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201. First brown dwarfs discovered by WISE
ID:
ivo://CDS.VizieR/J/ApJS/197/19
Title:
First brown dwarfs discovered by WISE
Short Name:
J/ApJS/197/19
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present ground-based spectroscopic verification of 6 Y dwarfs (see also Cushing et al., 2011ApJ...743...50C), 89 T dwarfs, 8 L dwarfs, and 1 M dwarf identified by the Wide-field Infrared Survey Explorer (WISE). Eighty of these are cold brown dwarfs with spectral types >=T6, six of which have been announced earlier by Mainzer et al. (2011ApJ...726...30M) and Burgasser et al. (2011ApJ...735..116B). We present color-color and color-type diagrams showing the locus of M, L, T, and Y dwarfs in WISE color space. Near-infrared and, in a few cases, optical spectra are presented for these discoveries. Near-infrared classifications as late as early Y are presented and objects with peculiar spectra are discussed. Using these new discoveries, we are also able to extend the optical T dwarf classification scheme from T8 to T9. After deriving an absolute WISE 4.6um (W2) magnitude versus spectral type relation, we estimate spectrophotometric distances to our discoveries. We also use available astrometric measurements to provide preliminary trigonometric parallaxes to four of our discoveries, which have types of L9 pec (red), T8, T9, and Y0; all of these lie within 10pc of the Sun. The Y0 dwarf, WISE 1541-2250, is the closest at 2.8^+1.3^_-0.6_pc; if this 2.8pc value persists after continued monitoring, WISE 1541-2250 will become the seventh closest stellar system to the Sun. Another 10 objects, with types between T6 and >Y0, have spectrophotometric distance estimates also placing them within 10pc. The closest of these, the T6 dwarf WISE 1506+7027, is believed to fall at a distance of ~4.9pc. WISE multi-epoch positions supplemented with positional info primarily from the Spitzer/Infrared Array Camera allow us to calculate proper motions and tangential velocities for roughly one-half of the new discoveries.
202. First, Second and Third Herstmonceux Cats, 1950.0
ID:
ivo://CDS.VizieR/I/144
Title:
First, Second and Third Herstmonceux Cats, 1950.0
Short Name:
I/144
Date:
21 Oct 2021
Publisher:
CDS
Description:
These catalogues contain the results of observations of stars made at the Royal Greenwich Observatory (Herstmonceux) with the Cooke Transit Circle from 1957 October 22 to 1980 November 18. The first Herstmonceux catalogue includes observations from 1957 October 22 to 1961 June 30, the second from 1961 October 17 to 1969 January 29, and third from 1969 February 13 to 1980 November 18.
203. Fitted proper motions for the DR solution
ID:
ivo://CDS.VizieR/J/A+A/559/A95
Title:
Fitted proper motions for the DR solution
Short Name:
J/A+A/559/A95
Date:
21 Oct 2021
Publisher:
CDS
Description:
We propose new estimates of the secular aberration drift, mainly due to the rotation of the Solar System about the Galactic center, based on up-to-date VLBI observations and and improved method of outlier elimination. We fit degree-2 vector spherical harmonics to extragalactic radio source proper motion field derived from geodetic VLBI observations spanning 1979-2013. We pay particular attention to the outlier elimination procedure to remove outliers from (i) radio source coordinate time series and (ii) the proper motion sample. We obtain more accurate values of the Solar system acceleration compared to those in our previous paper. The acceleration vector is oriented towards the Galactic center within ~7{deg}. The component perpendicular to the Galactic plane is statistically insignificant. We show that an insufficient cleaning of the data set can lead to strong variations in the dipole amplitude and orientation, and statistically biased results.
204. FK5 - SAO - HD - Common Name Cross Index
ID:
ivo://CDS.VizieR/IV/22
Title:
FK5 - SAO - HD - Common Name Cross Index
Short Name:
IV/22
Date:
21 Oct 2021
Publisher:
CDS
Description:
The author has combined data from various catalogs to produce a cross index of the numbers in the FK5 (I/149, I/175), SAO (I/131), and HD (III/135) catalogs. He has also added the Bayer or Flamsteed designations and the common or variable star names.
