- ID:
- ivo://org.gavo.dc/gcns/q/pub
- Title:
- The Gaia eDR3 Catalogue of Nearby Stars GCNS
- Date:
- 06 Feb 2024 09:09:51
- Publisher:
- The GAVO DC team
- Description:
- This is a clean and well characterised catalogue of objects within 100pc of the Sun from the Gaia early third data release. We characterise the catalogue using the full data release, and comparisons to other catalogues in literature and simulations. For all candidates (measured parallax < 8 mas), we calculate a distance probability function using Bayesian procedures and mock catalogues for the prediction of the priors. For each entry using a random forest classifier we attempt to remove sources with spurious astrometric solutions. This results in 331312 objects that should contain at least 92% of stars within 100 pc at spectral type M9. GCNS comes with several auxiliary tables, in particular lists of resolved stellar systems, of known neary stars not found in eDR3 and of candidates of Hyades and ComaBer cluster members.
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- ID:
- ivo://org.gavo.dc/gcns/q/cone
- Title:
- The Gaia eDR3 Catalogue of Nearby Stars GCNS
- Short Name:
- eDR3 GCNS SCS
- Date:
- 27 Dec 2024 08:31:02
- Publisher:
- The GAVO DC team
- Description:
- This is a clean and well characterised catalogue of objects within 100pc of the Sun from the Gaia early third data release. We characterise the catalogue using the full data release, and comparisons to other catalogues in literature and simulations. For all candidates (measured parallax < 8 mas), we calculate a distance probability function using Bayesian procedures and mock catalogues for the prediction of the priors. For each entry using a random forest classifier we attempt to remove sources with spurious astrometric solutions. This results in 331312 objects that should contain at least 92% of stars within 100 pc at spectral type M9. GCNS comes with several auxiliary tables, in particular lists of resolved stellar systems, of known neary stars not found in eDR3 and of candidates of Hyades and ComaBer cluster members.
- ID:
- ivo://astronet.ru/cas/galah_dr2
- Title:
- The GALAH survey: Second data release (Buder+, 2018)
- Short Name:
- galah_dr2
- Date:
- 17 Jun 2006 18:44:05
- Publisher:
- Sternberg Astronomical Institute Virtual Observatory Project
- Description:
- </pre><p>GALAH is a large-scale stellar spectroscopic survey project exploring the history of star formation, chemical evolution, stellar migration and minor mergers in the Milky Way. One of the main science goals of GALAH is to use chemical tagging to identify groups of stars that formed at the same place and time, even though they have dispersed throughout the Galaxy, using the similarity of their chemical abundance patterns. Using the HERMES spectrograph at the Anglo-Australian Telescope, we collect high-resolution (R~28,000) spectra for 360 stars simultaneously. These stars are selected simply in magnitude (14>V>12), Galactic latitude (|b|>10) and declination (dec<+10) to maximise our ability to learn about the underlying structure of the Galaxy. <p>There are 342,682 unique stars in DR2, observed between January 2014 and January 2018. For these stars, we have derived radial velocities, stellar parameters, and the abundances of up to 23 elements per star.
