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Related papers: Toward more accurate RR Lyrae metallicities

200 papers

We report the first extensive model atmosphere and detailed chemical abundance study of eight RR Lyrae variable stars of c subclass throughout their pulsation cycles. Atmospheric parameters effective temperature, surface gravity,…

Solar and Stellar Astrophysics · Physics 2013-10-03 Jose Govea , Thomas Gomez , George W. Preston , Christopher Sneden

We have developed techniques to extract true iron abundances and surface gravities from spectra of the type provided by the multiple-object fibre-fed spectroscopic radial-velocity surveys underway with 2dF, HYDRA, NESSIE, and the…

Astrophysics · Physics 2007-05-23 J. Bryn Jones , Gerard Gilmore , Rosemary F. G. Wyse

We present a search and analysis of variable stars in the recently discovered Crater~II dwarf galaxy. Based on $B$, $V$, $I$ data collected with the Isaac Newton Telescope (FoV$\sim$0.44 square degrees) we detected 37 variable stars, of…

We present an analysis of the relative abundance features of a number of chemical elements in the atmospheres of metal-rich ($\rm{[Fe/H]} > -1.0$) Galactic-field RR~Lyrae variable stars and the kinematic characteristics of these stars. We…

Solar and Stellar Astrophysics · Physics 2024-08-07 M. L. Gozha , V. A. Marsakov , V. V. Koval'

We present new spectroscopic metal abundances for 74 RR Lyrae stars in omega Cen obtained with FLAMES. The well-known metallicity spread is visible among the RR Lyrae variables. The metal-intermediate (MInt) RR Lyrae stars ([Fe/H] ~ -1.2)…

Astrophysics · Physics 2009-11-11 A. Sollima , J. Borissova , M. Catelan , H. A. Smith , D. Minniti , C. Cacciari , F. R. Ferraro

The surface gravities and effective temperatures have been added to a compilative catalog published earlier, which includes the relative abundances of several chemical elements for 100 field RR Lyrae stars. These atmoshperic parameters and…

Astrophysics of Galaxies · Physics 2019-03-29 V. A. Marsakov , M. L. Gozha , V. V. Koval'

The GAIA satellite is likely to observe thousands of RR Lyrae stars within a small spectral window, between 8470A and 8750A, at a resolution of 11,500. In order to derive the metallicity of RR Lyrae stars from Gaia, we have obtained…

Solar and Stellar Astrophysics · Physics 2015-05-30 George Wallerstein , Thomas Gomez , Wenjin Huang

RR Lyrae stars play a central role in tracing phase-space structures within the Milky Way because they are easy to identify, are relatively luminous, and are found in large numbers in the Galactic bulge, disk, and halo. In this work, we…

We present a sample of 135,873 RR Lyrae stars (RRLs) with precise photometric-metallicity and distance estimates from our newly calibrated $P-\phi_{31}-R_{21}-$[Fe/H]/$P-R_{21}-$[Fe/H] and $G$ band absolute magnitude-metallicity relations.…

Solar and Stellar Astrophysics · Physics 2023-02-22 Xin-Yi Li , Yang Huang , Gao-Chao Liu , Timothy C. Beers , Hua-Wei Zhang

Stellar spectra derived from current multiple-object fiber-fed spectroscopic radial-velocity surveys, of the type feasible with, among other examples, AUTOFIB, 2dF, HYDRA, NESSIE, and the Sloan survey, differ significantly from those…

Astrophysics · Physics 2007-05-23 J. Bryn Jones , Rosemary F. G. Wyse , Gerard Gilmore

(abridged): Low resolution spectroscopy obtained with FORS2 at the Very Large Telescope (VLT) has been used to measure individual metal abundances ([Fe/H]) for 107 RR Lyrae stars, and trace the metal distribution of the oldest stellar…

We present a catalog of 5,290 RR Lyrae stars (RRLs) with metallicities estimated from spectra of the LAMOST Experiment for Galactic Understanding and Exploration (LEGUE) and the Sloan Extension for Galactic Understanding and Exploration…

Solar and Stellar Astrophysics · Physics 2020-04-15 G. -C. Liu , Y. Huang , H. -W. Zhang , M. -S. Xiang , J. -J. , Ren , B. -Q. Chen , H. -B. Yuan , C. Wang , Y. Yang , Z. -J. Tian , F. Wang , X. -W. Liu

Chemical analyses of late-type stars are usually carried out following the classical recipe: LTE line formation and homogeneous, plane-parallel, flux-constant, and LTE model atmospheres. We review different results in the literature that…

We present mean horizontal branch absolute magnitudes and iron abundances for a sample of 39 globular clusters. These quantities were calculated in an unprecedented homogeneous fashion based on Fourier decomposition of ligt curves of RR…

Solar and Stellar Astrophysics · Physics 2023-06-05 Armando Arellano Ferro

Low resolution spectra have been used to measure individual metal abundances of RR Lyrae stars in NGC 6441, a Galactic globular cluster known to have very unusual horizontal branch morphology and periods of the RR Lyrae stars for its high…

We present new period-$\phi_{31}$-[Fe/H] relations for first overtone RRL stars (RRc), calibrated over a broad range of metallicities ($-2.5 < \textrm{[Fe/H]}< 0.0$) utilizing the largest currently available set of Galactic halo field RRL…

We discuss the largest and most homogeneous spectroscopic dataset of field RR Lyrae variables (RRLs) available to date. We estimated abundances using both high-resolution and low-resolution ({\Delta S} method) spectra for fundamental (RRab)…

Spectroscopic iron-to-hydrogen ratios, radial velocities, atmospheric parameters, and new photometric analyses are presented for 41 RR Lyrae stars (and one probable high-amplitude delta Scuti star) located in the field-of-view of the Kepler…

Solar and Stellar Astrophysics · Physics 2015-06-16 James M. Nemec , Judith G. Cohen , Vincenzo Ripepi , Aliz Derekas , Pawel Moskalik , Branimir Sesar , Merieme Chadid , Hans Bruntt

We performed a detailed spectroscopic analysis of three extremely metal-poor RR Lyrae stars, exploring uncharted territories at these low metallicities for this class of stars. Using high-resolution spectra acquired with HARPS-N at TNG,…