- ID:
- ivo://CDS.VizieR/I/251
- Title:
- VLBI International Celestial Reference Frame (ICRF)
- Short Name:
- I/251
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- of the 1998AJ....116..516M paper: A quasi-inertial reference frame is defined based on the radio positions of 212 extragalactic sources distributed over the entire sky. The positional accuracy of these sources is better than about 1mas in both coordinates. The radio positions are based upon a general solution for all applicable dual-frequency 2.3 and 8.4GHz Mark III very long baseline interferometry data available through the middle of 1995, consisting of 1.6 million pairs of group delay and phase delay rate observations. Positions and details are also given for an additional 396 objects that either need further observation or are currently unsuitable for the definition of a high-accuracy reference frame. The final orientation of the frame axes has been obtained by a rotation of the positions into the system of the International Celestial Reference System and is consistent with the FK5 J2000.0 optical system, within the limits of the link accuracy. The resulting International Celestial Reference Frame has been adopted by the International Astronomical Union as the fundamental celestial reference frame, replacing the FK5 optical frame as of 1998 January 1.
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- ID:
- ivo://CDS.VizieR/J/A+A/603/A3
- Title:
- VLT/NaCo Large program. IV. Statistical analysis
- Short Name:
- J/A+A/603/A3
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Understanding the formation and evolution of giant planets (>1M_Jup_) at wide orbital separation (>5AU) is one of the goals of direct imaging. Over the past 15 years, many surveys have placed strong constraints on the occurrence rate of wide-orbit giants, mostly based on non-detections, but very few have tried to make a direct link with planet formation theories. In the present work, we combine the results of our previously published VLT/NaCo large program with the results of 12 past imaging surveys to constitute a statistical sample of 199 FGK stars within 100 pc, including three stars with sub-stellar companions. Using Monte Carlo simulations and assuming linear flat distributions for the mass and semi-major axis of planets, we estimate the sub-stellar companion frequency to be within 0.75-5.70% at the 68% confidence level (CL) within 20-300AU and 0.5-75M_Jup_, which is compatible with previously published results. We also compare our results with the predictions of state-of-the-art population synthesis models based on the gravitational instability (GI) formation scenario with and without scattering. We estimate that in both the scattered and non-scattered populations, we would be able to detect more than 30% of companions in the 1-75M_Jup_ range (95% CL). With the three sub-stellar detections in our sample, we estimate the fraction of stars that host a planetary system formed by GI to be within 1.0-8.6% (95% CL). We also conclude that even though GI is not common, it predicts a mass distribution of wide-orbit massive companions that is much closer to what is observed than what the core accretion scenario predicts. Finally, we associate the present paper with the release of the Direct Imaging Virtual Archive (DIVA), a public database that aims at gathering the results of past, present, and future direct imaging surveys.
- ID:
- ivo://CDS.VizieR/I/40
- Title:
- WASHINGTON 20 Catalog
- Short Name:
- I/40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue contains the two parts: the 9989 first stars are the standard and intermediary stars, +90 to -36 degrees of declination, observed in the years 1913 to 1926, and reduced without proper motion to the equinox 1920.0 ; the second part (stars numbered 9990 to 10571) are 582 miscellaneous stars.
- ID:
- ivo://CDS.VizieR/VI/90
- Title:
- Wide-Field Plate Database
- Short Name:
- VI/90
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Wide-Field Plate Database (WFPDB) contains the descriptive information for the astronomical wide-field (~>1deg.) photographic observations stored in numerous archives all over the world. When finished it will provide an on-line access to the information for about 2 million observations from nearly 300 archives, obtained since the end of last century. Presently the WFPDB includes data for about 330 000 observations from 57 plate catalogues. About 120 000 observations more from 32 plate catalogs are in preparation to be included in the database. The WFPDB provides for each observation information for the corresponding archive, the parameters of the observational instrument, the observation parameters (position on sky, observation time, object name, method, exposure time, emulsion type, filter type, spectral band, plate size), as well as data on the plate quality, comments, and observers. Data on the plate availability and digitization will be supplemented in the WFPDB in the future.
