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Getting the Red Out: A Stellar Approach to Determining Spatial Variations of Interstellar Dust

I. I. Ivans·C. Sneden·R. P. Kraft·N. B. Suntzeff·V. V. Smith·G. E. Langer·J. P. Fulbright
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Abstract

By employing two different spectroscopic techniques we have mapped out the variable ISM dust extinction endemic to globular cluster M4. We derive an average E(B-V) reddening of 0.33 +/- 0.01 and R = 3.4 +/- 0.4, both in good agreement with previous studies of M4. For individual stars in the most heavily reddened regions of M4, we find E(B-V) values significantly higher than those inferred by studies of interstellar gas; for heavily reddened regions, the gas measured in column density measurements may not completely trace the dust.

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I. I. Ivans, C. Sneden, R. P. Kraft, N. B. Suntzeff, V. V. Smith, G. E. Langer, J. P. Fulbright. 2000-05-31. Getting the Red Out: A Stellar Approach to Determining Spatial Variations of Interstellar Dust. https://arxiv.org/abs/astro-ph/0005595

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