Related papers: M67 Blue Stragglers with High-resolution Infrared …
Within the variety of objects populating stellar clusters, blue straggler stars (BSSs) are among the most puzzling ones. BSSs are commonly found in globular clusters, but they are also known to populate open clusters of the Milky Way. Two…
From high resolution (R = 45,000), high signal-to-noise (S/N > 400) spectra gathered with the Immersion Grating Infrared Spectrograph (IGRINS) in the H and K photometric bands, we have derived elemental abundances of two bright, well-known…
The upper region of the Hertzsprung-Russell diagram is populated by massive stars in a diversity of evolutionary stages, and the classification of these stars is often based on observed characteristics exclusively in the optical spectral…
We present a spectroscopic study at high resolution, R~50,000, of 14 stars located on the main sequence, at the turn-off point and on the early subgiant branch in the cluster M67 in order to investigate its detailed chemical composition,…
Blue Stragglers are stars located in an unexpected region of the color-magnitude diagram of a stellar population, as they appear bluer and more luminous than the stars in the turnoff region. They are ubiquitous, since they have been found…
We test the performance of our analysis technique for integrated-light spectra by applying it to seven well-studied Galactic GCs that span a wide range of metallicities. Integrated-light spectra were obtained by scanning the slit of the…
We present analysis of high-resolution spectra of a sample of stars in the globular cluster M5 (NGC 5904). The sample includes stars from the red giant branch (seven stars), the red horizontal branch (two stars), and the asymptotic giant…
We present the sample for an abundance analysis of 25 members of M71 with luminosities ranging from the red giant branch tip to the upper main sequence. The spectra are of high dispersion and of high precision. We describe the observing…
We have made an asteroseismic analysis of the variable blue stragglers in the open cluster M67. The data set consists of photometric time series from eight sites using nine 0.6-2.1 meter telescopes with a time baseline of 43 days. In two…
Clear identifications of Galactic young stellar clusters farther than a few kpc from the Sun are rare, despite the large number of candidate clusters. We aim to improve the selection of candidate clusters rich in massive stars with a…
In this paper, we present a detailed high-resolution spectroscopic study of post main sequence stars in the Globular Cluster M68. Our sample, which covers a range of 4000 K in $T_{eff}$, and 3.5 dex in $log(g)$, is comprised of members from…
We identify [Rb IV] 1.5973 and [Cd IV] 1.7204 micron emission lines in high-resolution (R=40,000) near-infrared spectra of the planetary nebulae (PNe) NGC 7027 and IC 5117, obtained with the IGRINS spectrometer on the 2.7-m telescope at…
We present nine color CCD intermediate-band spectrophotometry of a two square degree field centered on the old open cluster M67, from 3890$\rm \AA$ to nearly 1$\mu$. These observations are taken as a part of the BATC…
We present high-precision VI photometry of stars from the middle of the giant branch to about 5 magnitudes below the main-sequence turnoff in the globular cluster Palomar 13 based on images obtained with the Keck II 10m telescope. We…
With an aim to examine whether the surface oxygen composition suffers any appreciable change due to evolution-induced mixing of nuclear-processed material in the envelope of red giants, abundance determinations for O/Fe/Ni based on the…
Abundances of C and N are derived from features due to the CH G-band and to the UV CN band measured on high resolution (R ~ 40,000) UVES spectra of more than 40 dwarfs and subgiants in NGC 6397, NGC 6752 and 47 Tuc. Oxygen abundances (or…
The dense central region of NGC 6397 contains three classes of stars whose origins are likely related to stellar interactions: blue stragglers, cataclysmic variables, and probable helium white dwarfs. We summarize results concerning CVs and…
Symbiotic stars (SySt) are binaries composed of a star in the later stages of evolution and a stellar remnant. The enhanced mass-loss from the giant drives interacting mass exchange and makes these systems laboratories for understanding…
We present the iron abundance and abundance ratios for 18 elements with respect to Fe in a sample of stars with a wide range in luminosity from luminous giants to stars near the turnoff in the globular cluster M5. The analyzed spectra,…
We report the first detailed chemical abundances for 5 globular clusters (GCs) in M31 from high-resolution (R ~ 25,000) spectroscopy of their integrated light. These GCs are the first in a larger set of clusters observed as part of an…