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191. Galaxy coordinates. II
ID:
ivo://CDS.VizieR/J/A+AS/140/89
Title:
Galaxy coordinates. II
Short Name:
J/A+AS/140/89
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using images of the Digitized Sky Survey we measured coodinates for 17298 galaxies having poorly defined coordinates. As a control, we measured with the same method 1522 galaxies having accurate coordinates. The comparison with our own measurements shows that the accuracy of the method is about 6 arcsec on each axis (RA and DEC).
192. Galilean moons & Jupiter positions
ID:
ivo://CDS.VizieR/J/other/SoSyR/50.344
Title:
Galilean moons & Jupiter positions
Short Name:
J/other/SoSyR/50
Date:
21 Oct 2021
Publisher:
CDS
Description:
Observational results are presented for Jupiter and its Galilean moons from the Normal Astrograph at Pulkovo Observatory in 2013-2015. The following data are obtained: 154 positions of the Galilean satellites and 47 calculated positions of Jupiter in the system of the UCAC4 (ICRS, J2000.0) catalogue; the differential coordinates of the satellites relative to one another are determined. The mean errors of the satellites normal places in right ascension and declination over the entire observational period are, respectively: (eps)RA=0.0065" and (eps)DE=0.0068", and their standard deviations are (sigm)RA=0.0804" and (sigm)DE=0.0845". The equatorial coordinates are compared with planetary and satellite motion theories. The average (O-C) residuals in the two coordinates relative to the motion theories are 0.05" or less. The best agreement with the observations is achieved by a combination of the EPM2011m and V. Lainey-V.2.0|V1.1 motion theories; the average (O-C) residuals are 0.03" or less. The (O-C) residuals for the features of the positions of Io and Ganymede are comparable with measurement errors. Jupiter's positions calculated from the observations of the satellites and their theoretical jovicentric coordinates are in good agreement with the motion theories. The (O-C) residuals for Jupiter's coordinates are, on average, 0.027" and -0.025" in the two coordinates.
193. Galilean moons positions
ID:
ivo://CDS.VizieR/J/other/SoSyR/52.312
Title:
Galilean moons positions
Short Name:
J/other/SoSyR/52
Date:
21 Oct 2021
Publisher:
CDS
Description:
Results of the Galilean moons observationals taken with Normal Astrograph of the Pulkovo Observatory in 2016-2017 are presented. 761 positions of the Galilean moons of Jupiter in the system of the Gaia DR1 catalog (ICRF, J2000.0) and 854 differential coordinates of the satellites relative to each other were obtained. The mean errors in the satellites' normal places and the corresponding root-mean-square deviations are (eps)RA=0.0020", (eps)DE=0.0027", (sigm)RA=0.0546", and (sigm)DE=0.0757". The equatorial coordinates of the moons are compared to the motion theories of planets and satellites. On average, the (O-C) residuals in the both coordinates relative to the motion theories are less than 0.031". The best agreement with observations is achieved by a combination of the EPM2015 and V. Lainey-V.2.0|V1.1 motion theories, which yields the average (O-C) residuals of approximately 0.02". Peculiarities in the behavior of the (O-C) residuals and error values in Ganymede have been noticed.
194. Galilean satellites & Jupiter positions
ID:
ivo://CDS.VizieR/J/other/SoSyR/49.383
Title:
Galilean satellites & Jupiter positions
Short Name:
J/other/SoSyR/49
Date:
21 Oct 2021
Publisher:
CDS
Description:
For observational period of 2009-2011 we have obtained 140 positions of Galilean satellites and 42 calculated positions of Jupiter in the system of UCAC4 catalogue (ICRS, J2000.0). Accuracy estimation gives error of mean position as 0.02-0.04". The resulting equatorial coordinates satellites were compared with the eight contemporary theories of the motion of planets and satellites. On average, the (O-C) residuals in both coordinates do not exceed 0.08" relative to all theories of motion. Comparison of the calculated equatorial coordinates of Jupiter (were obtained from observations of galilean satellites) with the INPOP10 theory of planetary motion has shown satisfactory results. The average deviations were obtained respectively (O-C)RA=0.040" and (O-C)DE=-0.053". This work was supported by the Program 22 of the Presidium of RAS and RFBR grant (12-02-00675-a).