- ID:
- ivo://CDS.VizieR/I/334
- Title:
- W1J00 and W2J00 Transit Circle Catalogs
- Short Name:
- I/334
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- W1J00. We present the result of observations made with the Six-inch Transit Circle in Washington, D.C., between September 1977 and July 1982. The catalog, called W1J00, contains mean positions of 7267 stars, all but five are north of -30 degrees declination, and 4383 observations of solar system objects. Positions of stars are for mean epoch of observation, on equator and equinox J2000.0. Positions of solar system objects are apparent places. Error estimates are about 100mas per coordinate for the majority of stars. W2J00. We present the result of observations made with the Six-inch Transit Circle in Washington, D.C. and the Seven-inch Transit Circle at the Black Birch station near Blenheim, New Zealand between April 1985 and February 1996. The catalog, called W2J00, contains mean positions of 44,395 globally distributed stars, 5048 observations of the planets, and 6518 observations of the brighter minor planets. Positions of stars are for mean epoch of observation, on equator and equinox J2000.0. Positions of solar system objects are apparent places. Error estimates are about 75mas per coordinate for the majority of stars.
- ID:
- ivo://CDS.VizieR/J/A+A/565/A117
- Title:
- X-Shooter Spectral Library (XSL). DR1
- Short Name:
- J/A+A/565/A117
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first release of XSL, the X-Shooter Spectral Library observed at the European Southern Observatory (ESO). This release contains 237 stars spanning the wavelengths 3000-10200{AA} observed at a resolving power R~10000. Telluric standard stars used to correct the Earth atmospheric contamination are presented as well.
- ID:
- ivo://CDS.VizieR/J/A+A/634/A133
- Title:
- X-Shooter Spectral Library (XSL). DR2
- Short Name:
- J/A+A/634/A133
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the second data release (DR2) of the X-Shooter Spectral Library (XSL), which contains all the spectra obtained over the six semesters of that program. This release supersedes our first data release from 2014, with a larger number of spectra (813 observations of 666 stars) and with a more extended wavelength coverage as the data from the near-infrared arm of the X-Shooter spectrograph are now included. The DR2 spectra then consist of three segments that were observed simultaneously and, if combined, cover the range between 300nm and 2.45um at a spectral resolving power close to R=10000. The spectra were corrected for instrument transmission and telluric absorption, and they were also corrected for wavelength-dependent flux-losses in 85% of the cases. On average, synthesized broad-band colors agree with those of the MILES library and of the combined IRTF and Extended IRTF libraries to within 1%. The scatter in these comparisons indicates typical errors on individual colors in the XSL of 2-4%. The comparison with 2MASS point source photometry shows systematics of up to 5% in some colors, which we attribute mostly to zero-point or transmission curve errors and a scatter that is consistent with the above uncertainty estimates. The final spectra were corrected for radial velocity and are provided in the rest-frame (with wavelengths in air). The spectra cover a large range of spectral types and chemical compositions (with an emphasis on the red giant branch), which makes this library an asset when creating stellar population synthesis models or for the validation of near-ultraviolet to near-infrared theoretical stellar spectra across the Hertzsprung-Russell diagram.
- ID:
- ivo://CDS.VizieR/J/A+AS/118/239
- Title:
- Yunnan Observatory photoelectric astrolabe catalogue
- Short Name:
- J/A+AS/118/239
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The positions of 53 FK5, 70 FK5 Extension and 486 GC stars are given for equator and the equinox J2000.0 and for the mean observation epoch of each star which are determined with the photoelectric astrolabe of Yunnan Observatory. The internal mean errors in right ascension and declination are 0.046" and 0.059", respectively. The mean observation epoch is 1989.51.
