Dynamical response of the nuclear 'pasta' in neutron star crusts

Journal Article · Thu Sep 01 04:00:00 EDT 2005 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PhysRevC.72.035801· OSTI ID:20699016

Horowitz, C J; Perez-Garcia, M A; Berry, D K; Piekarewicz, J ^[1]

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1. Nuclear Theory Center and Department of Physics, Indiana University, Bloomington, Indiana 47405 (United States)

The nuclear pasta - a novel state of matter having nucleons arranged in a variety of complex shapes - is expected to be found in the crust of neutron stars and in core-collapse supernovae at subnuclear densities of about 10{sup 14} g/cm{sup 3}. Owing to frustration, a phenomenon that emerges from the competition between short-range nuclear attraction and long-range Coulomb repulsion, the nuclear pasta displays a preponderance of unique low-energy excitations. These excitations could have a strong impact on many transport properties, such as neutrino propagation through stellar environments. The excitation spectrum of the nuclear pasta is computed via a molecular-dynamics simulation involving up to 100,000 nucleons. The dynamic response of the pasta displays a classical plasma oscillation in the 1- to 2-MeV region. In addition, substantial strength is found at low energies. Yet this low-energy strength is missing from a simple ion model containing a single-representative heavy nucleus. The low-energy strength observed in the dynamic response of the pasta is likely to be a density wave involving the internal degrees of freedom of the clusters.

• OSTI ID: 20699016
• Journal Information: Physical Review. C, Nuclear Physics, Journal Name: Physical Review. C, Nuclear Physics Journal Issue: 3 Vol. 72; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
COMPUTERIZED SIMULATION
COULOMB FIELD
DEGREES OF FREEDOM
EXCITATION
HEAVY NUCLEI
MEV RANGE
MOLECULAR DYNAMICS METHOD
NEUTRINOS
NEUTRON STARS
NUCLEAR MATTER
NUCLEONS
PLASMA WAVES
SUPERNOVAE