Results 41 to 50 of about 23,116,162 (197)
Magnetic Field Measurements of Low-mass Stars from High-resolution Near-infrared IGRINS Spectra
The Astronomical Journal, 2023 We present average magnetic field measurements derived from high-resolution near-infrared IGRINS spectra of a carefully selected sample of 28 M dwarfs. All 28 have reported magnetic field strengths in the literature.
Eunkyu Han +3 more
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The theoretical instability strip of M dwarf stars [PDF]
Monthly Notices of the Royal Astronomical Society, 2013 The overstability of the fundamental radial mode in M dwarf models was theoretically predicted by Rodríguez-López et al. (2012). The periods were found to be in the ranges ~25-40 min and ~4-8 h, depending on stellar age and excitation mechanism. We have extended our initial M dwarf model grid in mass, metallicity, and mixing length parameter.
Rodríguez-López, Cristina +4 more
openaire +3 more sources
Stellar Characterization and Radius Inflation of Hyades M-dwarf Stars from the APOGEE Survey
The Astrophysical Journal, 2023 We present a spectroscopic analysis of a sample of 48 M-dwarf stars (0.2 M _⊙ < M < 0.6 M _⊙ ) from the Hyades open cluster using high-resolution H -band spectra from the Sloan Digital Sky Survey/Apache Point Observatory Galactic Evolution Experiment ...
Fábio Wanderley +25 more
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Inhomogeneous structure in the chromospheres of dwarf M stars [PDF]
Monthly Notices of the Royal Astronomical Society, 1991 Linear combinations of observed spectra of the H-alpha and Ca-II resonance and IR lines from the chromospheres of a quiet (Gl 1) and an active (Gl 735) dwarf-M star are compared with the corresponding spectra from a star of intermediate activity (Gl 887).
N. J. Turner, L. E. Cram, R. D. Robinson
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Searching for Rotational and Activity Signals in M Dwarf Stars [PDF]
, 2017 We search for signals coming from M dwarf stars through variations caused by stellar surface activity. The aims of this work are to find the stellar rotation period of M dwarf stars and check them against known planetary signals. We used photometric ASAS
Zayer, Imad
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Detection of Young Massive White Dwarfs in Core-collapsed Globular Cluster NGC 362
The Astrophysical Journal LettersCore-collapsed globular clusters are ideal targets to explore the presence of stellar collision products. Here, we have studied 17 far-UV bright white dwarf (WD) members in the globular cluster NGC 362 using data obtained from the Ultra Violet Imaging ...
R. K. S. Yadav +4 more
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Chemical and kinematical evolution in nearby dwarf spheroidal galaxies [PDF]
, 2006 Dwarf spheroidal (dSph) galaxies are the least massive and luminous objects known to exist. These galaxies are often considered as the fossil building blocks of massive systems predicted by some cosmological models.
Koch, Andreas
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The Astrophysical Journal Supplement SeriesWe analyze a catalog comprising 781,232 spectra from 641,095 M dwarf stars from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) low-resolution spectroscopic data release 9.
Wenjie Li +5 more
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Longitudinally Modulated Dynamo Action in Simulated M-dwarf Stars
The Astrophysical Journal, 2022 Abstract M-dwarf stars are well known for the intense magnetic activity that many of them exhibit. In cool stars with near-surface convection zones, this magnetic activity is thought to be driven largely by the interplay of convection and the large-scale differential rotation and circulations it establishes.
Connor P. Bice, Juri Toomre
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Overestimated Pressure Broadening Misleads Model Spectra in Cool M Dwarf Stars
The Astrophysical Journal LettersAvailable one-dimensional stellar models fail to reproduce the observed spectrum of the ultracool M dwarf TRAPPIST-1. In particular, current models predict strong iron hydride (FeH) absorption due to the Wing–Ford bands at 0.99 μ m, yet this spectral ...
Ana Glidden +3 more
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