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291. Large Quasar Astrometric Catalogue 2 (LQAC-2)
ID:
ivo://CDS.VizieR/J/A+A/537/A99
Title:
Large Quasar Astrometric Catalogue 2 (LQAC-2)
Short Name:
J/A+A/537/A99
Date:
21 Oct 2021
Publisher:
CDS
Description:
First of all we make a substantial review of the definitions and properties of quasars and AGN (Active Galactic Nuclei), the differenciation of these objects being unclear in the literature and even for specialists. This will serve our purpose when deciding which kinds of objects will be taken into account in our compilation. Then we carry out the cross-identification between the 9 catalogues of quasars chosen for their accuracy and their huge number of objects, using a flag for each of them, and including all the available data related to magnitudes (infrared and optical), radiofluxes and redshifts. We also perform cross identification with external catalogues 2MASS, B1.0 and GSC2.3 in order to complete photometric data of the objects. Moreover we compute the absolute magnitude of our extragalactic objects by taking into account the recent studies concerning the galactic absorption. In addition substantial improvements are brought with respect to the first release of the LQAC (Souchay et al., 2009, Cat. J/A+A/494/799). At first a LQAC name is given for each object based on its equatorial coordinates with respect to the ICRS, following a procedure which creates no ambiguity for identification. At second the equatorial coordinates of the objects are recomputed more accurately according to the algorithms used for the elaboration of the Large Quasar Reference Frame (LQRF) (Andrei et al., 2009, Cat. I/313). At third we introduce a morphological classification for the objects which enables in particular to define clearly if the object is point-like or extended. Our final catalogue, called LQAC-2, contains 187 504 quasars. This is roughly larger than the 113 666 quasars recorded in the first version of the LQAC (Souchay et al., 2009, Cat. J/A+A/494/799) and a little more than the number of quasars recorded in the up-dated version of the Veron Cetty and Veron (2010, Cat. VII/258) catalogue, which was the densest compilation of quasars up to now. In addition to the quantitative and qualitative improvements brought by our compilation, we discuss the homogeneity of the data and carry out statistical analysis concerning the spatial density and the distance to the closest neighbour.
292. Large Quasar Astrometric Catalogue 4, LQAC-4
ID:
ivo://CDS.VizieR/J/A+A/614/A140
Title:
Large Quasar Astrometric Catalogue 4, LQAC-4
Short Name:
J/A+A/614/A140
Date:
21 Oct 2021
Publisher:
CDS
Description:
From an astrometric point of view, quasars constitute the best and almost ideal reference objects in the celestial sphere, with a priori no significant proper motion. Since the third release of the Large Quasar Astrometric Catalogue (LQAC-3, Cat. J/A+A/583/A75), a large number of quasars have been discovered, in particular those coming from the DR12Q release of the SDSS (Paris et al., 2017, Cat. VII/279). Moreover, for cross-matched objects, we have taken advantage of the very accurate determinations of the quasars identified within the recent Gaia DR1 catalogue (2018, Cat. I/345). Following the same procedure as in the three previous releases of the LQAC, our aim is to compile the large majority of all the quasars recorded so far. Our goal is to record their best coordinates and substantial information concerning their physical properties such as the redshift as well as multi-bands apparent and absolute magnitudes. Emphasis is given to the results of the cross-matches with the Gaia DR1 catalogue. New quasars coming from the DR12Q release were cross-matched with the precedent LQAC-3 compilation with a 1" search radius, in order to add the objects without counterpart to the LQAC-4 compilation. A similar cross-match was done with Gaia DR1 to identify the known quasars detected by Gaia. This enables one to improve significantly the positioning of these objects, and in parallel to study the astrometric performance of the individual catalogues of the LQAC-4 compilation. Finally, a new method was used to determine absolute magnitudes. Our final catalogue, called LQAC-4, contains 443 725 objects. This is roughly 37.82% more than the number of objects recorded in the LQAC-3. Among them, 249071 were found in common with the Gaia DR1, with a 1" search radius. That corresponds to 56.13% of the whole population in the compilation. The LQAC-4 delivers to the astronomical community a nearly complete catalogue of spectroscopically confirmed quasars (including a small proportion of compact AGNs), with the aim of giving their best equatorial coordinates with respect to the ICRF2 and with exhaustive additional information. For more than 50% of the sample, these coordinates come from the very recent Gaia DR1.
