Dust-Scattered Ultraviolet Halos around Bright Stars

Abstract

We have discovered ultraviolet halos extending as far as 5° around four (of six) bright UV stars using data from the GALEX satellite. These halos are due to the scattering of the starlight from nearby thin, foreground dust clouds. We have placed limits of 0.58 $\pm$ 0.12 and 0.72 $\pm$ 0.06 on the phase function asymmetry factor (g) and limits on the albedo of 0.10 $\pm$ 0.05 and 0.26 $\pm$ 0.10 in the FUV (1521 Å) and NUV (2320 Å) bands, respectively. We suggest that these halos are a common feature around bright stars and may be used to explore the scattering function of interstellar grains at small angles.

Accepted Astrophysical Journal; 19 pages; 7 figures; online data

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Cited by in corpus (9)

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• GALEX Diffuse Observations of the Sky: The Data
• The Mystery of the Cosmic Diffuse Ultraviolet Background Radiation
• The Diffuse Galactic Far-Ultraviolet Sky
• The Pseudo-zodi Problem for Edge-on Planetary Systems
• Modelling Dust Scattering in our Galaxy
• Far-Ultraviolet Observations of the Spica Nebula and the Interaction Zone
• Evidence for large-scale excesses associated with low HI column densities in the sky I. Dust excess
• Dust properties from GALEX observations of a UV halo around Spica