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arXiv · 0705.4133

Scattering polarization of hydrogen lines from electric-induced atomic alignment

R. Casini·R. Manso Sainz
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Abstract

We consider a gas of hydrogen atoms illuminated by a broadband, unpolarized radiation with zero anisotropy. In the absence of external fields, the atomic J-levels are thus isotropically populated. While this condition persists in the presence of a magnetic field, we show instead that electric fields can induce the alignment of those levels. We also show that this electric alignment cannot occur in a two-term model of hydrogen (e.g., if only the Ly-alpha transition is excited), or if the level populations are distributed according to Boltzmann's law.

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R. Casini, R. Manso Sainz. 2008-03-11. Scattering polarization of hydrogen lines from electric-induced atomic alignment. https://doi.org/10.1088/0953-4075/41/8/085702

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