293. Large Quasar Astrometric Catalogue 3 (LQAC-3)
ID:
ivo://CDS.VizieR/J/A+A/583/A75
Title:
Large Quasar Astrometric Catalogue 3 (LQAC-3)
Short Name:
J/A+A/583/A75
Date:
21 Oct 2021
Publisher:
CDS
Description:
From an astrometric point of view, quasars constitute quasi-ideal reference objects in the celestial sphere, with an a priori absence of proper motion. Since the second release of the Large Quasar Astrometric Catalog (LQAC), a large number of quasars have been discovered, in particular with the upcoming new release of the SDSS quasars catalog. Following the same procedure as in the two previous releases of the LQAC, our aim was to compile all the quasars recorded until the present date, with accurate recomputation of their equatorial coordinates in the ICRS and with the maximum of information concerning their physical properties, such as the redshift, the photometry, and the absolute magnitudes.
294. Large Quasar Astrometric Catalogue (LQAC)
ID:
ivo://CDS.VizieR/J/A+A/494/799
Title:
Large Quasar Astrometric Catalogue (LQAC)
Short Name:
J/A+A/494/799
Date:
21 Oct 2021
Publisher:
CDS
Description:
The very large and increasing number of quasars reckoned from various sky surveys leads to a large quantity of data which brings various and inhomogeneous information in the fields of astrometry, photometry, radioastronomy and spectroscopy. In this paper, we describe our work that aims to make available a general compilation of the largest number of recorded quasars obtained from all the available catalogues, with their best position estimates, and providing physical information at both optical and radio wavelengths.
295. Late-Type Extension to MoVeRS (LaTE-MoVeRS)
ID:
ivo://CDS.VizieR/J/AJ/153/92
Title:
Late-Type Extension to MoVeRS (LaTE-MoVeRS)
Short Name:
J/AJ/153/92
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the Late-Type Extension to the Motion Verified Red Stars (LaTE-MoVeRS) catalog, containing 46,463 photometric late-type (>M5) dwarfs within the Sloan Digital Sky Survey (SDSS) footprint. Proper motions were computed for objects combining astrometry from the SDSS Data Release 12 (DR12), the Two-micron All-Sky Survey (2MASS) Point Source Catalog, and the Wide-field Infrared Survey Explorer (WISE) AllWISE data sets. LaTE-MoVeRS objects were required to have significant proper motion . Using the LaTE-MoVeRS sample and Gaia Data Release 1, we estimate Gaia will be ~64% complete for very low-mass objects (>M5) in comparison to the combined SDSS+2MASS+WISE data set (i<21.3). We computed photometric distances and estimated stellar effective temperatures for the LaTE-MoVeRS catalog. The majority of the dwarfs in the sample have distances <150pc and T<3000K. Thirteen objects that have not been previously identified as nearby eff objects were identified within LaTE-MoVeRS with estimated photometric distances within 25pc. We also identified one new object that has not been previously identified with a large amount of excess mid-infrared flux (2MASS J11151597+1937266). This object appears to be an L2{gamma} at ~50pc showing spectroscopic signs of a flaring event (e.g., strong hydrogen Balmer emission lines). This object does not exhibit kinematics similar to any known kinematic association. The LaTE-MoVeRS catalog is available through SDSS CasJobs and VizieR.
296. LBA Calibrator Survey (LCS1)
ID:
ivo://CDS.VizieR/J/MNRAS/414/2528
Title:
LBA Calibrator Survey (LCS1)
Short Name:
J/MNRAS/414/2528
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalogue of accurate positions and correlated flux densities for 410 flat-spectrum, compact extragalactic radio sources previously detected in the AT20G survey. The catalogue spans the declination range [-90{deg}, -40{deg}] and was constructed from four 24-hour VLBI observing sessions with the Australian Long Baseline Array at 8.3GHz. The VLBI detection rate in these experiments is 97%, the median uncertainty of the source positions is 2.6mas, and the median correlated flux density on projected baselines longer than 1000km is 0.14Jy. The goals of this work are 1) to provide a pool of southern sources with positions accurate to a few milliarcsec, which can be used for phase referencing observations, geodetic VLBI and space navigation; 2) to extend the complete flux-limited sample of compact extragalactic sources to the southern hemisphere; and 3) to investigate the parsec-scale properties of high-frequency selected sources from the AT20G survey. As a result of this VLBI campaign, the number of compact radio sources south of declination -40 deg which have measured VLBI correlated flux densities and positions known to milliarcsec accuracy has increased by a factor of 3.5. The catalogue and supporting material is available at http://astrogeo.org/lcs1.
297. LFT Catalogue
ID:
ivo://CDS.VizieR/I/54A
Title:
LFT Catalogue
Short Name:
I/54A
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalogue, published in 1955, provides data about stars known to have proper motions exceeding 0.5" annually. Note that a more recent version, known as the "LHS" catalogue and containing 4471 stars, was published later in 1987 (catalogue I/87)
298. Lick Jupiter-Voyager Reference Star Catalogue
ID:
ivo://CDS.VizieR/I/152
Title:
Lick Jupiter-Voyager Reference Star Catalogue
Short Name:
I/152
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalog was prepared for purposes of determining up-to-date, reasonably accurate equatorial coordinates for reference stars in a band of sky against which cameras of the Voyager spacecraft were aligned for observations of Jovian satellites during the Jupiter flyby. The catalog contains accurate equatorial coordinates for equinox 1950.0, epoch 1978.27, photographic and visual magnitudes, AGK3 identifications and proper motions for 4983 stars. All of the reference stars are in the range 6h00m to 8h04m in right ascension (1950), declination zones +16 to +23 degrees, and 8h31m to 8h57m, zones +08 to +14 degrees. Mean errors of the positions are about 0.4 second of arc.
