100 datasets found

High-velocity halo stars provide important information about the properties of the extreme Galactic halo. The study of Population II unbound and bound stars enables us better...

We use 12530 photometrically-selected BHB stars from Sloan Digital Sky Survey DR7 to estimate, the total extinction of the Milky Way in high Galactic latitude, RV and AV in each...

Period study of 321 fundamental mode RR Lyrae type stars (RRab), which had appropriate data in ASAS and SuperWASP surveys, was performed to complement and extend the list of...

We obtained high-resolution spectra for 94 candidate stars belonging to the HB of M 22 with FLAMES. Previous works have indicated that this cluster has split subgiant (SGB) and...

NGC 288 is a globular cluster with a well-developed blue horizontal branch covering the u-jump that indicates the onset of diffusion. It is therefore well suited to study the...

We used FLAMES+GIRAFFE (Medusa mode) at the VLT to obtain moderately high resolution spectra for 30 red horizontal branch (RHB) stars, 4 RR Lyrae variables, and 17 blue...

We present the results of an extensive survey for rapid pulsators among Extreme Horizontal Branch (EHB) stars in {omega} Cen. The observations performed consist of nearly 100...

Recent statistical studies prove that the percentage of RR Lyrae pulsators that are located in binaries or multiple stellar systems is considerably lower than might be expected....

Libraries of stellar spectra find many uses in astrophysics, from photometric calibration to stellar population synthesis. We present low resolution spectra of 40 stars from 0.2...

Homogeneous investigations of red giant stars in open clusters contribute to studies of internal evolutionary mixing processes inside stars, which are reflected in abundances of...

The presence of extreme horizontal branch (EHB) and blue hook stars in some Galactic globular clusters (GGCs) constitutes one of the remaining mysteries of stellar evolution....

We recently found the globular cluster (GC) EXT8 in M31 to have an extremely low metallicity of [Fe/H]=-2.91+/-0.04 using high-resolution spectroscopy. Here we present a...

Blue horizontal-branch stars evolve from low-mass stars that have completed their main-sequence lifetimes and undergone a helium flash at the end of their red-giant phase. As...

Lithium and the carbon isotope ratio ^12^C/^13^C can change during the red giant branch as a result of extra-mixing. This is associated usually with thermohaline mixing acting...

Additional low-amplitude signals are observed in many RR Lyrae stars, beside the pulsations in radial modes. The most common ones are short-period signals forming a period ratio...

By using a large sample of fundamental mode RR Lyrae stars with published spectroscopic iron abundances and gravities, we point out the importance of correcting these abundances...

Stars that are found on the blue horizontal-branch (BHB) evolved from low-mass stars that have completed their core hydrogen-burning main sequence (MS) stage and undergone the...

We used Legacy Survey photometric data to probe the stellar halo in multiple directions of the sky using a probabilistic methodology to identify Blue Horizontal Branch (BHB)...

The metal-rich ([M/H]=-0.48) bulge globular cluster NGC 6388 displays a blue horizontal branch (HB). Helium enrichment, which is correlated with changes seen among other light...

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