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Horizontal branch stars: the interplay between observations and theory, and insights into the formation of the Galaxy
(2009)
We review and discuss horizontal branch (HB) stars in a broad astrophysical context, including both variable and non-variable stars. A reassessment of the Oosterhoff dichotomy is presented, which provides unprecedented ...
The peculiar properties of horizontal-branch stars in ω Centauri
(2011)
We measured temperatures, gravities, and masses for a large sample of blue horizontal branch stars in omega Centauri, comparing the results with theoretical expectations for canonical and He-enriched stars, and with previous ...
The ages of stars: The horizontal branch
(2009)
Horizontal branch (HB) stars play a particularly important role in the “age debate,” since they are at the very center of the long-standing “second parameter” problem. In this review, I discuss some recent progress in our ...
Near-Field Cosmology with Horizontal Branch and RR Lyrae Stars
(2006)
The importance of horizontal branch and RR Lyrae stars is discussed in the context of cosmological arguments for the formation of the Galactic halo and its satellite dwarf galaxies. It is shown, in particular, that the ...
A Hot Horizontal Branch Star With A Close K-Type Main-Sequence Companion
(2015)
Dynamical interactions in binary systems are thought to play a major role in the formation of extreme horizontal branch stars (EHBs) in the Galactic field. However, it is still unclear if the same mechanisms are at work ...
The peculiar properties of horizontal-branch stars in ω Centauri
(2011)
We measured temperatures, gravities, and masses for a large sample of blue horizontal branch stars in omega Centauri, comparing the results with theoretical expectations for canonical and He-enriched stars, and with previous ...
A catalog of rotational and radial velocities for evolved stars - IV. Metal-poor stars
(EDP SCIENCES S A, 2006-11)
Aims. The present paper describes the first results of an observational program intended to refine and extend the existing v sin i measurements of metal-poor stars, with an emphasis on field evolved stars.
Methods. The ...
Horizontal Branch Stars and the Ultraviolet Universe
(2009)
Extremely hot horizontal branch (HB) stars and their progeny are widely considered to be responsible for the ``ultraviolet upturn'' (or UVX) phenomenon observed in elliptical galaxies and the bulges of spirals. Yet, the ...