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New information on the relations between the Galactic disks, the halo, and satellite galaxies is being obtained from elemental abundances of stars having metallicities in the range -1.5 < [Fe/H] < -0.5. The first results for a sample of 26…

Astrophysics · Physics 2015-05-13 Poul E. Nissen , William J. Schuster

Oscillations of the Sun and solar-like stars are believed to be excited stochastically by convection near the stellar surface. Theoretical modeling predicts that the resulting amplitude increases rapidly with the luminosity of the star.…

Astrophysics · Physics 2009-11-07 J. Christensen-Dalsgaard , H. Kjeldsen , J. A. Mattei

We present the chemical composition of 206 red giant branch stars members of the Small Magellanic Cloud (SMC) using optical, high-resolution spectra collected with the multi-object spectrograph FLAMES-GIRAFFE at the ESO Very Large…

Astrophysics of Galaxies · Physics 2023-03-29 A. Mucciarelli , A. Minelli , M. Bellazzini , C. Lardo , D. Romano , L. Origlia , F. R. Ferraro

The observational data of the near infrared bands (H and K) have been used for the modeling mean light curves. Also the visual observational data have been fitted the same. The infrared and visual mean light curves were compared. All…

Solar and Stellar Astrophysics · Physics 2016-07-14 L. S. Kudashkina

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…

Solar and Stellar Astrophysics · Physics 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

Photospheric abundances are presented for 27 elements from carbon to europium in 181 F-G dwarfs from a differential LTE analysis of high-resolution and high signal-to-noise spectra. Stellar $T_{\rm eff}$ were adopted from an infrared flux…

Astrophysics · Physics 2009-11-07 Bacham E. Reddy , Jocelyn Tomkin , David L. Lambert , Carlos Allende Prieto

We report chemical abundances of Na, Al, Zr, La, Nd, and Eu for 39 red giant branch (RGB) stars and 23 potential inner disk red clump stars located in Plaut-s low extinction window. We also measure lithium for a super Li-rich RGB star. The…

Solar and Stellar Astrophysics · Physics 2015-06-04 Christian I. Johnson , R. Michael Rich , Chiaki Kobayashi , Jon P. Fulbright

The chemical compositions of the stars in Milky Way (MW) satellite galaxies reveals the history of gas flows and star formation (SF) intensity. This talk presented a Keck/DEIMOS spectroscopic survey of the Fe, Mg, Si, Ca, and Ti abundances…

Astrophysics of Galaxies · Physics 2011-10-26 Evan N. Kirby

Carbon and oxygen abundances in F and G main-sequence stars ranging in metallicity from [Fe/H] = -1.6 to +0.5 are determined from a non-LTE analysis of CI and OI atomic lines in high-resolution spectra. Both C and O are good tracers of…

Astrophysics of Galaxies · Physics 2015-06-16 Poul E. Nissen , William J. Schuster

We provide a grid of PHOENIX spectra of red giant and supergiant stars, that extend through optical and near-IR wavelengths. For the first time, models are also provided with modified surface abundances of C, N and O, as a step towards…

Astrophysics · Physics 2009-11-13 A. Lançon , P. H. Hauschildt , D. Ladjal , M. Mouhcine

It has been suggested that hypernova remnants, with a substantial amount of energy in semi-relativistic ejecta, can accelerate intermediate mass or heavy nuclei to ultra-high energies and provide sufficient amount of energy in cosmic rays…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Ruo-Yu Liu , Xiang-Yu Wang

In the framework of an ESO Large Programme high quality spectra of 70 very metal-poor dwarfs and giants were obtained with the VLT-UVES combination. This paper reports the detailed analyses of the 35 giants of the sample. At the exception…

We present LTE chemical abundances for five red giants and one AGB star in the Galactic globular cluster (GC) M5 based on high resolution spectroscopy using the MIKE spectrograph on the Magellan 6.5-m Clay telescope. Our results are based…

Astrophysics of Galaxies · Physics 2015-05-18 Andreas Koch , Andrew McWilliam

We have used the Habitable Zone Planet Finder (HPF) to gather high resolution, high signal-to-noise near-infrared spectra of 13 field red horizontal-branch (RHB) stars, one open-cluster giant, and one very metal-poor halo red giant. The HPF…

We analyse the abundance ratios of the light elements Mg, Ca, C and N, relative to Fe, for 147 red-sequence galaxies in the Coma cluster and the Shapley Supercluster. The sample covers a six-magnitude range in luminosity, from giant…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Russell J. Smith , John R. Lucey , Michael J. Hudson , Terry J. Bridges

We derive the abundance of 19 elements in a sample of 64 stars with fundamental parameters very similar to solar, which minimizes the impact of systematic errors in our spectroscopic 1D-LTE differential analysis, using high-resolution…

Solar and Stellar Astrophysics · Physics 2009-12-10 I. Ramirez , J. Melendez , M. Asplund

The evolution of the Milky Way bulge and its relationship with the other Galactic populations is still poorly understood. The bulge has been suggested to be either a merger-driven classical bulge or the product of a dynamical instability of…

We report the abundance analysis of one red giant branch star in the metal-poor outer halo globular cluster NGC 5694. We obtain [Fe/H] = -1.93, based on the ionized lines, and our metallicity measurement is in good agreement with previous…

Astrophysics · Physics 2009-11-11 Jae-Woo Lee , Mercedes Lopez-Morales , Bruce W. Carney

We present a catalog of Fe, Mg, Si, Ca, and Ti abundances for 2961 red giant stars that are likely members of eight dwarf satellite galaxies of the Milky Way (MW): Sculptor, Fornax, Leo I, Sextans, Leo II, Canes Venatici I, Ursa Minor, and…

We present chemical abundances of Al and several Fe-Peak and neutron-capture elements for 13 red giant branch stars in the Galactic globular cluster NGC 6171 (M107). The abundances were determined using equivalent width and spectrum…

Solar and Stellar Astrophysics · Physics 2015-05-30 Julia E. O'Connell , Christian I. Johnson , Catherine A. Pilachowski , Geoffrey Burks
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