Results 81 to 90 of about 334 (164)

Exploration of the Outer Envelope of the K-giant Star Beta Cet

The Astrophysical Journal
Investigating 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, Gioia Rau, Kenneth G. Carpenter   +2 more
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

The Factory and the Beehive. V. Chromospheric and Coronal Activity and Its Dependence on Rotation in Praesepe and the Hyades

The Astrophysical Journal
Low-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, Marcel A. Agüeros, Jason L. Curtis, Kevin R. Covey, Stephanie T. Douglas, Sabine R. Chu, Stanislav DeLaurentiis, Minzhi (Luna) Wang, Jeremy J. Drake   +8 more
doaj   +1 more source

Stellar chromospheric and coronal heating by magnetohydrodynamic waves

The Astrophysical Journal, 1981
An investigation is presented on the way in which the generation of magnetohydrodynamic waves by turbulent motions in stellar convection zones depends on the star's effective temperature, surface gravity, and magnetic field strength. It is shown that the emitted Alfven wave flux (and acoustic slow wave flux in a very strong magnetic field) is in ...
openaire   +1 more source

Role of Nonthermal Processes in the Quiescent and Active Millimeter Spectrum of a Young M Dwarf

The Astrophysical Journal
Millimeter (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, Peter H. Hauschildt, Birgit Fuhrmeister, Surajit Mondal, Vladimir Airapetian, Sven Wedemeyer   +5 more
doaj   +1 more source

Red Supergiant Mass Loss and Mass-Loss Rates

Galaxies
This 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
doaj   +1 more source

Crowning the Queen: Membership, Age, Rotation, and Activity for the Open Cluster Coma Berenices

The Astrophysical Journal
Despite 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, J. L. Curtis, A. Núñez, C. Burhenne, P. Rothstein, B. J. Shaham, K. Singh, P. Bergeron, M. Kilic, K. R. Covey, S. T. Douglas   +10 more
doaj   +1 more source

Betelgeuse, the Prototypical Red Supergiant

Galaxies
The 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

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

Progress in semi-empirical modelling of main-sequence stellar chromospheres [PDF]

, 1996
E. R. Houdebine
openalex   +1 more source