rich Matter and Coherent Neutrino Scattering will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-530296