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arXiv · 0708.0599

A New Mechanism for Polarizing Light from Obscured Stars

J. R. Kuhn·S. V. Berdyugina·D. M. Fluri·D. M. Harrington·J. O. Stenflo
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Abstract

Recent spectropolarimetric observations of Herbig AeBe stellar systems show linear polarization variability with wavelength and epoch near their obscured H-alpha emission. Surprisingly, this polarization is not coincident with the H-alpha emission peak but is variable near the absorptive part of the line profile. With a new and novel model we show here that this is evidence of optical pumping - anisotropy of the incident radiation that leads to a linear polarization-dependent optical depth within the intervening hydrogen wind or disk cloud. This effect can yield a larger polarization signal than scattering polarization in these systems.

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J. R. Kuhn, S. V. Berdyugina, D. M. Fluri, D. M. Harrington, J. O. Stenflo. 2007-08-04. A New Mechanism for Polarizing Light from Obscured Stars. https://doi.org/10.1086/522425

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