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Related papers: Mining Databases for M Dwarf Variability

200 papers

Locating ultra-cool companions to M dwarfs is important for constraining low-mass formation models, the measurement of sub-stellar dynamical masses and radii, and for testing ultra-cool evolutionary models. We present an optimised method…

Low-mass stars belonging to the M spectral type are the most numerous stars in our Galaxy, amounting to about two-thirds in number, and are found at the bottom of the main sequence in the H-R diagram. %Multi-wavelength studies on…

Solar and Stellar Astrophysics · Physics 2024-01-17 Samrat Ghosh , Soumen Mondal , Santosh Joshi , Sneh Lata , Rajib Kumbhakar

We present a spectroscopic catalog of 67082 M dwarfs from the LAMOST pilot survey. For each spectrum of the catalog, spectral subtype, radial velocity, equivalent width of H${\alpha}$, a number of prominent molecular band indices and the…

We present spectroscopic data for 16369 stellar targets within and/or toward 38 dwarf spheroidal galaxies and faint star clusters within the Milky Way halo environment. All spectra come from observations with the multi-object, fiber-fed…

Fifty-two magnetic white dwarfs have been identified in spectroscopic observations from the Sloan Digital Sky Survey (SDSS) obtained between mid-2002 and the end of 2004, including Data Releases 2 and 3. Though not as numerous nor as…

M-dwarfs are emerging in the literature as promising targets for detecting low-mass, Earth-like planets. An important step in this process is to determine the stellar parameters of the M-dwarf host star as accurately as possible. Different…

Solar and Stellar Astrophysics · Physics 2015-05-20 I. Bozhinova , Ch. Helling , A. Scholz

Stars are stretched by tidal interactions in tight binaries, and changes to their projected areas introduce photometric variations twice per orbit. Hermes et al. (2014, ApJ, 792, 39) utilized measurements of these ellipsoidal variations to…

Solar and Stellar Astrophysics · Physics 2018-09-18 K. J. Bell , J. J. Hermes , J. S. Kuszlewicz

We present evidence that there is an M dwarf problem similar to the previously identified G dwarf and K dwarf problems: the number of low-metallicity M dwarfs is not sufficient to match simple closed-box models of local Galactic chemical…

Solar and Stellar Astrophysics · Physics 2015-06-04 Vincent M. Woolf , Andrew A. West

Observations made using TESS revealed a sample of low mass stars which show a periodic modulation on a period $<0.2$~d. Surprisingly many of these Ultra Fast Rotating (UFR) stars showed no evidence of flare activity which would be expected…

Solar and Stellar Astrophysics · Physics 2022-02-23 Gavin Ramsay , Pasi Hakala , J. Gerry Doyle , Lauren Doyle , Stefano Bagnulo

We present metallicities, radial velocities and near-infrared spectral types for 447 M dwarfs determined from moderate resolution (R~2000) near-infrared (NIR) spectra obtained with IRTF/SpeX. These M dwarfs are targets of the MEarth Survey,…

We present photometric light curves for a sample of 21 ultra cool M and L dwarfs in the field and in the young open clusters sigma Orionis and the Pleiades. Evidence for variability with RMS amplitudes (in the I band) of 0.01 to 0.055…

Astrophysics · Physics 2010-11-23 C. A. L. Bailer-Jones , R. Mundt

In this paper, we study stellar light curves from the TESS satellite (Transiting Exoplanet Survey Satellite) for the presence of stellar flares. The main aim is to detect stellar flares using two-minutes cadence data and to perform…

Solar and Stellar Astrophysics · Physics 2022-08-31 Małgorzata Pietras , Robert Falewicz , Marek Siarkowski , Kamil Bicz , Paweł Preś

We present \textit{Spitzer Space Telescope} variability monitoring observations of three low-gravity L dwarfs with previous detections of variability in the near-IR, 2MASS J0045+16, 2MASS J0501-00 and 2MASS J1425-36. We detect significant,…

Relativistic effects dominate the emission of blazar jets complicating our understanding of their intrinsic properties. Although many methods have been proposed to account for them, the variability Doppler factor method has been shown to…

High Energy Astrophysical Phenomena · Physics 2018-10-31 I. Liodakis , T. Hovatta , D. Huppenkothen , S. Kiehlmann , W. Max-Moerbeck , A. C. S. Readhead

Stellar flares are sudden brightenings caused by magnetic reconnection and are frequently observed on late-type stars. High-cadence photometry of flares provides valuable insights into the mechanisms of these events, yet such observations…

Solar and Stellar Astrophysics · Physics 2026-02-26 B. Schmercz , B. Seli , K. Vida , L. Kriskovics , A. Görgei , K. Oláh , Zs. Regály

We have assembled a spectroscopic sample of low-mass dwarfs observed as part of the Sloan Digital Sky Survey along one Galactic sightline, designed to investigate the observable properties of the thin and thick disks. This sample of ~7400 K…

We present an analysis on the potential prevalence of mid infrared excesses in stars with and without planetary companions. Based on an extended database of stars detected with the ${\it WISE}$ satellite, we studied two stellar samples: one…

Solar and Stellar Astrophysics · Physics 2017-08-23 Raul F. Maldonado , Miguel Chavez , Emanuele Bertone , Fernando Cruz-Saenz de Miera

By using dark nebulae as opaque outer screens, the luminosity function of white dwarfs and M dwarfs has been studied. High-extinction areas towards the Orion A, Serpens and rho Oph cloud complexes were observed, covering a volume…

Astrophysics · Physics 2007-05-23 Leif Festin

Spectroscopic observations are essential for confirming associations, measuring kinematics, and determining stellar populations in dwarf galaxies. Here, we present Keck Cosmic Web Imager (KCWI) spectra for 12 MATLAS survey dwarfs. For 9, we…

Stellar variability in the near-infrared (NIR) remains largely unexplored. The exploitation of public science archives with data-mining methods offers a perspective for the time-domain exploration of the NIR sky. We perform a comprehensive…

Solar and Stellar Astrophysics · Physics 2016-08-10 C. E. Ferreira Lopes , I. Dékány , M. Catelan , N. J. G. Cross , R. Angeloni , I. C. Leão , J. R. De Medeiros