Ultraviolet Interstellar Extinction toward High Galactic Latitudes

Abstract

Nearby high Galactic latitude clouds provide a unique laboratory to study the physics and structure of the Galactic interstellar medium (ISM) and the properties of the interstellar dust. In this work, we select 32 sightlines toward reddened background stars at high Galactic latitudes with |b| > 20 degr, for which high-quality spectra from the International Ultraviolet Explorer are available. We utilize the "pair-method" to derive the ultraviolet interstellar extinction curves for these sightlines. We examine the extinction properties of these sightlines and find no systematic variations with the Galactic latitudes, although they do show appreciable sightline-to-sightline variations.