Results 41 to 50 of about 189,331 (177)
Red-giant branch stellar cores as macroscopic dark matter detectors
Physical Review D, 2022 We show that macroscopic dark matter (DM) impacts on the degenerate helium cores of red-giant branch (RGB) stars can ignite helium fusion via DM-baryon elastic scattering. The onset of helium burning leads to a characteristic drop in luminosity and rise in temperature that marks the transition to a horizontal branch star.
Christopher Dessert, Zachary Johnson
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Red Clump stars in Kepler open cluster NGC 6819
EPJ Web of Conferences, 2015 We measure the large frequency separation, Δν, and the frequency of maximum amplitude, νmax, for 10 Red Clump (RC) single member (SM) stars in the Kepler open cluster NGC 6819. We derive luminosities and masses for each individual RC star.
Abedigamba O.P. +2 more
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CHEMICAL COMPOSITION OF ATMOSPHERES OF COOL GIANT STARS
Odessa Astronomical Publications, 2017 Results of determination of abundances of chemical elements in the atmospheres of 57 giant stars of the oxygen sequence of the Galactic disk axe given.
N. S. Komarov
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Calibration of the Tip of the Red Giant Branch
The Astrophysical Journal, 2020 Abstract The tip of the red giant branch (TRGB) method provides one of the most accurate and precise means of measuring the distances to nearby galaxies. Here we present a multi-wavelength, VIJHK absolute calibration of the TRGB based on observations of TRGB stars in the Large Magellanic Cloud (LMC), grounded on a geometric distance ...
Wendy L. Freedman +8 more
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Galactic calibration of the tip of the red giant branch [PDF]
Publications of the Astronomical Society of Australia, 2019 AbstractIndications from Gaia data release 2 are that the tip of the red giant branch (a population II standard candle related to the helium flash in low mass stars) is close to –4 in absolute I magnitude in the Cousins photometric system. Our sample is high-latitude southern stars from the thick disk and inner halo, and our result is consistent with ...
Mould, Jeremy +2 more
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, 2003 We present a comparison between theoretical models and the observed magnitude difference between the horizontal branch and the red giant branch bump for a sample of 53 clusters. We find a general agreement, though some discrepancy is still present at the two extremes of the metallicity range of globular clusters.
RIELLO M. +4 more
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CHEMICAL INHOMOGENEITY IN RED GIANT BRANCH STARS AND RR LYRAE VARIABLES IN NGC 1851: TWO SUBPOPULATIONS IN RED GIANT BRANCH [PDF]
The Astrophysical Journal, 2009 We investigate the red giant branch (RGB) subpopulations of NGC 1851 using Ca uvby photometry. Our color-magnitude diagrams show that the RGB stars have two subpopulations and the RGB stars in NGC 1851 appear to have distinct elemental abundance patterns with the [Ca/H] abundance. We discuss that the elemental abundance patterns can be explained by the
Lee, Jae-Woo +7 more
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Radial pulsations of red giant branch stars [PDF]
Astronomy Letters, 2017 We performed hydrodynamic computations of nonlinear stellar pulsations of population I stars at the evolutionary stages of the ascending red giant branch and the following luminosity drop due to the core helium flash. Red giants populating this region of the Hertzsprung--Russel diagram were found to be the fundamental mode pulsators.
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Dynamical Substructures of Galactic Globular Clusters III. NGC 7006 [PDF]
Journal of Astronomy and Space Sciences, 2005 To study the effects of giant population on dynamical substructures of the central region of NGC 7006, we examine the radial variations of ellipticity and position angle on BV stellar photometry using ellipse fitting technique.
Jonghwan Rhee, Young-Jong Sohn
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An empirical mass-loss law for Population II giants from the Spitzer-IRAC survey of Galactic globular clusters [PDF]
, 2014 The main aim of the present work is to derive an empirical mass-loss (ML) law for Population II stars in first and second ascent red giant branches.
Dalessandro, E. +6 more
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