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相关论文: A Globular Cluster Metallicity Scale Based on the …

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When using Fe as a surrogate for ``metallicity'', the metallicity is best represented by the dominant species of Fe. Accordingly, we have derived a new globular cluster metallicity scale based on the equivalent widths of FeII lines measured…

天体物理学 · 物理学 2007-05-23 R. P. Kraft , I. I. Ivans

M 2 has been claimed to posses three distinct stellar components that are enhanced in iron relative to each other. We use equivalent width measurements from 14 red giant branch stars from which Yong et al. detect a $\sim$0.8 dex wide,…

太阳与恒星天体物理 · 物理学 2016-01-27 C. Lardo , A. Mucciarelli , N. Bastian

We have obtained high-res, high S/N ratio CCD echelle spectra of 10 bright red giants in 3 GCs (47Tuc, NGC6752 and NGC6397) roughly spanning the range of metallicities of the galactic GC system; they reveal no evidence of star to star…

天体物理学 · 物理学 2009-07-28 E. Carretta , R. G. Gratton

How can we accurately determine the metallicity of faint red giant stars in nearby galaxies? The equivalent widths of the broad absorption lines from Ca II at 8498, 8542, and 8662 Angstrom (the calcium triplet) have shown a smooth…

天体物理学 · 物理学 2007-05-23 T. Bosler , T. Smecker-Hane , A. McWilliam

We present a study of the stellar parameters and iron abundances of 18 giant stars in 6 open clusters. The analysis was based on high-resolution and high-S/N spectra obtained with the UVES spectrograph (VLT-UT2). The results complement our…

太阳与恒星天体物理 · 物理学 2015-06-03 N. C. Santos , C. Lovis , J. Melendez , M. Montalto , D. Naef , G. Pace

We present abundances of globular clusters in the Milky Way and Fornax from integrated light spectra. Our goal is to evaluate the consistency of the integrated light analysis relative to standard abundance analysis for individual stars in…

星系天体物理 · 物理学 2017-01-11 J. E. Colucci , R. A. Bernstein , A. McWilliam

We have obtained spectra with resolution 2.5 Angstroms in the region 7500-9500 Angstroms for 116 red giants in 5 Galactic globular clusters and 6 old open clusters (5 with published metallicities, and one previously unmeasured). The…

天体物理学 · 物理学 2009-11-10 A. A. Cole , T. A. Smecker-Hane , E. Tolstoy , T. L. Bosler , J. S. Gallagher

Aims. We use the spectra of more than 30,000 red giant branch (RGB) stars in 25 globular clusters (GC), obtained within the MUSE survey of Galactic globular clusters, to calibrate the Ca II triplet (CaT) metallicity relation and derive…

We have derived Mn abundances for more than 200 stars in 19 globular clusters. In addition, Mn abundance determinations have been made for a comparable number of halo field and disk stars possessing an overlapping range of metallicities and…

天体物理学 · 物理学 2008-11-26 J. S. Sobeck , I. I. Ivans , J. A. Simmerer , C. Sneden , P. Hoeflich , J. P. Fulbright , R. P. Kraft

We have collected spectra of about 2000 red giant branch (RGB) stars in 19 Galactic globular clusters (GC) using FLAMES@VLT (about 100 star with GIRAFFE and about 10 with UVES, respectively, in each GC). These observations provide an…

星系天体物理 · 物理学 2015-05-14 Eugenio Carretta , Angela Bragaglia , Raffaele Gratton , Valentina D'Orazi , Sara Lucatello

Measurements are presented and analyzed of the strength of the Ca II triplet lines in red giants in Galactic globular and open clusters, and in a sample of red giants in the LMC disk that have significantly different [Ca/Fe] abundance…

太阳与恒星天体物理 · 物理学 2015-11-11 G. S. Da Costa

(ABRIDGED) Globular clusters trace the formation and evolution of the Milky Way and surrounding galaxies, and outline their chemical enrichment history. To accomplish these tasks it is important to have large samples of clusters with…

NGC 362 is a non-common Type II Galactic globular cluster, showing a complex pseudo two-color diagram or 'chromosome map'. The clear separation of its stellar populations in the color-magnitude diagram and the distribution of the giant…

星系天体物理 · 物理学 2022-07-13 C. Vargas , S. Villanova , D. Geisler , C. Muñoz , L. Monaco , J. O'Connell , Ata Sarajedini

Medium resolution (R=4,000 to 9,000) spectra of the near infrared Ca II lines (at 8498, 8542, and 8662 A) in M31 globular cluster integrated light spectra are presented. In individual stars the Ca II triplet (CaT) traces stellar…

星系天体物理 · 物理学 2015-12-23 Charli M. Sakari , George Wallerstein

The globular cluster HP~1 is projected at only 3.33 degrees from the Galactic center. Together with its distance, this makes it one of the most central globular clusters in the Milky Way. It has a blue horizontal branch (BHB) and a…

太阳与恒星天体物理 · 物理学 2016-06-22 B. Barbuy , E. Cantelli , A. Vemado , H. Ernandes , S. Ortolani , I. Saviane , E. Bica , D. Minniti , B. Dias , Y. Momany , V. Hill , M. Zoccali , C. Siqueira-Mello

We present chemical abundances for O, Na, Mg, Al, Si, Ca, Ti and Fe in eight red giants and one turnoff star in the metal rich globular cluster 47 Tuc, based on spectroscopy with the MIKE high resolution spectrograph on the Magellan 6.5-m…

天体物理学 · 物理学 2009-11-13 Andreas Koch , Andrew McWilliam

We present radial velocities, Fe, and Al abundances for 180 red giant branch (RGB) stars in the Galactic globular cluster Omega Centauri ($\omega$ Cen). The majority of our data lie in the range 11.0$<$V$<$13.5, which covers the RGB from…

天体物理学 · 物理学 2009-11-13 Christian I. Johnson , Catherine A. Pilachowski , Jennifer Simmerer , Dustin Schwenk

We obtained spectra of red giants in 15 Small Magellanic Cloud (SMC) clusters in the region of the CaII lines with FORS2 on the Very Large Telescope (VLT). We determined the mean metallicity and radial velocity with mean errors of 0.05 dex…

太阳与恒星天体物理 · 物理学 2015-06-24 M. C. Parisi , D. Geisler , J. J. Clariá , S. Villanova , N. Marcionni , A. Sarajedini , A. J. Grocholski

We have obtained metallicities of ~ 360 red giant stars distributed in 15 Small Magellanic Cloud (SMC) fields from near-infrared spectra covering the CaII triplet lines using the VLT + FORS2. The errors of the derived [Fe/H] values range…

太阳与恒星天体物理 · 物理学 2015-05-14 M. C. Parisi , D. Geisler , A. J. Grocholski , J. J. Claria , A. Sarajedini

We present a technique that applies spectral synthesis to medium resolution spectroscopy (MRS, R ~ 6000) in the red (6300 A < lambda < 9100 A) to measure [Fe/H] and [alpha/Fe] of individual red giant stars over a wide metallicity range. We…

天体物理学 · 物理学 2008-08-09 Evan N. Kirby , Puragra Guhathakurta , Christopher Sneden
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