- ID:
- ivo://CDS.VizieR/J/ApJ/759/19
- Title:
- Precise radial velocities of {rho}^1^ Cancri
- Short Name:
- J/ApJ/759/19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a mass determination for the transiting super-Earth {rho}^1^ Cancri e based on nearly 700 precise radial velocity (RV) measurements. This extensive RV data set consists of data collected by the McDonald Observatory planet search and published data from Lick and Keck observatories. We obtained 212 RV measurements with the Tull Coud\'e Spectrograph at the Harlan J. Smith 2.7m Telescope and combined them with a new Doppler reduction of the 131 spectra that we have taken in 2003-2004 with the High-Resolution Spectrograph (HRS) at the Hobby-Eberly Telescope for the original discovery of {rho}^1^ Cancri e. Using this large data set we obtain a five-planet Keplerian orbital solution for the system and measure an RV semi-amplitude of K=6.29+/-0.21m/s for {rho}^1^ Cnc e and determine a mass of 8.37+/-0.38M_{oplus}_. The uncertainty in mass is thus less than 5%. This planet was previously found to transit its parent star, which allowed them to estimate its radius. Combined with the latest radius estimate from Gillon et al. (Cat. J/A+A/539/A28), we obtain a mean density of {rho}=4.50+/-0.20g/cm3. The location of {rho}^1^ Cnc e in the mass-radius diagram suggests that the planet contains a significant amount of volatiles, possibly a water-rich envelope surrounding a rocky core.
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- ID:
- ivo://CDS.VizieR/J/AJ/156/142
- Title:
- Precision cluster abund. for APOGEE using SDSS DR14
- Short Name:
- J/AJ/156/142
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Open Cluster Chemical Abundances and Mapping (OCCAM) survey aims to produce a comprehensive, uniform, infrared-based spectroscopic data set for hundreds of open clusters, and to constrain key Galactic dynamical and chemical parameters from this sample. This second contribution from the OCCAM survey presents analysis of 259 member stars with [Fe/H] determinations in 19 open clusters, using Sloan Digital Sky Survey Data Release 14 (SDSS/DR14) data from the Apache Point Observatory Galactic Evolution Experiment and ESA Gaia. This analysis, which includes clusters with R_GC_ ranging from 7 to 13 kpc, measures an [Fe/H] gradient of -0.061+/-0.004 dex/kpc. We also confirm evidence of a significant positive gradient in the {alpha}-elements ([O/Fe], [Mg/Fe], and [Si/Fe]) and present evidence for a significant negative gradient in iron-peak elements ([Mn/Fe] and [Ni/Fe]).
- ID:
- ivo://CDS.VizieR/J/A+A/530/A28
- Title:
- Priority targets for the MUCHFUSS project
- Short Name:
- J/A+A/530/A28
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The project Massive Unseen Companions to Hot Faint Underluminous Stars from SDSS (MUCHFUSS) aims at finding sdBs with compact companions like supermassive white dwarfs (M>1.0M_{sun}_), neutron stars or black holes. The existence of such systems is predicted by binary evolution theory and recent discoveries indicate that they are likely to exist in our Galaxy. A determination of the orbital parameters is sufficient to put a lower limit on the companion mass by calculating the binary mass function. If this lower limit exceeds the Chandrasekhar mass and no sign of a companion is visible in the spectra, the existence of a massive compact companion is proven without the need for any additional assumptions. We identified about 1100 hot subdwarf stars from the SDSS by colour selection and visual inspection of their spectra. Stars with high velocities have been reobserved and individual SDSS spectra have been analysed. In total 127 radial velocity variable subdwarfs have been discovered. Binaries with high RV shifts and binaries with moderate shifts within short timespans have the highest probability of hosting massive compact companions. Atmospheric parameters of 69 hot subdwarfs in these binary systems have been determined by means of a quantitative spectral analysis. The atmospheric parameter distribution of the selected sample does not differ from previously studied samples of hot subdwarfs. The systems are considered the best candidates to search for massive compact companions by follow-up time resolved spectroscopy.
- ID:
- ivo://CDS.VizieR/J/AN/338/686
- Title:
- Pristine survey II. Bright stars abundances
- Short Name:
- J/AN/338/686
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Extremely metal-poor (EMP) stars are old objects formed in the first Gyr of the Universe. They are rare and, to select them the most successful strategy has been to build on large and low-resolution spectroscopic surveys. The combination of narrow- and broad-band photometry provides a powerful and cheaper alternative to select metal-poor stars. The ongoing Pristine Survey is adopting this strategy, conducting photometry with the Canada France Hawaii Telescope MegaCam wide-field imager and a narrow-band filter centered at 395.2nm on the Ca II-H and -K lines. In this paper, we present the results of the spectroscopic follow-up conducted on a sample of 26 stars at the bright end of the magnitude range of the Survey (g<=15), using FEROS at the MPG/ESO 2.2-m telescope (manufactured by Zeiss, Oberkochen, Germany). From our chemical investigation on the sample, we conclude that this magnitude range is too bright to use the Sloan Digital Sky Survey (SDSS) gri bands, which are typically saturated. Instead, the Pristine photometry can be usefully combined with the AAVSO Photometric All Sky Survey (APASS) gri photometry to provide reliable metallicity estimates. Data from FEROS.
