Results 231 to 240 of about 26,349 (244)

Horizontal-Branch Stars

2015
Most stars with \(M\stackrel{
Georges Michaud, Georges Alecian, Jacques Richer   +2 more
openaire   +1 more source

Current problems on horizontal branch stars

Astrophysics and Space Science, 1975
Expected characteristics of RR Lyrae stars as a function of the evolutive parameters are reported. Results from both evolutionary and pulsational investigations are collected in a suitable form, to show the general constraints to any interpretative analysis of the observations.
Filippina Caputo, Vittorio Castellani
openaire   +1 more source

Galactic Chemical Evolution: Insights From Field Horizontal Branch Stars

EAS Publications Series, 2015
In this study we conducted the first large-sample red horizontal branch field star survey in the Milky Way. We carried out a detailed high-resolution spectroscopic abundance analysis of the RHB candidates. We also derived 12 C /13 C isotopic ratios, important indicators of stellar evolution, by using the CN features mainly located around the 8004 A.
Afsar, M., Bocek, G., Sehitoglu, G., Sneden, C., Bozkurt, Z.   +4 more
openaire   +1 more source

Convective Overshooting in Horizontal Branch Stars

1987
The evolution of horizontal branch stars up to the starting of the thermally pulsing regime of the He-burning shell is investigated with the aid of a non local treatment of the core convection. The formalism follows the overshooting model by Bressan et al (1981) which opposes to the classical, local schemes for overshooting and semiconvection currently
C. Chiosi, G. Bertelli, A. Bressan
openaire   +1 more source

A-Type Horizontal-Branch Stars

1975
Horizontal-branch stars have attracted our attention as conspicuous examples of highly evolved population-II stars. Recent developments in the theoretical calculations of the internal structure of horizontal-branch stars (see Rood, 1970; Demarque and Mengel, 1971; Sweigart and Demarque, 1972) enable detailed studies on the evolutionary tracks ...
openaire   +1 more source

Current problems on horizontal-branch (HB) stars

Astrophysics and Space Science, 1980
The influence of Main Sequence stellar rotation on horizontal branch stars and on RR Lyrae pulsational properties is studied. Synthetic HB's are computed for a wide range of original chemical compositions taking into account evolutionary effects based on Fusi Pecci-Renzini's evolutionary scheme.
V. Castellani, G. Ponte, A. Tornamb�
openaire   +1 more source

Blue Horizontal Branch Stars in Pan-STARRS

EAS Publications Series, 2014
We discuss the selection of blue horizontal branch stars (BHBs) using preliminary Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) color data and outline techniques for structure detection using those data. We first outline the adaptation of an old color selection for for BHBs using Sloan Digital Sky Survey (SDSS) data to the Pan ...
Vickers, J. J., Huxor, A. P., Grebel, E. K.   +2 more
openaire   +2 more sources

Horizontal-Branch Stars with Strong He Lines

1988
We discuss observations of He lines at λ 4026 A in two stars in NGC 6752 and three in M 92. M 92 and NGC 6752 are moderate to extreme second parameter clusters. The presence of He lines in stars where diffusion should deplete atmospheric helium may be a clue to the identity of the second parameter.
Deborah A. Crocker, Robert T. Rood
openaire   +1 more source

Horizontal-branch Stars

2004
openaire   +1 more source

The Na-O anticorrelation in horizontal branch stars Corrigendum: II. NGC 1851

, 2012
R. Gratton, S. Lucatello, E. Carretta, A. Bragaglia, V. D’Orazi, Y. Momany, A. Sollima, M. Salaris, S. Cassisi   +8 more
semanticscholar   +1 more source