299. Lick Northern Proper Motion: NPM1 Ref. Galaxies
ID:
ivo://CDS.VizieR/I/200
Title:
Lick Northern Proper Motion: NPM1 Ref. Galaxies
Short Name:
I/200
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Lick Northern Proper Motion (NPM) program measured proper motions, positions, and photographic photometry for some 149,000 stars (NPM1 Catalog) covering the sky outside the Milky Way north of declination 23 degrees. The NPM1 proper motions were measured with respect to an absolute reference frame defined by some 50,000 faint galaxies (mostly 16 < B < 18 mag). The rms position errors for the NPM1 reference galaxies average 0.2 arcsec. The rms errors for the B magnitudes average 0.25 mag. More complete descriptive information is available in the ASCII or LaTeX documentation written by R.B. Hanson (UCO/Lick Obs.).
300. Lick Northern Proper Motion Program: NPM1 Catalog
ID:
ivo://CDS.VizieR/I/199A
Title:
Lick Northern Proper Motion Program: NPM1 Catalog
Short Name:
I/199A
Date:
21 Oct 2021
Publisher:
CDS
Description:
The NPM1 catalog is the first part of the Lick Northern Proper Motion (NPM) program to measure absolute proper motions, on an inertial system defined by some 50,000 faint galaxies, for some 300,000 stars over a blue apparent magnitude range from 8 to 18. There are 1246 6-degree by 6-degree fields in the NPM survey (to declination -23 degrees). The NPM1 catalog covers the 72% of the northern sky lying outside the Milky Way and contains some 149,000 stars from measures in 899 of the 1246 NPM fields. A second catalog (NPM2) will cover the NPM Milky Way fields. The Yale Southern Proper Motion (SPM) program will complete the southern sky. Each NPM field was photographed at two epochs between 1947 and 1988. The mean first and second epochs are 1950 and 1977; the average epoch difference is 27 years. The first-epoch plates were taken in the blue only; both blue and yellow plates were taken at the second epoch. Some 94000 stars were chosen anonymously for the NPM astrometric reductions and for statistical studies of stellar motions. In addition, the NPM1 catalog contains some 28000 positional reference stars, and some 27000 stars were chosen from the Lick Input Catalog of Special Stars (ICSS). The previous version of the NPM1 Catalog (I/199) deposited with the data centers (ADC and CDS) gives positions for equinox B1950 and computed epoch 1950, and is in one data file (148,940 lines) concatenating the 114 one-degree declination zones from +90 degrees to -23 degrees. Each star has an NPM1 "name" reflecting the declination zone and a running number in right ascension order within the zone. The present J2000 version gives the NPM1 positions transformed into the J2000 system and updated to the epoch 2000 using the NPM1 proper motions. The proper motions have been rotated into the J2000 coordinate system. The J2000 NPM1 Catalog is ordered in zones from +90 degrees to -23 degrees, and within each zone, the stars are sorted in right ascension order. To avoid "renaming" stars, the B1950 NPM1 "names" were retained, but the user must note that these no longer strictly reflect the declination zone and right ascension order in the J2000 NPM1 Catalog. The J2000 NPM1 Catalog is also available as 114 separate files, one for each declination zone from +90 degrees (z+90j) to -23 degrees (z-23j), from http://www.ucolick.org/~npm/NPM1/zones/ Each star's entry includes the absolute proper motion and blue magnitude. For 97% of the stars the color is also given. Other data given for each star are: the original mean epoch, a stellar class code, the number of NPM fields measured, and discrepancy flags for position, proper motion, and photometry. Finally, as an additional identification, the AGK3 (north) or SAO (south) number (if any) is given. The rms errors of the NPM absolute proper motions are about 0.5"/cent in each coordinate. The rms position errors at the catalog epoch 1950 average about 0.15" in each coordinate. The rms errors for the NPM photographic photometry average about 0.2 mag in B, and 0.15 mag in B-V. More complete information is available in the PostScript documentation for the 1993 (B1950) NPM1 Catalog (npm1b.ps), written by R.B. Hanson. We thank the National Science Foundation for its continued support of the NPM program. Recent work was supported by NSF grant AST-9530632. Current work is supported by NSF grant AST-9988105.

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