205. FOCAT-S Catalogue
ID:
ivo://CDS.VizieR/I/195
Title:
FOCAT-S Catalogue
Short Name:
I/195
Date:
21 Oct 2021
Publisher:
CDS
Description:
This is a new reduction of FOCAT-S photographic catalogue of southern stars. This reduction has to replace the preceding one. The differences from previous version are as follows: 1. The new version was sorted according right ascension of stars inside 10-degree declination zone; 2. New proper motions were calculated for all almost stars. New Astrographic Catalogue plate reduction was developed for this aim. The average rms of new FOCAT-S proper motions is 0.002 - 0.003 "/year; 3. The number of the Astrographic Catalogue star positions used for the proper motion calculation is added; 4. The magnitude (mag) and spectral type (Sp) columns were revised significantly: some errors were corrected; stars identified in C.S.I. catalogue have got Mag, Sp from this catalogue as it was in previous version. Other stars have got Mag, Sp from PPM-S catalogue. 5. The list of Durchmusterung star numbers was changed. Now it contains the Cape Photographic Durchmusterung (CPD) numbers for stars in [-90, -23] declination zones; Cordoba Durchmusterung (CoD) star numbers are used only if it was impossible to identify star in BD or CPD. Format of this column was changed also. 6. PPM catalogue star numbers were added.
206. FON Astrographic Catalogue Southern Part (FONAC-S)
ID:
ivo://CDS.VizieR/I/346
Title:
FON Astrographic Catalogue Southern Part (FONAC-S)
Short Name:
I/346
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalog of positions and B-magnitudes of stars and galaxies of the southern sky (from -20{deg} to +2{deg}) was created as a part of the FON (Russian abbreviation Photographic Sky Survey) project at the Ulugh Beg Astronomical Institute (UBAI) of the Uzbekistan Academy of Sciences. The data accumulated in the Photographic Archive of the UBAI were used. The total number of processed plates is 1963. Astronegatives were digitized with Epson Expression 10000XL scanners in the 1200 dpi scanning mode. The majority of plates have a size of 30x30cm. The catalog contains the data on 13 413 268 stars and galaxies with B<=17.5m at the epoch of 1984.97. The coordinates of stars and galaxies were obtained in the Tycho-2 reference system, and B-magnitudes were determined in the system of photoelectric standards. The mean internal errors of the catalog are {sigma}_RA,DE_=0.23" and {sigma}_B_=0.15mag for all objects or {sigma}_RA,DE_=0.085" and {sigma}_B_=0.054mag for the objects in the B=7-14mag range. The convergence between the catalog and Tycho-2 is characterized by the following values: 0.042" and 0.16m. The mean-square difference in coordinates from the catalog and from UCAC-4 is {sigma}_RA,DE_=0.26" (9 892 697 objects, or 73.75% of stars and galaxies, were identified).
207. FON Astrographic Catalogue, Version 3.0
ID:
ivo://CDS.VizieR/I/342
Title:
FON Astrographic Catalogue, Version 3.0
Short Name:
I/342
Date:
05 Nov 2021
Publisher:
CDS
Description:
The catalog of equatorial coordinates {alpha} and {delta} and B-magnitudes of stars of the northern sky (from -4{deg} to +90{deg}) was created as a part of the FON project at the Main Astronomical Observatory of the National Academy of Sciences of Ukraine. The data accumulated in the Joint Digital Archive of the Ukrainian Virtual Observatory were used. The total number of processed plates is 2260. Astronegatives were digitized with Microtek ScanMaker 9800XL TMA and Epson Expression 10000XL scanners in the 1200 dpi scanning mode. The majority of plates have a size of 30x30cm (13000x13000-pixels). The catalog contains the data on 19451751 stars and galaxies with B<=16.5m at the epoch of 1988.1. The coordinates of stars and galaxies were obtained in the Tycho-2 reference system, and B-magnitudes were determined in the system of photoelectric standards. The mean internal errors of the catalog are {simag}_RA,DE_=0.23" and {sigma}_B_=0.14mag for all objects or {simag}_RA,DE_=0.10" and {sigma}_B_=0.07mag for stars in the B=7-14mag range. The convergence between the catalog and Tycho-2 is characterized by the following values: 0.06" and 0.15m. The mean-square difference in coordinates from the catalog and from UCAC-4 is {simag}_RA,DE_= 0.30" (18 742 932 objects, or 96.36% of stars and galaxies, were cross-identified).
