Results 21 to 30 of about 43,149 (291)

Improvements to Stellar Structure Models, Based on a Grid of 3D Convection Simulations. I. $T(\tau)$-Relations [PDF]

, 2014
Relations between temperature, T, and optical depth, tau, are often used for describing the photospheric transition from optically thick to optically thin in stellar structure models.
Asplund, Martin, Christensen-Dalsgaard, Jørgen, Nordlund, Åke, Stein, Robert F., Trampedach, Regner   +4 more
core   +1 more source

Spectral Evolution Models for the Next Decade [PDF]

, 2009
Spectral evolution models are a widely used tool for determining the stellar content of galaxies. I provide a review of the latest developments in stellar atmosphere and evolution models, with an emphasis on massive stars.
Claus Leitherer, Gustafsson, Kroupa, Meynet, Pauldrach, Puls, Puls, Smith   +7 more
core   +1 more source

2D MODELLING OF THE GAS FLOW STRUCTURE IN THE SYMBIOTIC STAR Z ANDROMEDAE

Odessa Astronomical Publications, 2017
The 2D gasdynamical simulations of gas structure in the symbiotic star Z And have been carried out for different stellar wind regimes. Since the mechanisms of gas acceleration in stellar atmospheres are not well studied, the parametric representation of ...
E. Yu. Kilpio
doaj   +1 more source

Dust cloud evolution in sub-stellar atmospheres via plasma deposition and plasma sputtering [PDF]

, 2017
Context. In contemporary sub-stellar model atmospheres, dust growth occurs through neutral gas-phase surface chemistry. Recently, there has been a growing body of theoretical and observational evidence suggesting that ionisation processes can also occur.
Diver, D. A., Stark, C. R.
core   +4 more sources

Statistical Signatures of Nanoflare Activity. III. Evidence of Enhanced Nanoflaring Rates in Fully Convective stars as Observed by the NGTS

The Astrophysical Journal, 2023
Previous examinations of fully convective M-dwarf stars have highlighted enhanced rates of nanoflare activity on these distant stellar sources. However, the specific role the convective boundary, which is believed to be present for spectral types earlier
S. D. T. Grant, D. B. Jess, C. J. Dillon, M. Mathioudakis, C. A. Watson, J. A. G. Jackman, D. G. Jackson, P. J. Wheatley, M. R. Goad, S. L. Casewell, D. R. Anderson, M. R. Burleigh, R. G. West, J. I. Vines   +13 more
doaj   +1 more source

Using limb darkening to measure fundamental parameters of stars

, 2012
Context. Limb darkening is an important tool for understanding stellar atmospheres, but most observations measuring limb darkening assume various parameterizations that yield no significant information about the structure of stellar atmospheres. Aims. We
An, Claret, Claret, Fields, H. R. Neilson, Haubois, Heyrovský, Heyrovský, J. B. Lester, Knutson, Lee, Lester, Mérand, Neilson, Neilson, Ohnaka, Popper, Wade, Wittkowski, Wittkowski, Wittkowski, Zub   +21 more
core   +1 more source

Solar and stellar photospheric abundances

Living Reviews in Solar Physics, 2016
The determination of photospheric abundances in late-type stars from spectroscopic observations is a well-established field, built on solid theoretical foundations.
Carlos Allende Prieto
doaj   +1 more source

The True Nature of the Brightest Local Triple Stellar Candidates within 100 pc in the Galaxy

The Astronomical Journal, 2023
We present a study of a sample of bright ( V ≤ 10 mag) and close ( d ≤ 100 pc) triple–stellar system candidates in the galaxy, consisting of eight systems in total.
Z. T. Yousef, A. Annuar, Mashhoor A. Al-Wardat, N. S. A. Hamid   +3 more
doaj   +1 more source

Three-dimensional simulations of near-surface convection in main-sequence stars - II. Properties of granulation and spectral lines

, 2013
The atmospheres of cool main-sequence stars are structured by convective flows from the convective envelope that penetrate the optically thin layers and lead to structuring of the stellar atmospheres analogous to solar granulation.
Beeck, Benjamin, Cameron, Robert H., Reiners, Ansgar, Schüssler, Manfred   +3 more
core   +2 more sources

Stellar abundance analyses in the light of 3D hydrodynamical model atmospheres [PDF]

, 2003
I describe recent progress in terms of 3D hydrodynamical model atmospheres and 3D line formation and their applications to stellar abundance analyses of late-type stars.
Asplund, Martin
core   +2 more sources