- ID:
- ivo://CDS.VizieR/VIII/105
- Title:
- The GLEAM 4-Jy (G4Jy) Sample
- Short Name:
- VIII/105
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Murchison Widefield Array (MWA) has observed the entire southern sky (Declination, {delta}<30{deg}) at low radio-frequencies, over the range 72-231MHz. These observations constitute the GaLactic and Extragalactic All-sky MWA (GLEAM) Survey, and we use the extragalactic catalogue (Galactic latitude, |b|>10{deg}) to define the GLEAM 4-Jy (G4Jy) Sample. This is a complete sample of the 'brightest' radio-sources (S_151MHz_>4Jy), the majority of which are active galactic nuclei with powerful radio-jets. Crucially, low-frequency observations allow the selection of such sources in an orientation-independent way (i.e. minimising the bias caused by Doppler boosting, inherent in high-frequency surveys). We then use higher-resolution radio images, and information at other wavelengths, to morphologically classify the brightest components in GLEAM. We also conduct cross-checks against the literature, and perform internal matching, in order to improve sample completeness (which is estimated to be >95.5%). This results in a catalogue of 1,863 sources, making the G4Jy Sample over 10 times larger than that of the revised Third Cambridge Catalogue of Radio Sources (3CRR; S_178MHz_>10.9Jy). Of these G4Jy sources, 78 are resolved by the MWA (Phase-I) synthesised beam (~2' at 200MHz), and we label 67% of the sample as 'single', 26% as 'double', 4% as 'triple', and 3% as having 'complex' morphology at ~1GHz (45" resolution). We characterise the spectral behaviour of these objects in the radio, and find that the median spectral-index is {alpha}=-0.740+/-0.012 between 151MHz and 843MHz, and {alpha}=-0.786+/-0.006 between 151MHz and 1400MHz (assuming a power-law description, S_{nu}_{prop.to}{nu}^{alpha}^), compared to {alpha}=-0.829+/-0.006 within the GLEAM band. Alongside this, our value-added catalogue provides mid-infrared source associations (subject to 6" resolution at 3.4um) for the radio emission, as identified through visual inspection and thorough checks against the literature. As such, the G4Jy Sample can be used as a reliable training set for cross-identification via machine-learning algorithms. We also estimate the angular size of the sources, based on their associated components at ~1GHz, and perform a flux-density comparison for 67 G4Jy sources that overlap with 3CRR. Analysis of multi-wavelength data, and spectral curvature between 72MHz and 20GHz, will be presented in subsequent papers, and details for accessing all G4Jy overlays are provided at https://github.com/svw26/G4Jy.
865. The GPM catalog
- ID:
- ivo://CDS.VizieR/I/285
- Title:
- The GPM catalog
- Short Name:
- I/285
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- GPM is the newer version of the General Compiled Catalogue of Absolute Proper Motions, derived with respect to galaxies within the plan called Catalogue of Faint Stars (KSZ, Deutch, 1952, Trans. IAU, Vol. 8, 789). The programme was proposed for several observatories of the former Soviet Union, China, Rumania and Spain. There are some resulting individual catalogues of absolute proper motions of stars compiled at five observatories (Kiev, Pulkovo, Moscow, Tashkent and Shanghai). The GPM combines these catalogues and comprises absolute proper motions for 52805 stars from 8 to 15.5mag in 185 fields north of -25 degrees of declination. The size of each region is nearly 1.5 square degrees. The mean standard error of proper motion is 8 mas/yr on average. Detailed information on the construction methodology and input data can be found in (Rybka & Yatsenko, 1997KFNT...13e..70R). In addition to absolute proper motions the GPM contains accurate equatorial coordinates and three-colour B V R photometry for the vast majority of its stars (Rybka 2000KFNT...16e..60R). Additional information was selected from all available sources. Usage of the ACT catalog should provide improved positions (mostly in removing of systematic errors) and improved photometry (because the brightest stars in each GPM region had B and V magnitudes measured by the Tycho experiment on the Hipparcos satellite). The mean accuracies achived, as demonstrated by comparison with above catalogue, are 250 mas for the positions and 0.22mag for B magnitude and 0.26mag for B-V colour. The GPM gives right ascensions and declinations for equinox J2000.0 and epoch copied from available sources. They were only presented to identify the GPM stars with those from other catalogues. The compiled catalogue also presents B magnitudes and B-V colours. They were converted to be close to Johnson system. The Tycho stars were also identified in the GPM catalogue. A search area with a radius of 2 arcseconds was used to search for multiple entries of the same star, which may be appeared in the region overlap areas. The detected entries were then removed from the final catalogue. The procedure decreased the number of stars in the catalogue by about 0.4 %. The adopted catalogue organization includes data in 185 regions sorted according the KSZ region numbers. The data were then sorted nearly in right ascension order within each GPM region. All information needed to associate a point on the sky with region number and provide a more rapid access to that region are given in file region.dat.