195. General Catalogue of Stars
ID:
ivo://CDS.VizieR/I/180
Title:
General Catalogue of Stars
Short Name:
I/180
Date:
21 Oct 2021
Publisher:
CDS
Description:
The general Catalogue reported here has been Compiled on the basis of the preliminary catalogues consisting of the long series observations of the fundamental programs (mainly of FK4 stars) of the Mark I photoelectric astrolabe of Shaanxi Astronomical Observatory and Mark II photoelectric astrolobes of Beijing, Shanghai and Yunnan Astronomical Observatories, together with a large amount of observations of catalogue stars carried out in Beijing, Shanghai and Shaanxi, as well as 4 preliminary catalogues of Danjon's astrolabes derived from the observations of OPL No.14 of Shanghai, No.30 of Beijing and No.29 of Wuchang. With magnitudes ranging from 0.1 to 7.2, the GCPA consists of 1579 stars. The declinations are from -3.6 degree to 68.8 degree, in which 642 are FK4 stars. The mean precisions of position corrections are 3.3 ms and 0.058" in right ascension and declination, respectively. The mean epoch of GCPA is 1987.8.
196. General Catalogue of 33342 stars (GC)
ID:
ivo://CDS.VizieR/I/113A
Title:
General Catalogue of 33342 stars (GC)
Short Name:
I/113A
Date:
21 Oct 2021
Publisher:
CDS
Description:
The GC is a catalog of standard positions and proper motions for (all) stars brighter than magnitude 7, extending from the north to south celestial poles. Several thousand additional stars promising to yield reasonably accurate proper motions were included in the catalog. The objectives of the work were to provide standard positions and motions of accuracy limited only by the character and abundance of the observational material upon which the data were based and thus to provide a rich supply of data to promote research in many astronomical fields. The machine version of the GC includes both The Henry Draper Catalogue and Durchmusterung identifications for all stars, although the published GC contains only one or the other. The 1985 version corrected many errors present in a previous machine version and included probable errors for the positions and centennial proper motions (not present in the previous version). In this version decimal points have been aligned for all but a very few of the secular variations and third terms. These quantities are given with the same precision as in the printed catalog, and the coded spectral types have been omitted. The following quantities are included in the machine but not the published version: galactic coordinates and DM numbers. The following data are in the published but not the machine version: centennial increments of proper motion in right ascension and declination, probable errors of the right ascension and declination at 1950.0, and remarks. The documentation supplied with the machine catalog gives a byte-by-byte format description, indigenous catalog characteristics, code explanation tables, and changes incorporated to produce this and previous Astronomical Data Center versions.
197. Geneva-Copenhagen Survey of Solar neighbourhood
ID:
ivo://CDS.VizieR/V/117A
Title:
Geneva-Copenhagen Survey of Solar neighbourhood
Short Name:
V/117A
Date:
21 Oct 2021
Publisher:
CDS
Description:
(from paper II, 2007) Ages, metallicities, space velocities, and Galactic orbits of stars in the Solar neighbourhood are fundamental observational constraints on models of galactic disk evolution. Understanding and minimising systematic errors and sample selection biases in the data is crucial for their interpretation. We aim to consolidate the calibrations of uvbyb photometry into T_eff_, [Fe/H], distance, and age for F and G stars and rediscuss the results of the Geneva-Copenhagen Survey (GCS, Nordstrom et al., 2004, paper I) in terms of the evolution of the disk. We use recent V-K photometry, angular diameters, high-resolution spectroscopy, Hipparcos parallaxes, and extensive numerical simulations to re-examine and verify the temperature, metallicity, distance, and reddening calibrations for the uvbyb system. We also highlight the selection effects inherent in the apparent-magnitude limited GCS sample. We substantially improve the T_eff_ and [Fe/H] calibrations for early F stars, where spectroscopic temperatures have large systematic errors. A slight offset of the GCS photometry and the non-standard helium abundance of the Hyades invalidate its use for checking metallicity or age scales; however, the distances, reddenings, metallicities, and age scale for GCS field stars require minor corrections only. Our recomputed ages are in excellent agreement with the independent determinations by Takeda et al. (2007ApJS..168..297T), indicating that isochrone ages can now be reliably determined. The revised G-dwarf metallicity distribution remains incompatible with closed-box models, and the age-metallicity relation for the thin disk remains almost flat, with large and real scatter at all ages sigma_intrinsic=0.20 dex). Dynamical heating of the thin disk continues throughout its life; specific in-plane dynamical effects dominate the evolution of the U and V velocities, while the W velocities remain random at all ages. When assigning thick and thin-disk membership for stars from kinematic criteria, parameters for the oldest stars should be used to characterise the thin disk.
