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A New Mechanism for Polarizing Light from Obscured Stars

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 نشر من قبل David Harrington
 تاريخ النشر 2007
  مجال البحث فيزياء
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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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