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Bulk viscosity in kaon condensed matter

Debarati Chatterjee·Debades Bandyopadhyay
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Abstract

We investigate the effect of $K^-$ condensed matter on bulk viscosity and r-mode instability in neutron stars. The bulk viscosity coefficient due to the non-leptonic process $n \rightleftharpoons p + K^-$ is studied here. In this connection, equations of state are constructed within the framework of relativistic field theoretical models where nucleon-nucleon and kaon-nucleon interactions are mediated by the exchange of scalar and vector mesons. We find that the bulk viscosity coefficient due to the non-leptonic weak process in the condensate is suppressed by several orders of magnitude. Consequently, kaon bulk viscosity may not damp the r-mode instability in neutron stars.

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Debarati Chatterjee, Debades Bandyopadhyay. 2007-05-30. Bulk viscosity in kaon condensed matter. https://doi.org/10.1103/physrevd.75.123006

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