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16451. Upper Scorpius OB association Lithium survey
ID:
ivo://CDS.VizieR/J/A+A/333/619
Title:
Upper Scorpius OB association Lithium survey
Short Name:
J/A+A/333/619
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of an intermediate resolution spectroscopic survey for pre-main sequence (PMS) stars in the Upper Scorpius OB association. In a 160 square-degree area we were able to identify 39 new PMS stars by follow up observations of X-ray selected stars with the multi object spectrograph FLAIR at the UK Schmidt Telescope. We also investigated the completeness of our X-ray selected sample by observing more than 100 stars that were not detected as X-ray sources, but have proper motions indicating membership to Upper Sco. While the new X-ray selected PMS stars with known proper motions have kinematics consistent with membership, none of the X-ray quiet proper motion candidates is a PMS star. We conclude that our X-ray selected sample of PMS stars seems to be rather complete. For stars in the magnitude interval 11.5<~B<~13.5 we derive a conservative lower limit of 75% completeness.
16452. Upper Scorpius OB association Lithium survey. II.
ID:
ivo://CDS.VizieR/J/AJ/124/404
Title:
Upper Scorpius OB association Lithium survey. II.
Short Name:
J/AJ/124/404
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate the stellar population and star formation history of the Upper Scorpius OB association, the most nearby region of recent massive star formation, over the full stellar mass range from 0.1 to 20M_{sun}_. The first part of this paper describes an extension of our large spectroscopic survey (Preibisch et al., published in 2001, Cat. <J/AJ/121/1040>) for low-mass pre-main-sequence (PMS) stars in Upper Scorpius. Using the multiobject spectrograph 2dF at the Anglo-Australian Telescope, we obtained spectra of 469 stars with magnitudes R=12.5-18.0 in a 6{deg}^2^ area, on he nights of 2001 May 16-17. Among these, we find 68 new PMS stars, nearly all of them M-type stars, by their strong lithium absorption lines. The total area covered by our 2dF survey is now 9 deg2 and contains 166 new PMS stars. Combining these results with our earlier investigation (Preibisch & Zinnecker, 1999AJ....117.2381P) yields a sample of 250 PMS stars in the mass range ~0.2 to ~2M_{sun}_.
16453. Upper Scorpius spectroscopy and photometry
ID:
ivo://CDS.VizieR/J/AJ/160/44
Title:
Upper Scorpius spectroscopy and photometry
Short Name:
J/AJ/160/44
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have refined the census of stars and brown dwarfs in the Upper Sco association (~10Myr, ~145pc) by (1) updating the selection of candidate members from our previous survey to include the high-precision astrometry from the second data release of Gaia, (2) obtaining spectra of a few hundred candidate members to measure their spectral types and verify their youth, and (3) assessing the membership (largely with Gaia astrometry) of 2020 stars toward Upper Sco that show evidence of youth in this work and previous studies. We arrive at a catalog of 1761 objects that are adopted as members of Upper Sco. The distribution of spectral types among the adopted members is similar to those in other nearby star-forming regions, indicating a similar initial mass function. In previous studies, we have compiled mid-infrared photometry from the Wide-field Infrared Survey Explorer and the Spitzer Space Telescope for members of Upper Sco and used those data to identify the stars that show evidence of circumstellar disks; we present the same analysis for our new catalog of members. As in earlier work, we find that the fraction of members with disks increases with lower stellar masses, ranging from <~10% for >1M{sun} to ~22% for 0.01-0.3M{sun}. Finally, we have estimated the relative ages of Upper Sco and other young associations using their sequences of low-mass stars in M_G_RP__ versus G_BP_-G_RP_. This comparison indicates that Upper Sco is a factor of two younger than the {beta}Pic association (21-24Myr) according to both nonmagnetic and magnetic evolutionary models.
