Results 41 to 50 of about 560 (161)
The Mass Dependence of Hα Emission and Stellar Spindown for Fully Convective M Dwarfs
The Astrophysical JournalFully convective M dwarfs typically remain rapidly rotating and magnetically active for billions of years, followed by an abrupt and mass-dependent transition to slow rotation and quiescence.
Emily K. Pass +6 more
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Two planetary systems with transiting Earth-sized and super-Earth planets orbiting late-type dwarf stars [PDF]
Monthly Notices of the Royal Astronomical Society: Letters, 2018 ABSTRACTWe present two new planetary systems found around cool dwarf stars with data from the K2 mission. The first system was found in K2-239 (EPIC 248545986), characterized in this work as M3.0V and observed in the 14th campaign of K2. It consists of three Earth-sized transiting planets with radii of 1.1, 1.0, and 1.1 R⊕, showing a compact ...
Alonso, E Díez +11 more
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The Influence of Chromospheric Activity on Line Formation
The Astrophysical JournalOne of the primary sources of stellar spectral variability is magnetic activity. While our current understanding of chromospheric activity is largely derived from specific lines sensitive to chromospheric heating, such as the Ca ii H and K doublet ...
Mariela C. Vieytes +2 more
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Extending the Search for Counterrotating Gas and Stars in Galaxies: A Study of Late-Type Dwarfs
, 2005 In a previous study on gas-stellar counterrotation for a large sample of E/S0 and spiral galaxies (Kannappan & Fabricant 2001), two dwarf irregular galaxies were included, of which one was tentatively identified as a counterrotator. Here we extend the search for counterrotation to include 10 more irregular/spiral dwarf galaxies.
Guie, J. M. +3 more
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AFar Ultraviolet Spectroscopic ExplorerSurvey of Late‐Type Dwarf Stars
The Astrophysical Journal, 2002 We describe the 910-1180 Aspectra of seven late-type dwarf stars obtained with the Far Ultraviolet Spec- troscopic Explorer (FUSE) satellite. The stars include Altair (A7 IV), Procyon (F5 IV-V), Cen A (G2 V), AB Dor (K1 V), Cen B (K2 V), Eri (K2 V), and AU Mic (M0 V). We present line identifications, fluxes, Doppler shifts, and widths.
Seth Redfield +7 more
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The Astrophysical JournalWe present new JWST/NIRCam observations of the interacting dwarf galaxy system NGC 4485–NGC 4490 (aka Arp 269), obtained as part of the Cycle 1 Feedback in Emerging Extragalactic Star Clusters (FEAST) program. NGC 4485 and NGC 4490 form the closest known
Giacomo Bortolini +25 more
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Stellar populations and star formation histories in late-type dwarfs
, 2003 7 pages, 4 encapsulated .ps figures. Review presented at the "Stars in galaxies" meeting held in La Palma (Spain) in March 2003. Mem.S.A.It.
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Analysis of Six Long-period Low-mass Eclipsing Binaries
The Astronomical JournalThe radius inflation is predominantly observed in short-period, low-mass stellar systems, while being rarely detected in long-period binaries. Using Transiting Exoplanet Survey Satellite photometric and Large Sky Area Multi-Object Fiber Spectroscopic ...
Yang Pan +4 more
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Advances in Astronomy, 2010 In this tutorial paper we summarize how the star formation (SF) history of a galactic region can be derived from the colour-magnitude diagram (CMD) of its resolved stars.
Michele Cignoni, Monica Tosi
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High Proper Motion Stars. III. Radial Velocities of 24 Late-Type Dwarfs
The Astronomical Journal, 1998 We report 27 radial velocity measurements for 24 stars, all with annual proper motions larger than 1''. For 17 of these, no velocities have previously been published. We identify a few stars that may be spectroscopic binaries and a sdK star of spectacularly high space velocity.
P. C. Dawson, M. M. De Robertis
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