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Equation of state and opacities for hydrogen atmospheres of magnetars

A. Y. Potekhin·G. Chabrier
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Abstract

The equation of state and radiative opacities of partially ionized, strongly magnetized hydrogen plasmas, presented in a previous paper [ApJ 585, 955 (2003), astro-ph/0212062] for the magnetic field strengths 8.e11 G < B < 3.e13 G, are extended to the field strengths 3.e13 G < B < 1.e15 G, relevant for magnetars. The first- and second-order thermodynamic functions and radiative opacities are calculated and tabulated for 5.e5 < T < 4.e7 K in a wide range of densities. We show that bound-free transitions give an important contribution to the opacities in the considered range of B in the outer neutron-star atmosphere layers. Unlike the case of weaker fields, bound-bound transitions are unimportant.

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A. Y. Potekhin, G. Chabrier. 2003-09-11. Equation of state and opacities for hydrogen atmospheres of magnetars. https://doi.org/10.1086/379807

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