198. Geneva-Copenhagen Survey of Solar neighbourhood III
ID:
ivo://CDS.VizieR/V/130
Title:
Geneva-Copenhagen Survey of Solar neighbourhood III
Short Name:
V/130
Date:
21 Oct 2021
Publisher:
CDS
Description:
Ages, chemical compositions, velocity vectors, and Galactic orbits for stars in the solar neighbourhood are fundamental test data for models of Galactic evolution. The Geneva-Copenhagen Survey of the Solar neighbourhood (Nordstrom et al. 2004A&A...418..989N; GCS), a magnitude-complete, kinematically unbiased sample of 16,682 nearby F and G dwarfs, is the largest available sample with complete data for stars with ages spanning that of the disk. We aim to improve the accuracy of the GCS data by implementing the recent revision of the Hipparcos parallaxes. The new parallaxes yield improved astrometric distances for 12,506 stars in the GCS. We also use the parallaxes to verify the distance calibration for uvbyHbeta photometry by Holmberg et al. (2007A&A...475..519H; GCS II, Cat. VI/117). We add new selection criteria to exclude evolved cool stars giving unreliable results and derive distances for 3,580 stars with large parallax errors or not observed by Hipparcos. We also check the GCS II scales of T_eff_ and [Fe/H] and find no need for change. From the new distances we compute revised Mv, U, V, W, and Galactic orbital parameters for 13,520 GCS stars. We also recompute stellar ages with the new values of Mv from the Padova stellar evolution models used in GCS I-II, and compare them with ages from the Yale-Yonsei and Victoria-Regina models. Finally, we compare the observed age-velocity relation in W with three simulated disk heating scenarios to show the potential of the data. With these revisions, the basic data for the GCS stars should now be as reliable as is possible with existing techniques. Further improvement must await consolidation of the T_eff_ scale from angular diameters and fluxes, and the Gaia trigonometric parallaxes. We discuss the conditions for improving computed stellar ages from new input data, and for distinguishing different disk heating scenarios from data sets of the size and precision of the GCS.
199. Geneva-Copenhagen survey re-analysis
ID:
ivo://CDS.VizieR/J/A+A/530/A138
Title:
Geneva-Copenhagen survey re-analysis
Short Name:
J/A+A/530/A138
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a re-analysis of the Geneva-Copenhagen survey, benefiting from the infrared flux method to improve upon the accuracy of the derived stellar effective temperatures and using the latter to build a consistent and improved metallicity scale. Metallicities are calibrated on high-resolution spectroscopy and checked against four open clusters and a moving group, showing excellent consistency. The new temperature and metallicity scales provide a better match to theoretical isochrones, which are used for a Bayesian analysis of stellar ages. With respect to previous analyses, our stars are on average 100K hotter and 0.1dex more metal rich, shifting the peak of the metallicity distribution function around the solar value. From Stromgren photometry we are able to derive for the first time a proxy for [Fe] abundances, which enables for a tentative dissection of the chemical thin and thick disc. We find evidence for the latter being composed of an old, mildly but systematically alpha-enhanced population extending to super solar metallicities, in agreement with spectroscopic studies. Our revision offers the largest existing kinematically unbiased sample of the solar neighbourhood that contains full information on kinematics, metallicities and ages and thus provides better constraints on the physical processes relevant in the build-up of the Milky Way disc, enabling a better understanding of the Sun in a Galactic context.
200. 1.4GHz First Look Survey (FLS)
ID:
ivo://CDS.VizieR/J/A+A/424/371
Title:
1.4GHz First Look Survey (FLS)
Short Name:
J/A+A/424/371
Date:
21 Oct 2021
Publisher:
CDS
Description:
The First Look Survey (FLS) is the first scientific product to emerge from the Spitzer Space Telescope. A small region of this field (the verification strip) has been imaged very deeply, permitting the detection of cosmologically distant sources. We present Westerbork Synthesis Radio Telescope (WSRT) observations of this region, encompassing a 1 sq. deg field, centred on the verification strip (J2000 RA=17:17:00.00, DE=59:45:00.000). The radio images reach a noise level of 8.5 microJy per beam - the deepest WSRT image made to date. We summarise here the first results from the project, and present the final mosaic image, together with a list of detected sources. The effect of source confusion on the position, size and flux density of the faintest sources in the source catalogue are also addressed. The results of a serendipitous search for HI emission in the field are also presented. Using a subset of the data, we clearly detect HI emission associated with four galaxies in the central region of the FLSv. These are identified with nearby, massive galaxies.

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