Results 11 to 20 of about 498,367 (290)
On constructing horizontal branch models [PDF]
Astronomy & Astrophysics, 2005 We investigate different methods used to construct (zero-age) horizontal branch models and compare the resulting horizontal branch evolution with that of models resulting from the calculation of the complete stellar evolution from the main sequence and through the core helium flash.
Serenelli, A., Weiss, A.
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The horizontal-branch A stars [PDF]
Publications of the Astronomical Society of the Pacific, 1979 The observational determination of astrophysical parameters of horizontal-branch A stars is discussed. Effective temperatures, surface gravities, and bolometric magnitudes are determined for seven field horizontal-branch A stars, and their masses are calculated. The mean mass for these seven stars is 0.6 + or - 0.4 solar mass.
D. S. Hayes, A. G. D. Philip
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Blue Stragglers After the Main Sequence [PDF]
, 2008 We study the post-main sequence evolution of products of collisions between main sequence stars (blue stragglers), with particular interest paid to the horizontal branch and asymptotic giant branch phases.
Alison Sills +22 more
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Horizontal Branch A- and B-type Stars in Globular Clusters [PDF]
, 2004 Globular clusters offer ideal laboratories to test the predictions of stellar evolution. When doing so with spectroscopic analyses during the 1990s, however, the parameters we derived for hot horizontal branch stars deviated systematically from ...
Moehler, S.
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Non-variable horizontal-branch stars [PDF]
Symposium - International Astronomical Union, 1997 For 25 years our ignorance of the physical basis of this mass loss process has been the barrier to progress in understanding horizontal branch morphology. I review some recent observational and theoretical results which may be giving us clues about the nature of the mass loss process.
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Na-O anticorrelation and horizontal branches [PDF]
Astronomy & Astrophysics, 2007 We are studying the Na-O anticorrelation in several globular clusters of different Horizontal Branch (HB) morphology in order to derive a possible relation between (primordial) chemical inhomogeneities and morphological parameters of the cluster population.
E. Carretta +4 more
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Can Planets Influence the Horizontal Branch Morphology? [PDF]
, 1998 As stars which have planetary systems evolve along the red giant branch and expand, they interact with the close planets. The planets deposit angular momentum and energy into the red giant stars' envelopes, both of which are likely to enhance mass loss ...
Balbus A. S. +8 more
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Discovery of Blue Hook Stars in the Massive Globular Cluster M54
, 2003 We present BV photometry centered on the globular cluster M54 (NGC 6715). The color-magnitude diagram clearly shows a blue horizontal branch extending anomalously beyond the zero age horizontal branch theoretical models.
Alejandra Recio‐Blanco +7 more
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RR Lyrae variables in Galactic globular clusters: IV. Synthetic HB and RR Lyrae predictions
, 2004 We present theoretical predictions concerning horizontal branch stars in globular clusters, including RR Lyrae variables, as derived from synthetic procedures collating evolutionary and pulsational constraints.
Alexander +44 more
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Effects of tidally enhanced stellar wind on the horizontal branch morphology of globular clusters
, 2012 Metallicity is the first parameter to influence the horizontal branch (HB) morphology of globular clusters (GCs). It has been found, however, that some other parameters may also play an important role in affecting the morphology.
Chen, Xue-Fei +3 more
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