16454. Upper Sco XMM-Newton X-Ray Point Source Catalog
ID:
ivo://nasa.heasarc/upprscoxmm
Title:
Upper Sco XMM-Newton X-Ray Point Source Catalog
Short Name:
UPPRSCOXMM
Date:
08 Nov 2024
Publisher:
NASA/GSFC HEASARC
Description:
The authors studied the X-ray emission from young stars by analyzing the deep (a ~53 ks exposure centered at a J2000.0 RA and Dec of 16 14 00.0, -23 00 00 and a ~43 ks exposure at 15 56 25.0, -23 37 47) XMM-Newton observations of two regions of the Upper Scorpius (USco) subgroup of the Scorpius-Centaurus (Sco-Cen) association which is estimated to have an age of 5 Myr. Portions of the USco association were observed in the optical with the CTIO Curtis Schmidt telescope and the Danish 1.54m telescope. This table contains all the X-ray sources detected in the two XMM-Newton observations, as well as their near-IR counterparts from the 2MASS and DENIS catalogs, and their optical counterparts from the CTIO and Danish 1.54 m observations. Based on the near-infrared and optical photometry, 22 Upper Scorpius photometric members have been identified among the 224 detected X-ray sources. This table was created by the HEASARC in March 2007 based on &lt;a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/459/199"&gt;CDS catalog J/A+A/459/199&lt;/a&gt; files tabled1.dat and table2.dat. This is a service provided by NASA HEASARC .
16455. Uppsala General Catalog of Galaxies
ID:
ivo://nasa.heasarc/ugc
Title:
Uppsala General Catalog of Galaxies
Short Name:
UGC
Date:
08 Nov 2024
Publisher:
NASA/GSFC HEASARC
Description:
The Uppsala General Catalogue of Galaxies (UGC) is an essentially complete catalog of galaxies to a limiting diameter of 1.0 arcminute and/or to a limiting apparent magnitude of 14.5 on the blue prints of the Palomar Observatory Sky Survey (POSS). Coverage is limited to the sky north of declination -02.5 degrees. Galaxies smaller than 1.0 arcminute in diameter but brighter than 14.5 mag may be included from the Catalogue of Galaxies and of Clusters of Galaxies (CGCG, Zwicky et al. 1961-1968); all such galaxies in the CGCG are included in the UGC. The galaxies are numbered in order of their 1950.0 right ascension values. The catalog contains descriptions of the galaxies and their surrounding areas, plus conventional system classifications and position angles for flattened galaxies. Galaxy diameters on both the blue and red POSS prints are included and the classifications and descriptions are given in such a way as to provide as accurate an account as possible of the appearance of the galaxies on the prints. Only the data portion of the published UGC is included in the machine-readable version, notice. For additional details regarding the classifications, measurement of apparent magnitudes, and data content, the source reference should be consulted. This database table was first ingested by the HEASARC in September 2000 based on a machine-readable version of the UGC obtained from the ADC (ADC Catalog VII/26D). This latter version was a corrected and modified version of the original magnetic tape version of the UGC. A list of the types of changes and modifications made by the ADC is available at &lt;a href="https://cdsarc.u-strasbg.fr/ftp/cats/VII/26D/ReadMe"&gt;https://cdsarc.u-strasbg.fr/ftp/cats/VII/26D/ReadMe&lt;/a&gt;, while the list of the affected entries is available at &lt;a href="https://cdsarc.u-strasbg.fr/ftp/cats/VII/26D/errors.dat.gz"&gt;https://cdsarc.u-strasbg.fr/ftp/cats/VII/26D/errors.dat.gz&lt;/a&gt;. &lt;p&gt; The HEASARC last updated this database table in November 2021 upon reflection that the original catalog&#39;s coordinates were B1950 (instead of J1950, as originally assumed by the HEASARC). Due to the precision of the coordinates in this catalog, the difference is negligible. This is a service provided by NASA HEASARC .
16456. Uppsala General Catalogue of Galaxies (UGC)
ID:
ivo://CDS.VizieR/VII/26D
Title:
Uppsala General Catalogue of Galaxies (UGC)
Short Name:
VII/26D
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Uppsala General Catalogue of Galaxies (UGC) is an essentially complete catalogue of galaxies to a limiting diameter of 1.0' and/or to a limiting apparent magnitude of 14.5 on the blue prints of the Palomar Observatory Sky Survey (POSS). Coverage is limited to the sky north of declination -02.5degrees. Galaxies smaller than 1.0' in diameter but brighter than 14.5 mag may be included from the Catalogue of Galaxies and of Clusters of Galaxies (CGCG, Zwicky et al. 1961-1968); all such galaxies in the CGCG are included in the UGC. The galaxies are ordered by 1950 right ascension. The catalogue contains descriptions of the galaxies and their surrounding areas, plus conventional system classifications and position angles for flattened galaxies. Galaxy diameters on both the blue and red POSS prints are included and the classifications and descriptions are given in such a way as to provide as accurate an account as possible of the appearance of the galaxies on the prints. Only the data portion of the published UGC is included in the machine-readable version. The order of the records is strictly by UGC number; i.e., the Addenda records follow their main catalogue counterparts in the file. The colons (indicating uncertainty) and various other codes (parentheses, brackets) are not included in the machine-readable version of the catalogue. Several possible improvements to the catalogue might consist of adding codes corresponding to the published version, a second file containing abbreviations and terminology and a third file with the extensive notes. It would also be important to add an asterisk or some other code to data records having a note in the proposed third file. This document describes the machine-readable version of the UGC as distributed by the Astronomical Data Centers. It is intended to enable users to read and process the data without problems or guesswork. For additional details regarding the classifications, measurement of apparent magnitudes, and data content, the source reference should be consulted. A copy of this document should accompany any machine-readable copy of the catalogue.
