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Related papers: Temperatures and Metallicities of M dwarfs in the …

200 papers

We provide a catalogue of atmospheric parameters for 1,806,921 cool dwarfs from Gaia DR3 which lie within the range covered by LAMOST cool dwarf spectroscopic parameters: 3200 K < T_{eff}< 4300 K, -0.8 < [M/H] < 0.2 dex, and 4.5 <log{g} <…

Solar and Stellar Astrophysics · Physics 2023-11-16 Cai-Xia Qu , A-Li Luo , Rui Wang , Hugh R. A. Jones , Bing Du , Xiang-Lei Chen , You-Fen Wang

We present a spectral analysis of the binary G 224-58 AB that consists of the coolest M extreme subdwarf (esdM5.5) and a brighter primary (esdK5). This binary may serve as a benchmark for metallicity measurement calibrations and as a…

Solar and Stellar Astrophysics · Physics 2015-10-21 Ya. V. Pavlenko , Z. H. Zhang , M. C. Gálvez-Ortiz , I. O. Kushniruk , H. R. A. Jones

Despite their large number in the Galaxy, M dwarfs remain elusive objects and the modeling of their photospheres has long remained a challenge (molecular opacities, dust cloud formation). Our objectives are to validate the BT-Settl model…

Solar and Stellar Astrophysics · Physics 2015-06-15 A. S. Rajpurohit , C. Reylé , F. Allard , D. Homeier , M. Schultheis , M. S. Bessell , A. C. Robin

We present a spectro-photometric analysis of 2880 cool white dwarfs within 100 pc of the Sun and cooler than Teff = 10,000 K, with grizy Pan-STARRS photometry and Gaia trigonometric parallaxes available. We also supplement our data sets…

Solar and Stellar Astrophysics · Physics 2022-12-28 Alexandre Caron , Pierre Bergeron , Simon Blouin , Sandy K. Leggett

We present a comparison of low-resolution spectra of 60 stars covering the whole M-dwarf sequence. Using the most recent PHOENIX BT-Settl stellar model atmospheres (see paper by F. Allard, in this book) we do a first quantitative compari-…

Solar and Stellar Astrophysics · Physics 2011-02-09 C. Reyle , A. S. Rajpurohit , M. Schultheis , F. Allard

Brown dwarf spectra are rich in information revealing of the chemical and physical processes operating in their atmospheres. We apply a recently developed atmospheric retrieval tool to an ensemble of late T-dwarf (600-800K) near infrared…

We present fundamental atmospheric parameters (Teff and log g) and metallicities ([M/H]) for 507,513 M dwarf stars using low-resolution spectra (R~1800) from LAMOST DR10. By employing Cycle-StarNet, an innovative domain adaptation approach,…

Solar and Stellar Astrophysics · Physics 2025-02-05 Shuo Zhang , Hua-Wei Zhang , Yuan-Sen Ting , Rui Wang , Teaghan O'Briain , Hugh R. A. Jones , Derek Homeier , A-Li Luo

M subdwarfs are metal poor and cool stars. They are important probes of the old galactic populations. However, they remain elusive due to their low luminosity. Observational and modeling efforts are required to fully understand the physics…

Solar and Stellar Astrophysics · Physics 2013-09-19 A. S. Rajpurohit , C. Reyle , M. Schultheis , F. Allard

We present precise measurements of radial (RV) and projected rotational ($v\sin{i}$) velocities, effective temperatures, and surface gravities of a sample of 258 M6 to L2 dwarfs with multi-epoch, high-resolution ($\lambda/\Delta\lambda$ =…

We present a large forward-modeling analysis for 55 late-T (T7-T9) dwarfs, using low-resolution ($R\approx150$) near-infrared spectra and cloudless Sonora-Bobcat model atmospheres. We derive the objects' effective temperatures, surface…

Solar and Stellar Astrophysics · Physics 2021-11-17 Zhoujian Zhang , Michael C. Liu , Mark S. Marley , Michael R. Line , William M. J. Best

We present precise photometric estimates of stellar parameters, including effective temperature, metallicity, luminosity classification, distance, and stellar age, for nearly 26 million stars using the methodology developed in the first…

APOGEE and GALAH are two high resolution multi-object spectroscopic surveys that provide fundamental stellar parameters and multiple elemental abundance estimates for about half a million stars in the Milky Way. Both surveys observe in…

To accurately interpret the observed properties of exoplanets, it is necessary to first obtain a detailed understanding of host star properties. However, physical models that analyze stellar properties on a per-star basis can become…

Earth and Planetary Astrophysics · Physics 2020-08-05 Malena Rice , John Brewer

We present interferometric diameter measurements of 21 K- and M- dwarfs made with the CHARA Array. This sample is enhanced by literature radii measurements to form a data set of 33 K-M dwarfs with diameters measured to better than 5%. For…

We present empirical metallicity-dependent calibrations of effective temperature against colours for dwarfs of luminosity classes IV and V and for giants of luminosity classes II and III, based on a collection from the literature of about…

Solar and Stellar Astrophysics · Physics 2015-10-28 Yang Huang , Xiao-Wei Liu , Hai-Bo Yuan , Mao-sheng Xiang , Bing-Qiu Chen , Hua-Wei Zhang

We report the first survey of chemical abundances in M and K dwarf stars using atomic absorption lines in high resolution spectra. We have measured Fe and Ti abundances in 35 M and K dwarf stars using equivalent widths measured from (lambda…

Astrophysics · Physics 2009-11-10 Vincent M. Woolf , George Wallerstein

We present an all-sky catalog of 2970 nearby ($d \lesssim 50$ pc), bright ($J< 9$) M- or late K-type dwarf stars, 86% of which have been confirmed by spectroscopy. This catalog will be useful for searches for Earth-size and possibly…

Solar and Stellar Astrophysics · Physics 2015-06-22 E. Gaidos , A. W. Mann , S. Lepine , A. Buccino , D. James , M. Ansdell , R. Petrucci , P. Mauas , E. J. Hilton

The spectra of brown dwarfs are key to exploring the chemistry and physics that take place in their atmospheres. Late-T dwarf spectra are particularly diagnostic due to their relatively cloud-free atmospheres and deep molecular bands. With…

We present a method to select hot subdwarf stars with A to M-type companions using photometric selection criteria. We cover a wide range in wavelength by combining GALEX ultraviolet data, optical photometry from the SDSS and the Carlsberg…

Solar and Stellar Astrophysics · Physics 2015-06-05 J. Girven , D. Steeghs , U. Heber , B. T. Gänsicke , T. R. Marsh , E. Breedt , C. M. Copperwheat , S. Pyrzas , P. Longa Peña

We present $Spitzer$ IRS 5--14 $\mu$m spectra and 16 $\mu$m and 22 $\mu$m photometry of the T2.5 companion to the $\sim$300 Myr-old G0V star HN Peg. We incorporate previous 0.8--5 $\mu$m observations to obtain the most comprehensive…

Solar and Stellar Astrophysics · Physics 2021-10-27 Genaro Suárez , Stanimir Metchev , Sandy K. Leggett , Didier Saumon , Mark S. Marley