Results 101 to 110 of about 146,288 (166)
The California Legacy Survey. V. Chromospheric Activity Cycles in Main-sequence Stars
The Astrophysical Journal Supplement SeriesWe present optical spectroscopy of 710 solar neighborhood stars collected over 20 years to catalog chromospheric activity and search for stellar activity cycles.
Howard Isaacson +33 more
doaj +1 more source
Magnetic reconnection in partially ionized plasmas. [PDF]
Proc Math Phys Eng Sci, 2020 Ni L, Ji H, Murphy NA, Jara-Almonte J.
europepmc +1 more source
The Astrophysical JournalLow-mass (≲1.2 M _⊙ ) main-sequence stars lose angular momentum over time, leading to a decrease in their magnetic activity. The details of this rotation–activity relation remain poorly understood, however.
Alejandro Núñez +8 more
doaj +1 more source
Crowning the Queen: Membership, Age, Rotation, and Activity for the Open Cluster Coma Berenices
The Astrophysical JournalDespite being only 85 pc away, the open cluster Coma Berenices (Coma Ber) has not been extensively studied. This is due in part to its sparseness and low proper motion, which together made Coma Ber’s membership challenging to establish.
M. A. Agüeros +10 more
doaj +1 more source
Exploration of the Outer Envelope of the K-giant Star Beta Cet
The Astrophysical JournalInvestigating the atmospheres of giants and supergiants is critical to expanding our knowledge of stellar life cycles, galaxy formation, and the origin of material that forms exoplanets.
Krister E. Nielsen +2 more
doaj +1 more source
Red Supergiant Mass Loss and Mass-Loss Rates
GalaxiesThis review discusses the causes, nature, importance and observational evidence of mass loss by red supergiants. It arrives at the perception that mass loss finds its origin in the gravity which makes the star a star in the first place, and is a ...
Jacco Th. van Loon
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Role of Nonthermal Processes in the Quiescent and Active Millimeter Spectrum of a Young M Dwarf
The Astrophysical JournalMillimeter (mm) emission from F-M dwarfs (cool stars) primarily traces chromospheric activity, with thermal emission thought to dominate in quiescence. Despite the high chromospheric activity, the quiescent mm spectral fluence (mm- S ( ν )) of young (1 ...
Atul Mohan +5 more
doaj +1 more source
Betelgeuse, the Prototypical Red Supergiant
GalaxiesThe behavior of the bright red supergiant, Betelgeuse, is described with results principally from the past 6 years. The review includes imaging, photometry, and spectroscopy to record the Great Dimming of 2019–2020.
Andrea K. Dupree, Miguel Montargès
doaj +1 more source
87th Annual Meeting of the Meteoritical Society 2025: Abstracts
Meteoritics &Planetary Science, Volume 60, Issue S1, Page 30-350, August 2025.
wiley +1 more source
FUMES. IV. Optical and Far-ultraviolet Spectra of a Flare on the M Dwarf GJ 4334
The Astronomical JournalOn 2017 September 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 Å) and the Dual Imaging Spectrograph mounted on the 3.5 m telescope at
Girish M. Duvvuri +7 more
doaj +1 more source