Results 11 to 20 of about 11,182,421 (303)

The stochastic enrichment of Population II stars [PDF]

Monthly Notices of the Royal Astronomical Society, 2020
ABSTRACT We investigate the intrinsic scatter in the chemical abundances of a sample of metal-poor ([Fe/H] < −2.5) Milky Way halo stars. We draw our sample from four historic surveys and focus our attention on the stellar Mg, Ca, Ni, and Fe abundances.
Louise Welsh, Ryan Cooke, Michele Fumagalli   +2 more
openaire   +6 more sources

CRITICAL METALLICITY FOR POPULATION II STARS

Odessa Astronomical Publications, 2008
We present simple arguments about metallicity of transition from first stellar generation (population III) to the second one. We consider the efficiency of fragmentation in gas induced by thermal instability in cold gas layers and filaments (T < 104 K ...
E. O. Vasiliev, Yu. A. Shchekinov
doaj   +3 more sources

Radial velocities of Population II stars. II

Open Astronomy, 1999
Bartkevičius A., Sperauskas J.
doaj   +2 more sources

The Possible Signs of Hydrogen and Helium Accretion from Interstellar Medium on the Atmospheres of F-K Giants in the Local Region of the Galaxy [PDF]

Journal of Astronomy and Space Sciences, 2021
The dependencies of the chemical element abundances in stellar atmospheres with respect to solar abundances on the second ionization potentials of the same elements were investigated using the published stellar abundance patterns for 1,149 G and K ...
Alexander Yushchenko, Seunghyun Kim, Yeuncheol Jeong, Aizat Demessinova, Volodymyr Yushchenko, Dmytry Doikov, Vira Gopka, Kyung Sook Jeong, Pakakaew Rittipruk   +8 more
doaj   +1 more source

Catalogues of field Population II stars

Open Astronomy, 1994
Bartkevičius A.
doaj   +2 more sources

Massive binary black holes from Population II and III stars [PDF]

, 2023
Population III stars, born from the primordial gas in the Universe, lose a negligible fraction of their mass via stellar winds and possibly follow a top-heavy mass function.
Ralf S Klessen, Giuliano Iorio, Mapelli, Michela, Guglielmo Costa, Santoliquido, Filippo, Iorio, Giuliano, Filippo Santoliquido, Michela Mapelli, Alessandro Bressan, Escobar, Gastón J., Costa, Guglielmo, Gastón J Escobar, Bressan, Alessandro, Klessen, Ralf S, Escobar, Gastón J, Klessen, Ralf S.   +15 more
core   +1 more source

Radial Velocities of Population II Stars. I.

Open Astronomy, 1992
Bartkevičius A., Sperauskas J., Rastorguev A. S., Tokovinin A. A.   +3 more
doaj   +2 more sources

Anomalous Cepheids discovered in a sample of galactic short period Type II Cepheids [PDF]

Serbian Astronomical Journal, 2018
We revisited the short period Type II Cepheids (T2Cs), called the BL Herculis (BLHs), in the Galactic Field to derive a homogeneous analysis of their Fourier parameters.
Jurković M.I.
doaj   +1 more source

Hypervelocity Stars. II. The Bound Population [PDF]

The Astrophysical Journal, 2007
Hypervelocity stars (HVSs) are stars ejected completely out of the Milky Way by three-body interactions with the massive black hole in the Galactic center. We describe 643 new spectroscopic observations from our targeted survey for HVSs. We find a significant (3.5 sigma) excess of B-type stars with large velocities +27510 kpc that are most plausibly ...
Brown, Warren R., Geller, Margaret J., Kenyon, Scott J., Kurtz, Michael J., Bromley, Benjamin C.   +4 more
openaire   +2 more sources

Lithium 6104 Å in Population II stars [PDF]

Astronomy & Astrophysics, 2002
We have obtained echelle spectroscopy of 14 Population II objects selected from those previously observed by Bonifacio & Molaro (1997). For one object, HD 140283, we obtained exquisite data with the High Dispersion Spectrograph on the Subaru Telescope, with S/N exceeding 1000 per 0.018A pixel.
Ford, A., Jeffries, R.D., Smalley, B., Ryan, S.G., Aoki, W., Kawanomoto, S., James, D.J., Barnes, J.R.   +7 more
openaire   +3 more sources