- ID:
- ivo://astronet.ru/cas/gsc2_3_2
- Title:
- The Guide Star Catalog II (GSC-II), version 2.3.2
- Short Name:
- gsc2_3_2
- Date:
- 17 Jun 2006 18:44:05
- Publisher:
- Sternberg Astronomical Institute Virtual Observatory Project
- Description:
- The Guide Star Catalog II (GSC-II) is an all-sky optical catalog based on 1" resolution scans of the photographic Sky Survey plates, at two epochs and three bandpasses, from the Palomar and UK Schmidt telescopes. This all-sky catalog will ultimately contains positions, proper motions, classifications, and magnitudes in multiple bandpasses for almost a billion objects down to approximately Jpg=21, Fpg=20. The GSC-II is currently used for HST Bright Object Protection, and will replace GSC-I for HST pointing in cycle 15. Looking ahead, the GSC-II will form the basis of the Guide Star Catalog for JWST. This was constructed in collaboration with ground-based observatories
- ID:
- ivo://astronet.ru/cas/gsc1_2
- Title:
- The Guide Star Catalog Version 1.2
- Short Name:
- gsc1_2
- Date:
- 17 Jun 2006 18:44:05
- Publisher:
- Sternberg Astronomical Institute Virtual Observatory Project
- Description:
- The Guide Star Catalog (GSC), which has been constructed to support the operational need of the Hubble Space Telescope contains nearly 19 million objects brighter than sixteenth magnitude, of which more than 15 million are classified as stars. This catalog provides positions and magnitudes for these stars. The original version of this catalog, GSC 1.0, is described in a series of papers: Lasker et al. (1990AJ.....99.2019L); Russell et al. (1990AJ.....99.2059R); and Jenkner et al. (1990AJ.....99.2082J) The reference material for the GSC 1.2 reduction is the "Positions and Proper Motions Catalogue": PPM-North, Roeser S. and Bastian U., 1988 PPM-South, Bastian U. and Roeser S., 1993 PPM-Suppl, Roeser S., Bastian U. and Kuzmin A., 1994 and the Astrographic Catalogue (AC) which was used to remove the mean systematics common to all the plates. The overall rms error of the GSC 1.2 is estimated better than 0.3arcsec
- ID:
- ivo://CDS.VizieR/J/A+A/570/A11
- Title:
- The Hawk-I UDS and GOODS Survey (HUGS)
- Short Name:
- J/A+A/570/A11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a new, ultra-deep, near-infrared imaging survey executed with the Hawk-I imager at the ESO VLT, of which we make all the data (images and catalog) public. This survey, named HUGS (Hawk-I UDS and GOODS Survey), provides deep, high-quality imaging in the K and Y bands over the portions of the UKIDSS UDS and GOODS-South fields covered by the CANDELS HST WFC3/IR survey. In this paper we describe the survey strategy, the observational campaign, the data reduction process, and the data quality. We show that, thanks to exquisite image quality and extremely long exposure times, HUGS delivers the deepest K-band images ever collected over areas of cosmological interest, and in general ideally complements the CANDELS data set in terms of image quality and depth. In the GOODS-S field, the K-band observations cover the whole CANDELS area with a complex geometry made of 6 different, partly overlapping pointings, in order to best match the deep and wide areas of CANDELS imaging. In the deepest region (which includes most of the Hubble Ultra Deep Field) exposure times exceed 80 hours of integration, yielding a 1-{sigma} magnitude limit per square arcsec of ~=28.0ABmag. The seeing is exceptional and homogeneous across the various pointings, confined to the range 0.38-0.43arcsec. In the UDS field the survey is about one magnitude shallower (to match the correspondingly shallower depth of the CANDELS images) but includes also Y-band band imaging (which, in the UDS, was not provided by the CANDELS WFC3/IR imaging). In the K-band, with an average exposure time of 13 hours, and seeing in the range 0.37-0.43arcsec, the 1-{sigma} limit per square arcsec in the UDS imaging is ~=27.3ABmag. In the Y-band, with an average exposure time ~=8h, and seeing in the range 0.45-0.5arcsec, the imaging yields a 1-{sigma} limit per square arcsec of ~=28.3ABmag. We show that the HUGS observations are well matched to the depth of the CANDELS WFC3/IR data, since the majority of even the faintest galaxies detected in the CANDELS H-band images are also detected in HUGS. Finally we present the K-band galaxy number counts produced by combining the HUGS data from the two fields. We show that the slope of the number counts depends sensitively on the assumed distribution of galaxy sizes, with potential impact on the estimated extra-galactic background light.
