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Related papers: Mining Databases for M Dwarf Variability

200 papers

The Sloan Digital Sky Survey (SDSS), originally targeted at quasi-stellar objects, has provided us with a wealth of astronomical byproducts through the last decade. Since then, the number of white dwarfs (WDs) with physically bound…

Solar and Stellar Astrophysics · Physics 2015-03-19 René Heller , Axel D. Schwope , Roy H. Østensen

We describe a method for accurately determining M dwarf metallicities with spectral synthesis based on abundance analyses of visual binary stars. We obtained high resolution, high signal-to-noise spectra of each component of five visual…

An extensive sample of M, L and T dwarfs identified in the Sloan Digital Sky Survey (SDSS) has been compiled. The sample of 718 dwarfs includes 677 new objects (629 M dwarfs, 48 L dwarfs) together with 41 that have been previously…

Astrophysics · Physics 2019-08-15 S. L. Hawley , K. R. Covey , G. R. Knapp , D. A. Golimowski , X. Fan

We have carried out a multifrequency analysis of the radio variability of blazars, exploiting the data obtained during the extensive monitoring programs carried out at the University of Michigan Radio Astronomy Observatory (UMRAO, at 4.8,…

We assess the photometric variability of nine stars with spectroscopic Teff and log(g) values from the ELM Survey that locate them near the empirical extremely low-mass (ELM) white dwarf instability strip. We discover three new pulsating…

A recent cross-correlation between the SDSS DR7 White Dwarf Catalog with the Wide-Field Infrared Survey Explorer ($WISE$) all-sky photometry at 3.4, 4.6, 12, and 22 microns performed by Debes et al. (2011) resulted in the discovery of 52…

Astrophysics of Galaxies · Physics 2015-06-18 Sara D. Barber , Mukremin Kilic , Warren R. Brown , A. Gianninas

The photometry from 2MASS, UCAC3 and SuperCosmos catalogues together with the proper motions from the Tycho-2, XPM and UCAC3 catalogues are used to select the all-sky samples of 34 white dwarfs, 1996 evolved and 7769 unevolved subdwarfs…

Solar and Stellar Astrophysics · Physics 2015-05-18 George A. Gontcharov , Anisa T. Bajkova , Peter N. Fedorov , Vladimir S. Akhmetov

The Mt. Suhora M\,dwarf survey searching for pulsations in low mass main sequence stars has acquired CCD photometry of 46 M\,dwarf stars during the first year of the project (Baran et al 2011). As a by-product of this search hundreds field…

Solar and Stellar Astrophysics · Physics 2011-06-24 L. Fox Machado , A. S. Baran , M. Winiarski , J. Krzesiński , M. Dróżdz

We study the relationship between the mid-infrared and sub-mm variability of deeply embedded protostars using the multi-epoch data from the Wide Infrared Survey Explorer ($WISE$/NEOWISE) and the ongoing James Clerk Maxwell Telescope (JCMT)…

We have performed a multiparametric analysis of luminosity data for a sample of 234 normal spiral and irregular galaxies observed in X-rays with the {\it Einstein Observatory}. This sample is representative of S and Irr galaxies, with a…

Astrophysics · Physics 2009-11-06 Alice Shapley , G. Fabbiano , P. B. Eskridge

We present deep H-band surface photometry and analysis of 40 Local Volume galaxies, a sample primarily composed of dwarf irregulars in the Cen A group, obtained using the IRIS2 detector at the 3.9m Anglo-Australian Telescope. We probe to a…

Astrophysics of Galaxies · Physics 2014-08-14 T. Young , H. Jerjen , Á. R. López-Sánchez , B. S. Koribalski

The stellar evolution theory of massive stars remains uncalibrated with high-precision photometric observational data mainly due to a small number of luminous stars that are monitored from space. Automated all-sky surveys have revealed…

Solar and Stellar Astrophysics · Physics 2017-02-08 Jaan Laur , Indrek Kolka , Tõnis Eenmäe , Taavi Tuvikene , Laurits Leedjärv

On 2017-09-20 we observed GJ 4334, an M5V dwarf rotating with a period of 23.5 days, simultaneously with both the Space Telescope Imaging Spectrograph aboard Hubble (1160 -- 1710 Angstroms) and the Dual Imaging Spectrograph mounted on the…

We use broadband photometry and low-resolution spectra of a complete sample of late-K and M dwarfs brighter than I=22 in three fields at high galactic latitude to study issues relating to galactic structure and large scale abundance…

Astrophysics · Physics 2009-10-30 I. N. Reid , J. E. Gizis , J. G. Cohen , M. A. Pahre , D. W. Hogg , L. Cowie , E. Hu , A. Songaila

Stellar flares are powerful bursts of electromagnetic radiation triggered by magnetic reconnection in the chromosphere of stars, occurring frequently and intensely on active M dwarfs. While missions like TESS and Kepler have studied regular…

Solar and Stellar Astrophysics · Physics 2025-07-16 J. Poyatos , O. Fors , J. M. Gómez Cama , I. Ribas

We present a method to reliably select variable white dwarfs from large area time domain surveys and apply this method in a pilot study to search for pulsating white dwarfs in the Sloan Digital Sky Survey Stripe 82. From a sample 400…

Solar and Stellar Astrophysics · Physics 2015-10-29 Nicola Pietro Gentile Fusillo , J. J. Hermes , Boris T. Gänsicke

Stars exhibit a bewildering variety of variable behaviors ranging from explosive magnetic flares to stochastically changing accretion to periodic pulsations or rotations. The principal LSST surveys will have cadences too sparse and…

Instrumentation and Methods for Astrophysics · Physics 2019-01-24 Eric D. Feigelson , Frederica Bianco , Sara Bonito

Based on the near infrared spectra of 42 M dwarfs, carbon abundances are determined from the ro-vibrational lines of CO 2-0 band. We use Teff values based on the angular diameters if available or apply a logTeff - M3.4 (the absolute…

Solar and Stellar Astrophysics · Physics 2015-06-22 Takashi Tsuji , Tadashi Nakajima

Roughly 2% of white dwarfs harbor planetary debris disks detectable via infrared excesses, but only a few percent of these disks show a gaseous component, distinguished by their double-peaked emission at the near-infrared calcium triplet.…

Solar and Stellar Astrophysics · Physics 2024-06-28 Joseph A. Guidry , J. J. Hermes , Kishalay De , Lou Baya Ould Rouis , Brison B. Ewing , B. C. Kaiser

Most M dwarfs show higher chromospheric activity, often exceeding solar levels. Characterizing stellar activity is essential, particularly since these stars are prime targets in the search for habitable exoplanets. We investigate the…

Solar and Stellar Astrophysics · Physics 2026-01-14 A. S. Rajpurohit , V. Kumar , K. Srivastava Mudit , L. Labadie , K. Rajpurohit , J. G. Fernandez-Trincado
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