Results 11 to 20 of about 50,982 (241)
Reionization and the Abundance of Galactic Satellites [PDF]
The Astrophysical Journal, 2000 One of the main challenges facing standard hierarchical structure formation models is that the predicted abundance of galactic subhalos with circular velocities of 10-30 km/s is an order of magnitude higher than the number of satellites actually observed within the Local Group.
James S. Bullock +2 more
openalex +5 more sources
Fluorine Abundances of Galactic Low-Metallicity Giants [PDF]
The Astrophysical Journal, 2013 With abundances and 2{\sigma} upper limits of fluorine (F) in seven metal-poor field giants, nucleosynthesis of stellar F at low metallicity is discussed.
Caffau, E. +4 more
core +5 more sources
The Galactic Thick Disk Stellar Abundances [PDF]
The Astronomical Journal, 2000 We present first results from a program to measure the chemical abundances of a large (N>30) sample of thick disk stars with the principal goal of investigating the formation history of the Galactic thick disk. Our analysis confirms previous studies of O and Mg in the thick disk stars which reported enhancements in excess of the thin disk population.
J. X. Prochaska +4 more
+6 more sources
Sulfur abundances in the Galactic bulge and disk [PDF]
Astronomy & Astrophysics, 2021 Context. The measurement of α-element abundances provides a powerful tool for placing constraints on the chemical evolution and star formation history of galaxies. The majority of studies on the α-element sulfur (S) are focused on local stars, making S behavior in other environments an astronomical topic that is yet to be explored in detail. Aims.
Lucertini, Francesca +4 more
openaire +8 more sources
Sulphur abundance in Galactic stars [PDF]
Astronomy & Astrophysics, 2005 accepted by A& ...
Caffau, Elisabetta +5 more
openaire +6 more sources
Fluorine Abundances in the Galactic Disk [PDF]
The Astrophysical Journal, 2019 Abstract The chemical evolution of fluorine is investigated in a sample of Milky Way red giant stars that span a significant range in metallicity from [Fe/H] ∼ −1.3 to 0.0 dex. Fluorine abundances are derived from vibration-rotation lines of HF in high-resolution infrared spectra near 2.335 μm.
Carlos Abia +8 more
openaire +3 more sources
ABUNDANCES OF GALACTIC ANTICENTER PLANETARY NEBULAE AND THE OXYGEN ABUNDANCE GRADIENT IN THE GALACTIC DISK [PDF]
The Astrophysical Journal, 2010 Accepted for publication in the Astrophysical Journal; 42 pages including 5 ...
J. B. Milingo +9 more
openaire +3 more sources
Phosphorus Abundances in the Hyades and Galactic Disk [PDF]
The Astronomical Journal, 2019 Abstract We have measured phosphorus abundances in nine disk stars between −1 < [Fe/H] < –0.5 and in 12 members of the Hyades open cluster using two P I lines at 1.06 μm. High-resolution infrared spectra were obtained using Phoenix on Gemini South and abundances were determined by comparing synthetic spectra to the observations ...
Z. G. Maas +2 more
openaire +4 more sources
The Galactic Oxygen Abundance Gradient [PDF]
The Astrophysical Journal, 1997 We have previously published medium- to high-resolution spectroscopic observations of early B-type main-sequence objects, lying in 18 young, stellar clusters and associations or the general disk population, over galactocentric distances 6 Rg 18 kpc. Using a homogeneous subset of stars with similar atmospheric parameters, we have reanalyzed the O II ...
Smartt, Stephen J. +1 more
openaire +1 more source
Abundances in the Galactic Center [PDF]
Symposium - International Astronomical Union, 1989 Abundance measurements in the Galactic Center (GC) probe material with a nucleosynthetic history unique in our Galaxy. The measurements are of two types: probing interstellar and stellar material. Measurements of gas-phase abundances are mostly toward SgrB2 and SgrA.
openaire +2 more sources