Results 21 to 30 of about 40,670 (264)

The Theory of Winds in Early Type Stars [PDF]

International Astronomical Union Colloquium, 1981
I assume that the purpose of this review of the theory of winds from early type stars is to summarize the way in which the mass loss rate of a star may be included in a calculation of stellar evolution. Let me summarize my conclusions. It is not possible. One can only use estimates of mass loss rates obtained from the observations.
openaire   +1 more source

Binary stars and the UVX in early-type galaxies [PDF]

Monthly Notices of the Royal Astronomical Society, 2014
9 pages, 2 figures.
Hernández-Pérez, Fabiola, Bruzual, Gustavo   +1 more
openaire   +2 more sources

Radial velocities of early-type stars [PDF]

Symposium - International Astronomical Union, 1970
With the Fehrenbach objective prism radial velocities of about 700 stars of type B0 to A0 were determined in two fields of the Southern Milky Way (lII = 295° bII = −0.6°; lII = 320° bII = −2.5°), with a mean error of ±20 km s−1. An additional photographic UBV-photometry with plates of the ADH-telescope at Boyden Observatory was accomplished.
openaire   +1 more source

X-ray properties of early-type stars [PDF]

Symposium - International Astronomical Union, 1994
Extensive stellar surveys with the Einstein Observatory (Chlebowski et al., 1989) and with ROSAT have clearly confirmed the presence of stellar X-ray emission over nearly the whole range of the HR diagram. In the ROSAT all-sky survey data approximately 20000 stellar X-ray sources were detected (Schmitt et al., 1992).
Thomas W. Berghöfer, Jürgen H. M. M. Schmitt   +1 more
openaire   +1 more source

New Methods in Modeling of Hot Stellar Atmospheres

Open Astronomy, 2013
In the present study we had three main aims. First to study the possibility of reducing the initial model atmosphere data to short analytical polynomials.
Sapar A., Poolamäe R., Sapar L.
doaj   +1 more source

Evolution of brightness and magnetic features of young solar-type stars – II. The young F8 star HIP 71933 [PDF]

, 2023
The early, active history of our Sun is still not fully understood. Observations of the magnetic fields on active young solar-type stars allow us an insight into the early evolution of our Sun.
Waite, I A, Perugini, G M, Burton, D M, S C Marsden, I A Waite, Hughes, J E, Marsden, S C, J E Hughes, B D Carter, D M Burton, E M Hébrard, Carter, B, Hebrard, E M, G M Perugini   +13 more
core   +1 more source

A New High-Precision Correction Method of Temperature Distribution in Model Stellar Atmospheres

Open Astronomy, 2013
The main features of the temperature correction methods, suggested and used in modeling of plane-parallel stellar atmospheres, are discussed. The main features of the new method are described.
Sapar A., Poolamäe R., Sapar L.
doaj   +1 more source

Post-outburst Evolution of Bona Fide FU Ori-type V2493 Cygnus: A Spectro-photometric Monitoring

The Astrophysical Journal, 2023
We present here the results of 8 yr of our near-simultaneous optical–near-infrared spectro-photometric monitoring of the bona fide FU Ori (FUor)-type candidate V2493 Cygnus (V2493 Cyg) starting from 2013 September to 2021 June.
Arpan Ghosh, Saurabh Sharma, Joe P. Ninan, Devendra K. Ojha, Bhuwan C. Bhatt, D. K. Sahu, Tapas Baug, R. K. Yadav, Puji Irawati, A. S. Gour, Neelam Panwar, Rakesh Pandey, Tirthendu Sinha, Aayushi Verma   +13 more
doaj   +1 more source

CNO abundances in Early Type Be Stars [PDF]

Symposium - International Astronomical Union, 2004
High dispersion spectra in the visible range were obtained for field Be Stars in both hemispheres. As Be Stars form a class of Main Sequence fast rotators, we are intended to test how their chemical composition can be affected by rotation.
Y. Frémat, J. Zorec, R. Levenhagen, N. Leister, A.-M. Hubert, M. Floquet, C. Neiner   +6 more
openaire   +1 more source

A BCool magnetic snapshot survey of solar-type stars [PDF]

, 2014
SVJ acknowledges research funding by the Deutsche Forschungsgemeinschaft (DFG) under grant SFB 963/1, project A16. JM was funded by a fellowship of the Alexander von Humboldt Foundation in Göttingen.
Jeffers, S., Ramirez-Velez, J. C., Reiners, Ansgar, Carter, B.D., Donati, J. -F., Jardine, M., do Nascimento, J.-D., Collaboration, The Bcool, Petit, P., Dintrans, B.D., Ramirez-Vèlez, J., Marsden, S., do Nascimento Jr., J., Dintrans, B., Ramirez-Veles, J.C., Donati, J., Carter, Brad D., Auriere, M., Lignieres, F., Nascimento, J. D. Do, Marsden, S. C., Van Grootel, V., Morin, J., do Nascimento, J.-D., Jr., Bouvier, J., Jeffers, Sandra V., Fares, R., Theado, S., Gastine,, Gastine, Thomas, Morin, Julien, Donati, J.-F., Van Grootel, Valérie, BCool Collaboration, do Nascimento Jr., J.-D., Lanoux, J., Morgenthaler, A., Konstantinova-Antova, R., Reiners, A., Jeffers, S.V., Jeffers, S. V., Catala, C., Gastine, T., do Nascimento, J. -D., Carter, B. D., Marsden, S.C., Carter, B., Collaboration, T.   +47 more
core   +1 more source