208. Fourth Fundamental Cat and Suppl (FK4, FK4S)
ID:
ivo://CDS.VizieR/I/143
Title:
Fourth Fundamental Cat and Suppl (FK4, FK4S)
Short Name:
I/143
Date:
21 Oct 2021
Publisher:
CDS
Description:
The FK4 was an attempt to establish a fundamental system of stellar positions and proper motions for the 1950 equinox using as much position data as were available. Most of the stars are brighter than 7.0 mag. To increase the star density in some regions of the sky, positions and proper motions for additional stars were established on the same system. This catalog contains seven data files, six for different equinoxes (1950, 1955, 1960, 1965, 1970, and 1975) and one for the supplemental stars. The 1950 and 1975 files contain the complete FK4 catalog (1535 stars); the others contain only 52 polar stars. In addition to a header record, the primary catalog contains for each star an identification number; the magnitude (maximum for a variable star); a variability flag, the minimum magnitude for a variable or the magnitude of the secondary for a double star; the HD spectral type and the type for the companion or a second type for a variable star; the position and the change and acceleration of the position; the proper motion and its change with time; the mean epoch of the observations for both right ascension and declination; the standard deviations of the position and proper motion; the numbers of the star in the Boss General Catalog, the N30 catalog, and in the Durchmusterungs; and the parallax. The supplement has a flag to indicate duplicity but no information about variability or the second component. It has no information about the temporal change of the position and proper motion and does not list the N30 and Durchmusterung numbers. It also omits the mean epoch for the observations.
209. Fourth VLBA calibrator survey: VCS4
ID:
ivo://CDS.VizieR/J/AJ/131/1872
Title:
Fourth VLBA calibrator survey: VCS4
Short Name:
J/AJ/131/1872
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents the fourth extension to the VLBA Calibrator Survey, containing 258 new sources not previously observed with very long baseline interferometry (VLBI). This survey, based on three 24hr Very Long Baseline Array observing sessions, fills remaining areas on the sky above declination -40{deg} where the calibrator density is less than one source within a 4{deg} radius disk in any given direction. The share of these areas was reduced from 4.6% to 1.9%. Source positions were derived from astrometric analysis of group delays determined at 2.3 and 8.6GHz frequency bands using the Calc/Solve software package. The VCS4 catalog of source positions, plots of correlated flux density versus projected baseline length, contour plots, and fits files of naturally weighted CLEAN images, as well as calibrated visibility function files, are available online at http://vlbi.gsfc.nasa.gov/vcs4 .
210. Gaia catalog release 2
ID:
ivo://vopdc.obspm/gepi/gaia
Title:
Gaia catalog release 2
Short Name:
Gaia
Date:
14 Nov 2018 00:30:00
Publisher:
Paris Astronomical Data Centre - GEPI
Description:
The second Gaia data release, Gaia DR2, encompasses astrometry, photometry, radial velocities, astrophysical parameters (stellar effective temperature, extinction, reddening, radius, and luminosity), and variability information for up to 1.6 billion stars. Gaia DR2 is based on the first 22 months of the nominal, five-year mission, processed by the Gaia Data Processing and Analysis Consortium (DPAC).

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