Effect of hyperon-hyperon interaction on bulk viscosity and r-mode instability in neutron stars
Abstract
We investigate the effect of hyperon matter including hyperon-hyperon interaction on bulk viscosity. Equations of state are constructed within the framework of a relativistic field theoretical model where baryon-baryon interaction is mediated by the exchange of scalar and vector mesons. Hyperon-hyperon interaction is also taken into account by the exchange of two strange mesons. This interaction results in a smaller maximum mass neutron star compared with the case without the interaction. The coefficient of bulk viscosity due to the non-leptonic weak process is determined by these equations of state. The interacting hyperon matter reduces the bulk viscosity coefficient in a neutron star interior compared with the no interaction case. The r-mode instability is more effectively suppressed in hyperon-hyperon interaction case than that without the interaction.
Keywords
Cite
@article{arxiv.astro-ph/0602538,
title = {Effect of hyperon-hyperon interaction on bulk viscosity and r-mode instability in neutron stars},
author = {Debarati Chatterjee and Debades Bandyopadhyay},
journal= {arXiv preprint arXiv:astro-ph/0602538},
year = {2009}
}
Comments
25 pages, 10 figures; two new figures added and results and discussion section revised; final version to appear in PRD