903 datasets found

We present a novel method for estimating lower-limit surface gravities (logg) of Kepler targets whose data do not allow the detection of solar-like oscillations. The method is...

We performed low-resolution (R~40) near-infrared (0.9-2.4{mu}m) multi-object spectroscopy of 240 isolated point sources having apparent H-band magnitudes between 9 and 18 in the...

A large fraction of cool, low-mass stars exhibit brightness fluctuations that arise from a combination of convective granulation, acoustic oscillations, magnetic activity, and...

The rotation-mass-age relationship offers a promising avenue for measuring the ages of field stars, assuming the attendant uncertainties to this technique can be well...

Stellar rotation is a strong function of both mass and evolutionary state. Missions such as Kepler and CoRoT provide tens of thousands of rotation periods, drawn from stellar...

We present near- and mid-infrared photometry and spectroscopy from PAIRITEL, IRTF, and Spitzer of a metallicity-unbiased sample of 117 cool, hydrogen-atmosphere white dwarfs...

Oxygen abundances of 67 dwarf stars in the metallicity range -1.6<[Fe/H]<-0.4 are derived from a non-LTE analysis of the 777nm OI triplet lines. These stars have precise...

We present results from the first application of the Grid of Red Supergiant and Asymptotic Giant Branch ModelS (GRAMS) model grid to the entire evolved stellar population of the...

We present Herschel PACS photometry of 17 B- to M-type stars in the 30Myr old Tucana-Horologium Association. This work is part of the Herschel Open Time Key Programme "Gas in...

We report stellar parameters for late-K and M-type planet-candidate host stars announced by the Kepler Mission. We obtained medium-resolution, K-band spectra of 84 cool...

Asteroseismology with the Kepler space telescope is providing not only an improved characterization of exoplanets and their host stars, but also a new window on stellar...

We present K-band spectra for 133 nearby (d < 33 pc) M dwarfs, including 18 M dwarfs with reliable metallicity estimates (as inferred from an FGK type companion), 11 M dwarf...

We present a new census of the Orion Nebula Cluster over a large field of view (>~30'x30'), significantly increasing the known population of stellar and substellar cluster...

We present the results of a search for unusually rapidly rotating giant stars in a large sample of K giants (~1300 stars) that had been spectroscopically monitored as potential...

We present initial results on some of the properties of open clusters NGC 6791 and NGC 6819 derived from asteroseismic data obtained by NASA's Kepler mission. In addition to...

Two recent observing campaigns provide us with moderate dispersion spectra of more than 230 cluster and 370 field B stars. Combining them and the spectra of the B stars from our...

A search for young substellar objects in the {rho} Oph cloud core region has been made with the aid of multiband profile-fitting point-source photometry of the deep-integration...

Previous surveys in a few metal-poor globular clusters (GCs) showed that the determination of abundances for Li and proton-capture elements offers a key tool to address the...

We present {lambda}/{Delta}{lambda}=550-1200 near-infrared H and K spectra for a magnitude-limited sample of 79 asymptotic giant branch and cool supergiant stars in the central...

To understand the formation of stellar groups, one must first document carefully the birth pattern within real clusters and associations. In this study of Taurus-Auriga, we...