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arXiv · 0906.3134

Pion mass effects on axion emission from neutron stars through NN bremsstrahlung processes

S. Stoica·B. Pastrav·J. E. Horvath·M. P. Allen
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Abstract

The rates of axion emission by nucleon-nucleon bremsstrahlung are calculated with the inclusion of the full momentum contribution from a nuclear one pion exchange (OPE) potential. The contributions of the neutron-neutron (nn), proton-proton (pp) and neutron-proton (np) processes in both the nondegenerate and degenerate limits are explicitly given. We find that the finite momentum corrections to the emissivities are quantitatively significant for the non-degenerate regime and temperature-dependent, and should affect the existing axion mass bounds. The trend of these nuclear effects is to diminish the emissivities.

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S. Stoica, B. Pastrav, J. E. Horvath, M. P. Allen. 2009-11-30. Pion mass effects on axion emission from neutron stars through NN bremsstrahlung processes. https://doi.org/10.1016/j.nuclphysa.2009.07.007%2010.1016%2Fj.nuclphysa.2009.12.001

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