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Related papers: Magnesium Isotopes in Halo Stars

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We derive homogeneous abundances of Fe, O, Na and alpha-elements from high resolution FLAMES spectra for 76 red giant stars in NGC 6715 (M 54) and for 25 red giants in the surrounding nucleus of the Sagittarius (Sgr) dwarf galaxy. Our main…

Astrophysics of Galaxies · Physics 2015-05-18 E. Carretta , A. Bragaglia , R. G. Gratton , S. Lucatello , M. Bellazzini , G. Catanzaro , F. Leone , Y. Momany , G. Piotto , V. D'Orazi

Differential abundances of C, O, Mg, Al, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, Y, and Zr were determined from high signal-to-noise VLT/UVES spectra for 25 turnoff stars with -2.4 < [Fe/H] < -1.3. Effective temperatures were obtained from…

Astrophysics of Galaxies · Physics 2026-05-01 Poul Erik Nissen , Anish Amarsi

We report the first abundance analysis of 14 M giant stars in the Galactic bulge, based on R=25,000 infrared spectroscopy (1.5-1.8um) using NIRSPEC at the Keck II telescope. Because some of the bulge M giants reach high luminosities and…

Astrophysics · Physics 2009-11-11 R. Michael Rich , Livia Origlia

We present a chemical abundance study of three inner old halo clusters NGC 6287, NGC 6293, and NGC 6541, finding [Fe/H] = -2.01 +/- 0.05, -1.99 +/- 0.02, and -1.76 +/- 0.02, respectively, and our metallicity measurements are in good…

Astrophysics · Physics 2009-11-07 Jae-Woo Lee , Bruce W. Carney

NGC 6402 is among the most massive globular clusters in the Galaxy, but little is known about its detailed chemical composition. Therefore, we obtained radial velocities and/or chemical abundances of 11 elements for 41 red giant branch…

Solar and Stellar Astrophysics · Physics 2019-03-13 Christian I. Johnson , Nelson Caldwell , R. Michael Rich , Mario Mateo , John I. Bailey

We characterise the radial density, metallicity and flattening profile of the Milky Way's stellar halo, based on the large sample of 1757 spectroscopically confirmed giant stars from SDSS/SEGUE-2 after excising stars that were…

Astrophysics of Galaxies · Physics 2015-08-26 Xiang-Xiang Xue , Hans-Walter Rix , Zhibo Ma , Heather Morrison , Jo Bovy , Branimir Sesar , William Janesh

We present a chemical composition analysis of three dozen giant stars in the nearby ``CN-bimodal'' mildly metal-poor (<[Fe/H]> = -1.18) globular cluster M4. The analysis combined traditional spectroscopic abundance methods with…

Astrophysics · Physics 2007-05-23 Inese I. Ivans

We present carbon abundances of red giants in Milky Way globular clusters and dwarf spheroidal galaxies (dSphs). Our sample includes measurements of carbon abundances for 154 giants in the clusters NGC 2419, M68, and M15 and 398 giants in…

We have previously reported on chemical abundance trends with evolutionary state in the globular cluster NGC 6397 discovered in analyses of spectra taken with FLAMES at the VLT. Here, we reinvestigate the FLAMES-UVES sample of 18 stars,…

Solar and Stellar Astrophysics · Physics 2012-09-24 T. Nordlander , A. J. Korn , O. Richard , K. Lind

In this paper, we present photometry of 53 globular clusters (GCs) in the M31 outer halo, including the {\sl GALEX} FUV and NUV, SDSS $ugriz$, 15 intermediate-band filters of BATC, and 2MASS $JHK_{\rm s}$ bands. By comparing the multicolour…

Astrophysics of Galaxies · Physics 2019-03-06 Song Wang , Jun Ma , Jifeng Liu

Stellar atmospheric element abundance ratios of stars retain information about their birth conditions, helping elucidate their origin and nature. In this letter, we analyse and contrast the hydrostatic and explosive $\alpha$-element…

Astrophysics of Galaxies · Physics 2025-08-28 Danny Horta , Melissa K. Ness

Magnesium is one of the important elements in stellar physics as an electron donor and in Galactic Archaeology as a discriminator of different stellar populations. However, previous studies of Mg I and Mg II lines in metal-poor benchmark…

Solar and Stellar Astrophysics · Physics 2024-08-07 T. Matsuno , A. M. Amarsi , M. Carlos , P. E. Nissen

An abundance analysis based on a high-resolution spectrum is presented for a newly discovered post-AGB star in the globular cluster M79. The surprising result is that the iron abundance of the star is apparently about 0.6 dex less than that…

Solar and Stellar Astrophysics · Physics 2015-05-13 T. Sahin , David L. Lambert

Abundances for Fe, O, and the alpha-elements (Mg, Si, Ca, and Ti) have been derived from high resolution spectra of a sample of about one hundred dwarfs with high precision parallaxes measured by HIPPARCOS. The stars have metal abundances…

Astrophysics · Physics 2007-05-23 R. G. Gratton , E. Carretta , G. Clementini , C. Sneden

We present a new method to estimate the fraction of stars with chemical composition of first and second(s) generation(s) currently hosted in Galactic globular clusters (GCs). We compare cluster and field stars of similar metallicity in the…

Astrophysics of Galaxies · Physics 2015-06-16 Eugenio Carretta

The study of outer halo globular cluster (GC) populations can give insight into galaxy merging, globular cluster accretion and the origin of GCs. We use archival Subaru Hyper Suprime-Cam (HSC) data in concert with space-based GALEX, IRAC…

CONTEXT: Manganese is an iron-peak element and although the nucleosynthesis path that leads to its formation is fairly well understood, it remains unclear which objects, SN II and/or SN Ia, that contribute the majority of Mn to the…

Astrophysics · Physics 2008-11-26 S. Feltzing , M. Fohlman , T. Bensby

We present metallicities for red giant stars in the globular cluster NGC 6273 based on intermediate resolution GMOS-S spectra of the calcium triplet region. For the 42 radial velocity members with reliable calcium triplet line strength…

Solar and Stellar Astrophysics · Physics 2016-05-25 David Yong , Gary S. Da Costa , John E. Norris

[ABRIDGED] Metal-rich globular clusters provide important tracers of the formation of our Galaxy. Moreover, and not less important, they are very important calibrators for the derivation of properties of extra-galactic metal-rich stellar…

Astrophysics · Physics 2009-11-13 S. Feltzing , F. Primas , R. A. Johnson

We discuss the detailed composition of 28 extremely metal-poor dwarfs, 22 of which are from the Hamburg/ESO Survey, based on Keck Echelle spectra. Our sample has a median [Fe/H] of -2.7 dex, extends to -3.5 dex, and is somewhat less…