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arXiv · 0903.2057

The Relation Between Optical Extinction and Hydrogen Column Density in the Galaxy

Tolga Guver·Feryal Ozel
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Abstract

A linear relation between the hydrogen column density (N_H) and optical extinction (A_V) in the Galaxy has long been observed. A number of studies found differing results in the slope of this relation. Here, we utilize the data on 22 supernova remnants that have been observed with the latest generation X-ray observatories and for which optical extinction and/or reddening measurements have been performed and find N_H (cm^-2) = (2.21 \pm0.09) x10^{21} A_V (mag). We compare our result with the previous studies and assess any systematic uncertainties that may affect these results.

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Tolga Guver, Feryal Ozel. 2009-08-21. The Relation Between Optical Extinction and Hydrogen Column Density in the Galaxy. https://doi.org/10.1111/j.1365-2966.2009.15598.x

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