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Related papers: Mining Databases for M Dwarf Variability

200 papers

Using the Gemini infrared camera on the 3-meter Shane telescope at Lick Observatory, we have searched for broad-band J and K' photometric variability for a sample of 15 L and T-type brown dwarfs, including 7 suspected spectral binaries.…

Solar and Stellar Astrophysics · Physics 2013-02-12 Harish Khandrika , Adam Burgasser , Carl Melis , Christopher Luk , Emily Bowsher , Brandon Swift

This paper presents new trigonometric parallaxes and proper motions for 214 stars. The measurements were made at the US Naval Observatory Flagstaff Station (NOFS) between 1989 and 2017, and the average uncertainty in the parallax values is…

This study presents all available, multi-epoch 3.6 and 4.5 $\mu$m photometry from Spitzer Space Telescope observations of white dwarf debris disks, including weekly cadence observations of 16 relatively bright systems, and 5 h staring-mode…

We characterize the magnetic activity of M dwarfs to provide the planet community with information on the energy input from the star; in particular, in addition to the frequency of optical flares directly observed with TESS, we aim at…

Solar and Stellar Astrophysics · Physics 2022-09-14 B. Stelzer , M. Bogner , E. Magaudda , St. Raetz

This paper reports updated results on our systematic mining of the DENIS database for nearby very cool M-dwarfs (M6V-M8V, 2.0<I-J<3.0, photometric distance within 30 pc), We calibrate the DENIS (M_I, I-J) colour-luminosity relationship from…

A wide range of phenomena, from explosive transients to active galactic nuclei, exhibit variability at radio wavelengths on timescales of a few years. Characterizing the rate and scale of variability in the radio sky can provide keen…

Astrophysics of Galaxies · Physics 2026-05-21 Yjan A. Gordon , Peter S. Ferguson , Michael N. Martinez , Eric J. Hooper

With the launch of the {\em Wide-field Infrared Survey Explorer} ({\em WISE}), a new era of detecting planetary debris and brown dwarfs around white dwarfs (WDs) has begun with the {\em WISE} InfraRed Excesses around Degenerates (WIRED)…

Solar and Stellar Astrophysics · Physics 2015-05-30 J. H. Debes , D. W. Hoard , S. Wachter , D. T. Leisawitz , M. Cohen

We describe advances on a method designed to derive accurate parameters of M dwarfs. Our analysis consists in comparing high-resolution infrared spectra acquired with the near-infrared spectro-polarimeter SPIRou to synthetic spectra…

Solar and Stellar Astrophysics · Physics 2022-09-28 P. I. Cristofari , J. -F. Donati , T. Masseron , P. Fouqué , C. Moutou , A. Carmona , E. Artigau , E. Martioli , G. Hébrard , E. Gaidos , X. Delfosse

The EXTraS project, based on data collected with the XMM-Newton observatory, provided us with a vast amount of light curves for X-ray sources. For each light curve, EXTraS also provided us with a set of features (https://extras.inaf.it). We…

High Energy Astrophysical Phenomena · Physics 2026-04-08 Mario Pasquato , Martino Marelli , Andrea De Luca , Ruben Salvaterra , Gaia Carenini , Andrea Belfiore , Andrea Tiengo , Paolo Esposito

We study the relationship between Galactic location ($R, Z$) and photometric activity for 3.6 million M dwarf stars within 1 kpc of the Sun. For this purpose, we identify 906 unique flare events as a proxy for magnetic activity from the…

Solar and Stellar Astrophysics · Physics 2022-10-05 Seo-Won Chang , Christian Wolf , Christopher A. Onken

We report the results of our HST snapshot survey with the ACS HRC PR200L prism, designed to measure the near-UV emission in a sample of nearby M dwarfs. 33 stars were observed, spanning the mass range from 0.1 - 0.6 solar masses (T_eff ~…

Astrophysics · Physics 2009-11-13 Lucianne M. Walkowicz , Christopher M. Johns-Krull , Suzanne L. Hawley

There are several strong K I lines found in the spectra of M dwarfs, among them the doublet near 7700 AA and another doublet near 12 500 AA. We study these optical and near-infrared doublets in a sample of 324 M dwarfs, observed with…

Metallicity is a fundamental parameter that contributes to the physical characteristics of a star. However, the low temperatures and complex molecules present in M dwarf atmospheres make it difficult to measure their metallicities using…

Knowledge of late K and M dwarf metallicities can be used to guide planet searches and constrain planet formation models. However, the determination of metallicities of late-type stars is difficult because visible wavelength spectra of…

Solar and Stellar Astrophysics · Physics 2014-05-16 Andrew W. Mann , John M. Brewer , Eric Gaidos , Sebastien Lepine , Eric J. Hilton

We present the initial results from an in-depth re-examination of the MACHO project Large Magellanic Cloud database to identify and characterize stellar variability near the intersection of the instability strip and the main sequence. This…

Astrophysics · Physics 2010-12-09 D. Lepischak , D. L. Welch

To obtain a better statistics on the occurrence of magnetism among white dwarfs, we searched the spectra of the hydrogen atmosphere white dwarf stars (DAs) in the Data Release 7 of the Sloan Digital Sky Survey (SDSS) for Zeeman splittings…

Accurate stellar properties are essential for precise stellar astrophysics and exoplanetary science. In the M-dwarf regime, much effort has gone into defining empirical relations that can use readily accessible observables to assess…

Solar and Stellar Astrophysics · Physics 2021-09-29 J. Sebastian Pineda , Allison Youngblood , Kevin France

We use data from the Transiting Exoplanet Survey Satellite (TESS) to search for, and set limits on, optical to near-infrared photometric variability of the well-vetted, candidate James Webb Space Telescope (JWST) spectrophotometric…

This work presents the first large-scale photometric variability survey of the intermediate age (~200 Myr) open cluster M11. Thirteen nights of data over two observing seasons were analyzed (using crowded field and ensemble photometry…

Astrophysics · Physics 2008-11-26 Jonathan R. Hargis , Eric L. Sandquist , David H. Bradstreet

We present an analysis of the photometric variability of M dwarfs in the WFCAM Transit Survey. Although periodic lightcurve variability in low mass stars is generally dominated by photospheric star spot activity, M dwarf variability in the…