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arXiv · 1306.6506

The Galactic NH - AV Relation and its Application to Historical Galactic SNRs

Wen-Wu Tian·Hongquan Su·F. Y. Xiang
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Abstract

We refine a classic relation between the hydrogen column density (NH) and optical extinction (Av) by employing 39 Galactic Supernova Remnants (SNRs) with X-rays, optical and/or infra-red data available. We find NH = (1.69+/-0.07)*10^21 Av cm^(-2) mag^(-1) . Applying this relation to three Galactic SNRs with good historical records allows us to further constrain either their progenitor's distances or magnitudes, which is independent access to their distances.

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Wen-Wu Tian, Hongquan Su, F. Y. Xiang. 2013-06-27. The Galactic NH - AV Relation and its Application to Historical Galactic SNRs. https://arxiv.org/abs/1306.6506

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