- ID:
- ivo://CDS.VizieR/J/A+AS/120/201
- Title:
- Extragalactic radio sources optical positions
- Short Name:
- J/A+AS/120/201
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on 28 individual catalogues, in which the positions of optical counterparts of extragalactic radio sources are listed, we compiled a combined catalogue by means of a weighted least squares adjustment. The catalogue is in the system of FK5/J2000.0. It consists of about five hundred sources, among which there are 56 primary sources with position uncertainties as 0.09". Comparisons show that the orientation differences between optical and radio frames are A1=-0.013"+/-0.012", A2=0.077"+/-0.012", A3=0.005"+/-0.009". Local relative deformations are not obvious within the precision of ground-based optical observations.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/I/273A
- Title:
- Extragalactic Reference Link Catalog (ERLcat)
- Short Name:
- I/273A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is an astrometric catalog, providing positions of 89,422 stars in 398 selected fields of extragalactic reference frame sources. The stars are mainly in the 11 to 14 magnitude range. The average positional accuracy is about 50 mas per coordinate at the epoch of observation, which is between 1976.2 and 1991.9. The observations are based on photographic plates, taken with 2 telescopes which are: - the Hamburg Zone astrograph (in the Northern Hemisphere) - the USNO Twin astrograph at Black Birch (New Zealand)
- ID:
- ivo://CDS.VizieR/J/ApJS/89/259
- Title:
- Far-UV photometry in Ori
- Short Name:
- J/ApJS/89/259
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/A+A/426/367
- Title:
- FBS blue stellar objects DSS1/DSS2 astrometry
- Short Name:
- J/A+A/426/367
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accurate measurements of the positions of 1103 First Byurakan Survey (FBS) blue stellar objects (the Second part of the FBS, <II/223>) have been carried out on the DSS1 and DSS2 (red and blue images). To establish the accuracy of the DSS1 and DSS2, measurements have been made for 153 AGN for which absolute VLBI coordinates have been published. The rms errors are: 0.45" for DSS1, 0.33" for DSS2 red, and 0.59" for DSS2 blue in each coordinate, the corresponding total positional errors being 0.64", 0.46", and 0.83", respectively. The highest accuracy (0.42") is obtained by weighted averaging of the DSS1 and DSS2 red positions. It is shown that by using all three DSS images accidental errors can be significantly reduced. The comparison of DSS2 and DSS1 images made it possible to reveal positional differences and proper motions for 78 objects (for 62 of these for the first time), including new high-probability candidate white dwarfs, and to find objects showing strong variability, i.e. high-probability candidate cataclysmic variables.
- ID:
- ivo://CDS.VizieR/J/A+A/431/143
- Title:
- Field horizontal-branch stars in the Galaxy
- Short Name:
- J/A+A/431/143
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a sample of 8321 candidate Field Horizontal-Branch (FHB) stars selected by automatic spectral classification in the digital data base of the Hamburg/ESO objective-prism survey. The stars are distributed over 8225 square degrees of the southern sky, at |b|>~30{deg}. The average distance of the sample, assuming that they are all FHB stars, is 9.8kpc, and distances of up to ~30kpc are reached. Moderate-resolution spectroscopic follow-up observations and $UBV$ photometry of 125 test sample stars demonstrate that the contamination of the full candidate sample with main-sequence A-type stars is <16%, while it would be up to 50% in a flux-limited sample at high galactic latitudes. Hence more than ~6800 of our FHB candidates are expected to be genuine FHB stars. The candidates are being used as distance probes for high-velocity clouds and for studies of the structure and kinematics of the Galactic halo.
- ID:
- ivo://CDS.VizieR/I/175
- Title:
- Fifth Fundamental Catalogue (FK5) - Extension
- Short Name:
- I/175
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The FK5 Extension provides improved mean positions and proper motions for the 3117 new fundamental stars. The machine version of the catalog contains the positions and proper motions of the Extension stars for the epochs and equinoxes J2000.0 and B1950.0, the mean epochs of individual observed right ascensions and declinations used to determine the final positions, the mean errors of the final positions and proper motions for the reported epochs, and ancillary data such as magnitudes, spectral types, parallaxes, and radial velocities. Cross identifications to the numbering systems of the AGK3R, SRS, HD, DM, and GC catalogs are also included.
- ID:
- ivo://CDS.VizieR/I/149A
- Title:
- Fifth Fundamental Catalogue (FK5) Part I
- Short Name:
- I/149A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Basic Fifth Fundamental Catalogue (FK5) Part I provides improved mean positions and proper motions for the 1535 classical fundamental stars that had been included in the FK3 and FK4 catalogs. The machine version of the catalog contains the positions and proper motions of the Basic FK5 stars for the epochs and equinoxes J2000.0 and B1950.0, the mean epochs of individual observed right ascensions and declinations used to determine the final positions, the mean errors of the final positions and proper motions for the reported epochs, and ancillary data such as magnitudes, spectral types, parallaxes, radial velocities, and cross identifications to other catalog designations.
- ID:
- ivo://CDS.VizieR/J/AJ/133/1236
- Title:
- Fifth VLBA calibrator survey: VCS5
- Short Name:
- J/AJ/133/1236
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents the fifth part of the Very Long Baseline Array (VLBA) Calibrator Survey (VCS), containing 569 sources not observed previously with very long baseline interferometry in geodetic or absolute astrometry programs. This campaign has two goals: (1) to observe additional sources that, together with previous survey results, form a complete sample, and (2) to find new strong sources suitable as phase calibrators. This VCS extension was based on three 24-hr VLBA observing sessions in 2005. It detected almost all extragalactic flat-spectrum sources with correlated flux density greater than 200mJy at 8.6GHz above declination -30{deg} that were not observed previously. Source positions with milliarcsecond accuracy were derived from astrometric analysis of ionosphere-free combinations of group delays determined from the 2.3 and 8.6GHz frequency bands. The VCS5 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 on the World Wide Web at http://vlbi.gsfc.nasa.gov/vcs5
- 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.
- 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.
