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141. CCD photometry of omega Cen
ID:
ivo://CDS.VizieR/J/MNRAS/250/314
Title:
CCD photometry of omega Cen
Short Name:
J/MNRAS/250/314
Date:
21 Oct 2021
Publisher:
CDS
Description:
(no description available)
142. CCD positions for eight Jovian irregular satellites
ID:
ivo://CDS.VizieR/J/A+A/453/349
Title:
CCD positions for eight Jovian irregular satellites
Short Name:
J/A+A/453/349
Date:
21 Oct 2021
Publisher:
CDS
Description:
The astrometric positions of eight irregular Jovian satellites are given for the oppositions of the planet from 1995 to 1999. These positions were measured on 204 CCD frames obtained at the Cassegrain focus of a 1.6m reflector. They are compared with the theoretically calculated positions from JPL Development Ephemeris. The observed minus-calculated standard deviation for all observations of the eight satellites are {sigma}_RA_=0.071" and {sigma}_DE_=0.052". The USNO-A2.0 (<I/252>) catalog was used for the astrometric calibration.
143. 1995-1997 CCD positions of Triton
ID:
ivo://CDS.VizieR/J/A+AS/131/291
Title:
1995-1997 CCD positions of Triton
Short Name:
J/A+AS/131/291
Date:
21 Oct 2021
Publisher:
CDS
Description:
Astrometric observations of Triton are given for the oppositions of Neptune on 1995, 1996 and two nights of 1997. In this period, 759 frames were obtained during 35 nights at the Cassegrain focus of the 1.6m and the 0.6m reflectors of the LNA-Brazil. The comparison with calculated positions gives residuals with standard deviation of the order of 0.09".
144. CCD survey of galaxies. III.
ID:
ivo://CDS.VizieR/J/A+AS/107/285
Title:
CCD survey of galaxies. III.
Short Name:
J/A+AS/107/285
Date:
21 Oct 2021
Publisher:
CDS
Description:
(no description available)
145. CCD Survey of Galaxies IV
ID:
ivo://CDS.VizieR/J/A+AS/112/257
Title:
CCD Survey of Galaxies IV
Short Name:
J/A+AS/112/257
Date:
21 Oct 2021
Publisher:
CDS
Description:
Continuing a CCD survey of galaxies belonging or projected onto the Coma and Hercules Superclusters, to the A262 and Cancer clusters, we present isophote maps and photometric profiles in the Johnson system of 111 galaxies (67 in the V and B bands, 42 only in V, 2 only in B) obtained with the 2.1m telescope at San Pedro Martir (Baja California, Mexico).
146. CdC2000 Bordeaux Carte du Ciel catalogue
ID:
ivo://CDS.VizieR/I/303
Title:
CdC2000 Bordeaux Carte du Ciel catalogue
Short Name:
I/303
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the CdC2000 catalogue issued from the reduction of the complete Bordeaux Carte du Ciel zone observed at the beginning of last century with the Bordeaux astrograph. This catalogue is a positional catalogue of 344780 stars covering the declination zone +11{deg}<delta<+18{deg}. The average epoch of positions is 1914.7. The data are from the 512 Carte du Ciel plates archived at the Bordeaux Observatory and scanned with the APM Cambridge automatic measuring machine. Plates have been individually reduced using the TYCHO-2 Catalogue as astrometric reference. Astrometric standard errors are about 0.10" to 0.12" on positions and 0.6 magnitudes on photographic magnitudes. A detailed study of errors and a comparison of various reduction methods are presented in order to take into account the significant propagated errors from the reference catalogue. The CdC2000 provides positions at the epoch of the plates for 50 682 TYCHO-2 stars. The associated positions are proved to be 0.11" more precise than the positions given by the Tycho-2 catalogue at the epoch of the plates. This work is part of a program of proper motion measurements in the Bordeaux Carte du Ciel zone (PM2000, Cat. <I/300>).
