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Related papers: A Main Sequence CH-star in the globular cluster M5…

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We present a spectral atlas of the post-main-sequence population of the most massive Galactic globular cluster, omega Centauri. Spectra were obtained of more than 1500 stars selected as uniformly as possible from across the (B, B-V)…

We present an analysis of a large sample of moderate resolution Keck LRIS spectra of subgiants and stars at the base of the RGB in M15, most within the range 16.5 < V < 19.5 (1.2 < M_V < 4.2), with the goal of deriving C abundances (from…

Astrophysics · Physics 2008-11-26 Judith G. Cohen , Michael M. Briley , Peter B. Stetson

We have derived CNO abundances in 12 RR Lyrae stars. Four stars show [C/Fe] near 0.0 and two stars show [C/Fe] = 0.52 and 0.65. Red giant branch stars, which are known to be the predecessors of RR Lyrae stars, generally show a deficiency of…

Solar and Stellar Astrophysics · Physics 2009-11-13 George Wallerstein , V. V. Kovtyukh , S. M. Andrievsky

We present abundances of C, N, O, F, Na, and Fe in six giant stars of the tidally disrupted globular cluster NGC 6712. The abundances were derived by comparing synthetic spectra with high resolution infrared spectra obtained with the…

Wide-field $u'g'r'i'z'$ Dark Energy Camera observations centred on the giant elliptical galaxy NGC5128 covering $\sim21deg^2$ are used to compile a new catalogue of $\sim3200$ globular clusters (GCs). We report 2404 new candidates,…

Well determined radial velocities and abundances are essential for analyzing the properties of the Globular Cluster system of the Milky Way. However more than 50% of these clusters have no spectroscopic measure of their metallicity. In this…

This paper reports a Galactic kinematical and dynamical analysis of 1003 main-sequence carbon stars. The sample is drawn from the Sloan Digital Sky Survey, and cross-matched with Gaia DR3 to obtain 6-dimensional positions and velocities…

Solar and Stellar Astrophysics · Physics 2025-09-09 Jay Farihi , Jason L. Sanders , Sophia Lilleengen , Lewis J. Whitehouse , Denis Erkal

Enhancement and spread of helium among globular cluster stars have been recently suggested as a way to explain the horizontal branch blue tails, in those clusters which show a primordial spread in the abundances of CNO and other elements…

Astrophysics · Physics 2008-11-26 Francesca D'Antona , Vittoria Caloi

We analyse a Chandra observation of the rich globular cluster NGC 362, finding 33 X-ray sources within 1' (1.2 half-mass radii) of the cluster center. Spectral analysis of the brightest source (X1) shows blackbody-like emission, indicating…

High Energy Astrophysical Phenomena · Physics 2024-03-26 Gourav Kumawat , Craig O. Heinke , Haldan N. Cohn , Phyllis M. Lugger

We present an analysis of a large sample of moderate resolution Keck LRIS spectra of subgiant (V \sim 17.2) and fainter stars in the Galactic globular cluster M5 (NGC 5904) with the goal of deriving C and N abundances. Star-to-star…

Astrophysics · Physics 2009-11-07 Judith G. Cohen , Michael M. Briley , Peter B. Stetson

We obtained FLAMES GIRAFFE+UVES spectra for both first and second-generation red giant branch (RGB) stars in the globular cluster (GC) NGC 362 and used them to derive abundances of 21 atomic species for a sample of 92 stars. The surveyed…

Astrophysics of Galaxies · Physics 2015-06-16 E. Carretta , A. Bragaglia , R. G. Gratton , S. Lucatello , V. D'Orazi , M. Bellazzini , G. Catanzaro , F. Leone , Y. Momany , A. Sollima

We have determined stellar parameters and abundances for 221 giant branch stars in the globular cluster {\omega} Centauri. A combination of photometry and lower-resolution spectroscopy was used to determine temperature, gravity,…

Solar and Stellar Astrophysics · Physics 2015-06-11 Jeffrey D. Simpson , P. L. Cottrell , C. C. Worley

We present V,I deep CCD photometry for three fields of the dwarf galaxy in Sagittarius (Sgr). One of the fields is centered on the globular cluster NGC 6715 (M54), which lies in one of the dense clumps of the Sgr galaxy. Comparing the CMD…

Astrophysics · Physics 2007-05-23 G. Marconi , R. Buonanno , M. Castellani , G. Iannicola , L. Pasquini , P. Molaro , L. Pulone

Binaries in the cores of globular clusters are known to prevent the gravitational collapse of the cluster, and simulations predict that the core of NGC 6397 contains a large number of white dwarfs (WDs), of which many are expected to be…

Solar and Stellar Astrophysics · Physics 2026-03-18 Fabian Göttgens , Marilyn Latour , Ulrich Heber , Sebastian Kamann , Kyle Kremer , Sven Martens , Stefan Dreizler

There is increasing evidence that some massive globular clusters (GCs) host multiple stellar populations having different heavy element abundances enriched by supernovae. They usually accompany multiple red giant branches (RGBs) in the…

Astrophysics of Galaxies · Physics 2015-06-12 Seok-Joo Joo , Young-Wook Lee

Dwarf carbon stars are dominated by members of the Galactic halo and are thus likely carbon-enhanced metal-poor stars. In this work, a sample of 879 bona fide dwarf carbon stars are characterized by their ground-based light curves, and p<15…

Solar and Stellar Astrophysics · Physics 2026-05-13 Jonathan A. G. McLennan , Jay Farihi , Steven G. Parsons

Stromgren indices v and b are combined with broad-band index I, and a new index p, the short wavelength half of the v band, to estimate CN 4215A molecular absorption in a sample of stars in M22. The results have been used to estimate carbon…

Astrophysics · Physics 2007-05-23 David Peat , Raymond Butler

High resolution spectra of 123 red giant stars in the globular cluster M13 and 64 red giant stars in M92 were obtained with Hectochelle at the MMT telescope. Emission and line asymmetries in Halpha, and Ca K are identified, characterizing…

Solar and Stellar Astrophysics · Physics 2009-11-13 Sz. Mészáros , A. K. Dupree , T. Szalai

It has been suggested that giant planet occurrence peaks for stars with $M_{\ast}~\approx~3~M_{\odot}$ at a value a factor of 4 higher than observed for solar-mass stars. This population of giant planets predicted to frequently orbit…

Earth and Planetary Astrophysics · Physics 2025-07-02 Sihao Cheng , Kevin C. Schlaufman , Ilaria Caiazzo

We present a detailed chemical composition analysis of 35 red giant stars in the globular cluster M22. High resolution spectra for this study were obtained at five observatories, and analyzed in a uniform manner. We have determined…