- ID:
- ivo://CDS.VizieR/J/A+A/478/197
- Title:
- Procyon (alpha CMi) radial velocities
- Short Name:
- J/A+A/478/197
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The data represent report a 9-night asteroseismic observation program conducted in January 2007 with the new spectrometer SOPHIE at the OHP 193-cm telescope, on the F5 IV-V target Procyon A. This first asteroseismic program with SOPHIE was intended to test the performance of the instrument with a bright but demanding asteroseismic target and was part of a multisite network. The SOPHIE spectra have been reduced with the data reduction software provided by OHP.
- ID:
- ivo://CDS.VizieR/J/AJ/142/71
- Title:
- Proper motions and photometry of stars near NGC7380
- Short Name:
- J/AJ/142/71
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present proper motions, radial velocities, and a photometric study of the Galactic open cluster NGC 7380, which is associated with prominent emission nebulosity and dark molecular clouds. On the basis of the sample of highly probable member stars, the star cluster is found to be at a distance of 2.6+/-0.4kpc, has an age of around 4Myr, and a physical size of ~6pc across with a tidal structure. The binary O-type star DH Cep is a member of the cluster in its late stage of clearing the surrounding material, and may have triggered the ongoing star formation in neighboring molecular clouds which harbor young stars that are coeval and comoving with, but not gravitationally bound by, the star cluster.
- ID:
- ivo://CDS.VizieR/J/ApJ/602/264
- Title:
- Proper motions and radial velocities in M15
- Short Name:
- J/ApJ/602/264
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Newly determined high-precision relative proper motions determined from the Hubble Space Telescope Wide Field Planetary Camera 2 are used along with radial velocity measurements to determine the dynamical distance to the globular cluster M15. A comparison of the proper motion and radial velocity dispersions from a sample of 237 stars, located at an average radial distance of about 10" from the cluster center, yields a cluster distance of 9.98+/-0.47kpc. This distance agrees to within the stated errors to other distance estimates but places this object about 5% closer than the currently adopted value of 10.4kpc. Using this new distance, we estimate that RR Lyrae stars having [Fe/H]=-2.15 have a value of Mv(RR)=0.51+/-0.11. We also estimate that M15 has an age of about 13.2Gyr, which places it among the oldest of the Galactic globular clusters. From a comparison of the observed velocity dispersion with results from recent N-body calculations, we derive a total cluster mass for M15 of M_C_=4.5x10^5^M_{sun}_.
- ID:
- ivo://CDS.VizieR/J/A+A/397/899
- Title:
- Proper motions of field HB stars
- Short Name:
- J/A+A/397/899
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We set new limits on the mass of the Milky Way, making use of the latest kinematic information for Galactic satellites and halo objects. Our sample consists of 11 satellite galaxies, 137 globular clusters, and 413 field horizontal-branch (FHB) stars up to distances of 10kpc from the Sun. Roughly half of the objects in this sample have measured proper motions, permitting the use of their full space motions in our analysis. The field horizontal branch stars presented in table1 was created from the list of Wilhelm 1999 (J/AJ/117/2329) as the source of magnitudes, radial velocities and [Fe/H]; the proper motions were extracted from one or more proper-motion catalogs: STARNET Catalog (Roeser 1996), Yale-San Juan Southern Proper Motion Catalog (SPM 2.0: Platais et al. 1998, Cat. I/283), Lick Northern Proper Motion Catalog (NPM1: Klemola et al. 1994, Cat. I/199), and TYCHO-2 Catalog (Hog et al. 2000, Cat. I/259).
- ID:
- ivo://CDS.VizieR/J/AJ/119/2866
- Title:
- Proper motions of metal-poor stars
- Short Name:
- J/AJ/119/2866
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a revised catalog of 2106 Galactic stars, selected without kinematic bias and with available radial velocities, distance estimates, and metal abundances in the range -4.0<=[Fe/H]<=0.0. This update of the 1995 Beers & Sommer-Larsen catalog (Cat. <J/ApJS/96/175>) includes newly derived homogeneous photometric distance estimates, revised radial velocities for a number of stars with recently obtained high-resolution spectra, and refined metallicities for stars originally identified in the HK objective-prism survey (which account for nearly half of the catalog) based on a recent recalibration. A subset of 1258 stars in this catalog have available proper motions based on measurements obtained with the Hipparcos astrometry satellite or taken from the updated Astrographic Catalogue (second epoch positions from either the Hubble Space Telescope Guide Star Catalog or the Tycho Catalogue), the Yale/San Juan Southern Proper Motion Catalog 2.0, and the Lick Northern Proper Motion Catalog. Our present catalog includes 388 RR Lyrae variables (182 of which are newly added), 38 variables of other types, and 1680 nonvariables, with distances in the range 0.1 to 40kpc.
- ID:
- ivo://CDS.VizieR/J/MNRAS/484/2832
- Title:
- Proper motions of Milky Way globular clusters
- Short Name:
- J/MNRAS/484/2832
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use Gaia Data Release 2 to determine the mean proper motions for 150 Milky Way globular clusters (almost the entire known population), with a typical uncertainty of 0.05mas/yr limited mainly by systematic errors. Combining them with distance and line-of-sight velocity measurements from the literature, we analyse the distribution of globular clusters in the 6D phase space, using both position/velocity and action/angle coordinates. The population of clusters in the central 10kpc has a mean rotational velocity reaching 50-80km/s, and a nearly isotropic velocity dispersion 100-120km/s, while in the outer galaxy, the cluster orbits are strongly radially anisotropic. We confirm a concentration of clusters at high radial action in the outer region of the Galaxy. Finally, we explore a range of equilibrium distribution function-based models for the entire globular cluster system, and the information they provide about the potential of the Milky Way. The dynamics of clusters is best described by models with the circular velocity between 10 and 50kpc staying in the range 210-240km/s.
