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arXiv · 0704.1598

Radiative transitions of the helium atom in highly magnetized neutron star atmospheres

Zach Medin·Dong Lai·Alexander Y. Potekhin
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Abstract

Recent observations of thermally emitting isolated neutron stars revealed spectral features that could be interpreted as radiative transitions of He in a magnetized neutron star atmosphere. We present Hartree-Fock calculations of the polarization-dependent photoionization cross sections of the He atom in strong magnetic fields ranging from 10^12 G to 10^14 G. Convenient fitting formulae for the cross sections are given as well as related oscillator strengths for various bound-bound transitions. The effects of finite nucleus mass on the radiative absorption cross sections are examined using perturbation theory.

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Zach Medin, Dong Lai, Alexander Y. Potekhin. 2008-01-18. Radiative transitions of the helium atom in highly magnetized neutron star atmospheres. https://doi.org/10.1111/j.1365-2966.2007.12518.x

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