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Galactic evolution of sulphur as traced by globular clusters
(EDP SCIENCES S A, 2015)
Context. Sulphur is an important volatile a element, but its role in the Galactic chemical evolution is still uncertain, and more observations constraining the sulphur abundance in stellar photospheres are required.
DISENTANGLING THE VIRGO OVERDENSITY WITH RR LYRAE STARS
(IOP PUBLISHING LTD, 2016)
We use a combination of spatial distribution and radial velocity to search for halo substructures in a sample of 412 RR Lyrae stars (RRLSs) that covers a. region of similar to 525 square degrees. of the Virgo overdensity ...
Chronography of the Milky Way's Halo System with Field Blue Horizontal-branch Stars
(Iop Publishing, 2015-11-01)
In a pioneering effort, Preston et al. reported that the colors of bluehorizontal-branch (BHB) stars in the halo of the Galaxy shift withdistance, from regions near the Galactic center to about 12 kpc away,and interpreted ...
A SEARCH FOR FIELD HORIZONTAL-BRANCH STARS NEAR THE SOUTH GALACTIC POLE
(IOP PUBLISHING LTD, 2010)
Searches for field horizontal-branch (FHB) stars in the halo of the Galaxy in the past have been carried out by several techniques, such as objective-prism surveys and visual or infrared photometric surveys. By choosing ...
[O/Fe] ESTIMATES FOR CARBON-ENHANCED METAL-POOR STARS FROM NEAR-INFRARED SPECTROSCOPY
(IOP PUBLISHING LTD, 2011)
We report on oxygen abundances determined from medium-resolution near-infrared spectroscopy for a sample of 57 carbon-enhanced metal-poor (CEMP) stars selected from the Hamburg/ESO Survey. The majority of our program stars ...
Origin of the heavy elements in HD 140283 Measurement of europium abundance
(EDP SCIENCES S ALES ULIS CEDEX A, 2012-12)
Context. HD 140283 is a nearby (V = 7.7) subgiant metal-poor star, extensively analysed in the literature. Although many spectra have been obtained for this star, none showed a signal-to-noise (S/N) ratio high enough to ...
Origin of the heavy elements in HD 140283: measurement of europium abundance
(Les Ulis, 2014-03-13)
Context. HD140283 is a nearby (V = 7:7) subgiant metal-poor star, extensively analysed in the literature. Although many spectra have
been obtained for this star, none showed a signal-to-noise (S/N) ratio high enough to ...