相关论文: Determining the Age of the Kepler Open Cluster NGC…
We have used 605 days of photometric data from the Kepler spacecraft to study KIC 6614501, a close binary system with an orbital period of 0.15749747(25) days (3.779939 hours), that consists of a low-mass subdwarf B (sdB) star and a white…
The {\emph{Kepler}} space telescope has provided exquisite data to perform asteroseismic analysis on evolved star ensembles. Studying star clusters offers significant insight into stellar evolution and structure, due to having a large…
We present the first detailed analysis of the detached eclipsing binary V15 in the super-metal rich open cluster NGC 6253. We obtain the following absolute parameters: M_p=1.303+-0.006 Msun, R_p=1.71+-0.03 Rsun, L_p=2.98+-0.10 Lsun for the…
We present a photometric and spectroscopic study of the young open cluster NGC 7419, which is know to host a large number of classical Be stars for reasons not well understood. Based on CCD photometric observations of 327 stars in UBV…
We present a determination of precise fundamental physical parameters of twenty detached, double- lined, eclipsing binary stars in the Large Magellanic Cloud (LMC) containing G- or early K-type giant stars. Eleven are new systems, the…
We present 35 new spectroscopic-binary orbits from our extended radial-velocity (RV) survey of the old ($6.4 \pm 0.2$ Gyr) open cluster NGC 188. Using data from the WIYN Open Cluster Study (WOCS) and APOGEE-2, this work nearly doubles the…
NGC 6791 is a well studied open cluster1 that it is so close to us that can be imaged down to very faint luminosities. The main sequence turn-off age (~8 Gyr) and the age derived from the termination of the white dwarf cooling sequence (~6…
We use 2MASS photometry to study colour-magnitude and colour-colour diagrams, structure and mass distribution in the ionizing open cluster NGC\,6611. Reddening variation throughout the cluster region is taken into account followed by…
We analyse the Catalina Real-time Transient Survey light curves of 835 spectroscopically confirmed white dwarf plus main-sequence binaries from the Sloan Digital Sky Survey (SDSS) with g<19, in search of new eclipsing systems. We identify…
We report our spectroscopic monitoring of the detached, grazing, and slightly eccentric 12-day double-lined eclipsing binary EPIC 219568666 in the old nearby open cluster Ruprecht 147. This is the second eclipsing system to be analyzed in…
We have developed a maximum-likelihood procedure to fit theoretical isochrones to the observed cluster color-magnitude diagrams of NGC 6866, an open cluster in the Kepler Spacecraft field of view. The Markov-Chain Monte Carlo algorithm…
We have found a system listed in the Kepler Binary Catalog (3.273 day period; Prsa et al. 2010) that we have determined is comprised of a low-mass, thermally-bloated, hot white dwarf orbiting an A star of about 2.3 solar masses. In this…
In the old, populous, and metal-rich open cluster NGC 6791 we have used deep HST/ACS images to track the white dwarf cooling sequence down to m_F606W~28.5. The white dwarf luminosity function shows a well defined peak at m_F606W~27.4, and a…
High-dispersion spectra of 333 stars in the open cluster NGC 6819, obtained using the HYDRA spectrograph on the WIYN 3.5m telescope, have been analyzed to determine the abundances of iron and other metals from lines in the 400 A region…
KIC 7955301 is a hierarchical triple system with eclipse timing and depth variations discovered by the Kepler mission. It is composed of a non-eclipsing primary star at the bottom of the red giant branch on a 209-day orbit with a K/G-type…
We present 98 spectroscopic binary orbits resulting from our ongoing radial-velocity survey of the old (7 Gyr) open cluster NGC 188. All but 13 are high-probability cluster members based on both radial-velocity and proper-motion membership…
Three new photometric CCD-based datasets are presented for NGC~6791. They consist of deep UBV photometry (to $V_{lim} =24$, $B_{lim}=24$, $U_{lim} = 23$) of the central parts of the cluster and of selected fields around it, and of…
We report the analysis of a binary blue straggler in NGC 6752 with a short orbital period of 0.315 d and a W UMA-type light curve. We use photometric data spanning 13 years to place limits on the mass ratio (0.15<q<0.35), luminosity ratio…
In this study we identify 11 Kepler systems (KIC 5255552, 5653126, 5731312, 7670617, 7821010, 8023317, 10268809, 10296163, 11519226, 11558882 and 12356914) with a "flip-flop" effect in the eclipse timing variations O-C diagrams of the…
NGC 6397 is one of the most interesting, well observed and theoretically studied globular clusters. The existing wealth of observations allows us to study the reliability of the theoretical white dwarf cooling sequences of low metallicity…