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arXiv · 1307.3798

Diffuse interstellar bands as probes of small-scale interstellar structure

Keith T. Smith·Martin A. Cordiner·Peter J. Sarre
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Abstract

We present observations which probe the small-scale structure of the interstellar medium using diffuse interstellar bands (DIBs). Towards HD 168075/6 in the Eagle Nebula, significant differences in DIB absorption are found between the two lines of sight, which are separated by 0.25 pc, and {\lambda}5797 exhibits a velocity shift. Similar data are presented for four stars in the {\mu} Sgr system. We also present a search for variations in DIB absorption towards {\kappa} Vel, where the atomic lines are known to vary on scales of ~10 AU. Observations separated by ~9 yr yielded no evidence for changes in DIB absorption strength over this scale, but do reveal an unusual DIB spectrum.

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Keith T. Smith, Martin A. Cordiner, Peter J. Sarre. 2013-07-14. Diffuse interstellar bands as probes of small-scale interstellar structure. https://doi.org/10.1017/s1743921313015779

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