Ultraviolet radiation from evolved stellar populations. 2: The ultraviolet upturn phenomenon in elliptical galaxies
- 1 March 1995
- journal article
- Published by American Astronomical Society in The Astrophysical Journal
- Vol. 442, 105-141
- https://doi.org/10.1086/175428
Abstract
We present an analysis of the far-ultraviolet upturn phenomenon (UVX) observed in elliptical galaxies and spiral galaxy bulges. Our premise is that the UV radiation from these systems emanates primarily from extreme horizontal branch (EHB) stars and their progeny. We re-derive the broad-band UV colors $1500-V$ and $2500-V$ for globular clusters and elliptical galaxies from the available satellite data and investigate color-color and color-line strength correlations. We also provide the ingredients necessary for constructing models with arbitrary HB morphologies.Comment: uuencoded compressed postscript file, 60pp. (revisions on pp. 7,8,22,33,37 & 57