- ID:
- ivo://CDS.VizieR/J/MNRAS/419/3505
- Title:
- The HeViCS Bright Galaxy Sample
- Short Name:
- J/MNRAS/419/3505
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe the Herschel Virgo Cluster Survey and the first data that cover the complete survey area (four 4x4deg^2^ regions). We use these data to measure and compare the global far-infrared properties of 78 optically bright galaxies that are selected at 500um and detected in all five far-infrared bands. We show that our measurements and calibration are broadly consistent with previous data obtained by the IRAS, ISO, Spitzer and Planck. We use SPIRE and PACS photometry data to produce 100-, 160-, 250-, 350- and 500-um cluster luminosity distributions.
- ID:
- ivo://CDS.VizieR/I/239
- Title:
- The Hipparcos and Tycho Catalogues
- Short Name:
- I/239
- Date:
- 18 Nov 2021 11:08:10
- Publisher:
- CDS
- Description:
- The Hipparcos and Tycho Catalogues are the primary products of the European Space Agency's astrometric mission, Hipparcos. The satellite, which operated for four years, returned high quality scientific data from November 1989 to March 1993. Each of the catalogues contains a large quantity of very high quality astrometric and photometric data. In addition there are associated annexes featuring variability and double/multiple star data, and solar system astrometric and photometric measurements. In the case of the Hipparcos Catalogue, the principal parts are provided in both printed and machine-readable form (on CDROM). In the case of the Tycho Catalogue, results are provided in machine-readable form only (on CDROM). Although in general only the final reduced and calibrated astrometric and photometric data are provided, some auxiliary files containing results from intermediate stages of the data processing, of relevance for the more-specialised user, have also been retained for publication. (Some, but not all, data files are available from the Centre de Donnees astronomiques de Strasbourg.) The global data analysis tasks, proceeding from nearly 1000 Gbit of raw satellite data to the final catalogues, was a lengthy and complex process, and was undertaken by the NDAC and FAST Consortia, together responsible for the production of the Hipparcos Catalogue, and the Tycho Consortium, responsible for the production of the Tycho Catalogue. A fourth scientific consortium, the INCA Consortium, was responsible for the construction of the Hipparcos observing programme, compiling the best-available data for the selected stars before launch into the Hipparcos Input Catalogue. The production of the Hipparcos and Tycho Catalogues marks the formal end of the involvement in the mission by the European Space Agency and the four scientific consortia. For more complete and detailed information on the data, the user is advised to refer to Volume 1 ("Introduction and Guide to the Data", ESA SP-1200) of the printed Hipparcos and Tycho Catalogues. The user should also note that in order to convert the Double and Multiple Systems (Component solutions) data file hip_dm_c.dat into FITS format it is first necessary to filter the file according to whether the entry is a component record (identified by COMP in field DCM5) or a correlation record (identified by CORR in field DCM5) because of the different structures of the respective records. On a Unix system this can be achieved as follows: grep COMP hip_dm_c.dat > h_dm_com.dat grep CORR hip_dm_c.dat > h_dm_cor.dat The catalogue description file (this file) gives the relevant information for converting the main data files, including h_dm_cor.dat and h_dm_com.dat, into FITS format. The machine readable data files (i.e. those available on CD-ROM and the subset available from the CDS) contain several extra fields in addition to the data from the printed catalogue. These fields are identified by the letter `M' in the data label (e.g. the field DGM1 contains data only available in the machine readable file hip_dm_g.dat).