147. Celestial Reference Frame at 24 and 43 GHz
ID:
ivo://CDS.VizieR/J/AJ/139/1695
Title:
Celestial Reference Frame at 24 and 43 GHz
Short Name:
J/AJ/139/1695
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present astrometric results for compact extragalactic objects observed with the Very Long Baseline Array at radio frequencies of 24 and 43GHz. Data were obtained from ten 24-hr observing sessions made over a five-year period. These observations were motivated by the need to extend the International Celestial Reference Frame (ICRF) to higher radio frequencies to enable improved deep space navigation after 2016 and to improve state-of-the-art astrometry. Source coordinates for 268 sources were estimated at 24GHz and for 131 sources at 43GHz.
148. Celestial Reference Frame at 24 and 43GHz. II
ID:
ivo://CDS.VizieR/J/AJ/139/1713
Title:
Celestial Reference Frame at 24 and 43GHz. II
Short Name:
J/AJ/139/1713
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have measured the submilliarcsecond structure of 274 extragalactic sources at 24 and 43 GHz in order to assess their astrometric suitability for use in a high-frequency celestial reference frame (CRF). Ten sessions of observations with the Very Long Baseline Array have been conducted over the course of ~5 years, with a total of 1339 images produced for the 274 sources. There are several quantities that can be used to characterize the impact of intrinsic source structure on astrometric observations including the source flux density, the flux density variability, the source structure index, the source compactness, and the compactness variability.
149. Census of Rho Oph candidate members from Gaia DR2
ID:
ivo://CDS.VizieR/J/A+A/626/A80
Title:
Census of Rho Oph candidate members from Gaia DR2
Short Name:
J/A+A/626/A80
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Ophiuchus cloud complex is one of the best laboratories to study the earlier stages of the stellar and protoplanetary disc evolution. We constructed a control sample composed of 188 bona fide Ophiuchus members. Using this sample as a reference we applied three different density-based machine learning clustering algorithms (DBSCAN, OPTICS, and HDBSCAN) to a sample drawn from the Gaia DR2 catalogue centred on the Ophiuchus cloud that contains 2300 sources covering a sky area of 38deg^2^. The clustering analysis was applied in the five astrometric dimensions defined by the three-dimensional Cartesian space and the proper motions in right ascension and declination. The three clustering algorithms systematically identify a similar set of candidate members in a main cluster with astrometric properties consistent with those of the control sample. We constructed a common sample containing 391 member candidates including 166 new objects, which have not yet been discussed in the literature. We built the SEDs for a subset of 48 objects and found a total of 41 discs.
150. Cepheids in open clusters
ID:
ivo://CDS.VizieR/J/MNRAS/434/2238
Title:
Cepheids in open clusters
Short Name:
J/MNRAS/434/2238
Date:
21 Oct 2021
Publisher:
CDS
Description:
Cepheids in open clusters (cluster Cepheids: CCs) are of great importance as zero-point calibrators of the Galactic Cepheid period-luminosity relationship (PLR). We perform an 8-dimensional all-sky census that aims to identify new bona-fide CCs and provide a ranking of membership confidence for known CC candidates according to membership probabilities. The probabilities are computed for combinations of known Galactic open clusters and classical Cepheid candidates, based on spatial, kinematic, and population-specific membership constraints. Data employed in this analysis are taken largely from published literature and supplemented by a year-round observing program on both hemispheres dedicated to determining systemic radial velocities of Cepheids. In total, we find 23 bona-fide CCs, 5 of which are candidates identified for the first time, including an overtone-Cepheid member in NGC 129. We discuss a subset of CC candidates in detail, some of which have been previously mentioned in the literature. Our results indicate unlikely membership for 7 Cepheids that have been previously discussed in terms of cluster membership. We furthermore revisit the Galactic PLR using our bona fide CC sample and obtain a result consistent with the recent calibration by Turner (2010). However, our calibration remains limited mainly by cluster uncertainties and the small number of long-period calibrators. In the near future, Gaia will enable our study to be carried out in much greater detail and accuracy, thanks to data homogeneity and greater levels of completeness.

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