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Horizontal branch morphology: A new photometric parametrization [PDF]
Astronomy & Astrophysics, 2019 Context. Theory and observations indicate that the distribution of stars along the horizontal branch of Galactic globular clusters mainly depends on the metal content. However, the existence of globular clusters with similar metal content and absolute age but different horizontal branch morphologies, suggests the presence of another parameter affecting
Marianna Torelli +13 more
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The horizontal branch of the Sculptor dwarf galaxy [PDF]
Astronomy & Astrophysics, 2013 We have performed the first detailed simulation of the horizontal branch of the Sculptor dwarf spheroidal galaxy by means of synthetic modelling techniques,taking consistently into account the star formation history and metallicity evolution as determined from the main sequence and red giant branch spectroscopic observations. The only free parameter in
Maurizio Salaris +4 more
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Multimodal Distributions along the Horizontal Branch [PDF]
The Astrophysical Journal, 1998 We report on HST/WFPC2 U,V and far-ultraviolet observations of two Galactic Globular Clusters (GGCs), NGC 6205 = M13 and NGC 6093 = M80. Both of these clusters have horizontal-branch (HB) tails that extend to the helium-burning main sequence, with the hottest stars reaching theoretical effective temperatures above 35,000 K.
F. R. Ferraro +4 more
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A new calibration for the Blue Horizontal Branch [PDF]
Monthly Notices of the Royal Astronomical Society, 2013 We suggest a simple analytic approximation for magnitudes and hence distances of Blue Horizontal Branch (BHB) stars in Sloan colours. Precedent formulations do not offer a simple closed formula, nor do they cover the full dependences, e.g. on metallicity.
Ralph Schönrich, Francesco Fermani
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Precision CCD Photometry of the Horizontal Branch [PDF]
Symposium - International Astronomical Union, 1995 The Strömgren four-color system is well suited to the measure and analysis of horizontal-branch stars. The increased accuracy of the CCD photometric system and the ability to measure fainter stars in very crowded regions make the combination of the CCD system and four-color photometry an excellent one to study horizontal-branch stars in globular ...
A. G. D. Philip
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Rotation of Horizontal‐Branch Stars in Globular Clusters [PDF]
The Astrophysical Journal, 2000 The rotation of horizontal branch stars places important constraints on angular momentum evolution in evolved stars and therefore rotational mixing on the giant branch. Prompted by new observations of rotation rates of horizontal branch stars, we calculate simple models for the angular momentum evolution of a globular cluster giant star from the base ...
Alison Sills, Marc H. Pinsonneault
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Horizontal Branch Stellar Evolution
, 1995 I review aspects of the evolution of horizontal branch (HB) stars. I start by discussing current topics in the study of HB stellar evolution, including a brief review of the main determinants of the structure of low-mass core helium burning stars and of HB morphology.
Ben Dorman
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Rotation, planets, and the 'second parameter' of the horizontal branch [PDF]
Monthly Notices of the Royal Astronomical Society, 2000 We analyze the angular momentum evolution from the red giant branch (RGB) to the horizontal branch (HB) and along the HB. Using rotation velocities for stars in the globular cluster M13, we find that the required angular momentum for the fast rotators is up to 1-3 orders of magnitude (depending on some assumptions) larger than that of the sun.
Noam Soker, Amos Harpaz
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Mass Loss on the Horizontal Branch: An Application to NGC 6791 [PDF]
The Astrophysical Journal, 2000 The presence of a substantial number of hot stars in the extremely metal-rich} open cluster NGC6791 has been a mystery. If these hot stars are in their core helium burning phase, they are significantly bluer (hotter) than predicted by canonical stellar evolution theory. No obvious explanation is available yet.
H. Yong, P. Demarque, Sukyoung K. Yi
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Horizontal branch evolution, metallicity, and sdB stars [PDF]
Astronomy & Astrophysics, 2011 Accepted for publication by A& ...
Jacques Richer +3 more
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