16457. {upsilon} Andromedae system with HST
ID:
ivo://CDS.VizieR/J/ApJ/715/1203
Title:
{upsilon} Andromedae system with HST
Short Name:
J/ApJ/715/1203
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have used high-cadence radial velocity (RV) measurements from the Hobby-Eberly Telescope with existing velocities from the Lick, Elodie, Harlan J. Smith, and Whipple 60" telescopes combined with astrometric data from the Hubble Space Telescope Fine Guidance Sensors to refine the orbital parameters and determine the orbital inclinations and position angles of the ascending node of components {upsilon} And A c and d. With these inclinations and using M*=1.31M_{sun}_ as a primary mass, we determine the actual masses of two of the companions: {upsilon} And A c is 13.98^+2.3^_-5.3_M_Jup_, and {upsilon} And A d is 10.25^+0.7^_-3.3_M_Jup_. These measurements represent the first astrometric determination of mutual inclination between objects in an extrasolar planetary system, which we find to be 29.9+/-1{deg}. The combined RV measurements also reveal a long-period trend indicating a fourth planet in the system. We investigate the dynamic stability of this system and analyze regions of stability, which suggest a probable mass of {upsilon} And A b. Finally, our parallaxes confirm that u And B is a stellar companion of {upsilon} And A.
16458. Uranometria Argentina catalog of bright southern stars
ID:
ivo://CDS.VizieR/V/135A
Title:
Uranometria Argentina catalog of bright southern stars
Short Name:
V/135A
Date:
21 Oct 2021
Publisher:
CDS
Description:
In 1879 Benjamin Apthorp Gould published in Buenos Aires, Argentina, the Uranometria Argentina catalog of 7756 stars south of declination +10 degrees. This included all those stars he considered magnitude 7 or brighter and some fainter stars which are close companions to brighter stars or to each other and have combined magnitude 7 or brighter. Star positions are in 1875 coordinates, and constellation boundaries also in 1875 coordinates were defined within the aforementioned declination range. With only a few small changes these were incorporated into the boundaries adopted by the IAU in 1930 and subsequently universally accepted. In terms of accurate photoelectric magnitude measurements the Uranometria Argentina is nearly complete to magnitude 6.5 in its declination range. In each constellation the individual stars considered to be magnitude 7 and brighter were numbered in sequence of increasing right ascension in 1875 coordinates, except that in a few cases this sequence was somewhat adjusted so that stars close together could be listed on adjacent lines of text. The numbering system is analogous to that in the Flamsteed Catalogus Brittanicus and now widely used. Star numbers from the Uranometria Argentina rarely appear in the 21st century despite the potential utility of their use. They were included in the American Ephemeris and Nautical Almanac until 1978, and in the FK5 catalog until 1999, always with the letter G following the number in the Uranometria Argentina catalog. This serves to distinguish Flamsteed numbers with no following letters from Gould numbers, and is utilized in this presentation and recommended for general use. The file catalog.dat includes every star in the original Uranometria Argentina. In the original the constellations were presented in sequence of increasing distance from the south pole and numbered accordingly. For the convenience of 21st century astronomers the constellations are presented here by alphabetical sequence in constellation name and the stars in each constellation in the same sequence as in the original. A separate file notes.txt includes a large number of notes for individual stars and for groups of stars recognized in the original catalog as belonging together. Each note is referenced by an asterisk * in the file catalog.dat. Columns 43-63 provide J2000 coordinates and cross identifications from the Flamsteed, HD, and SAO catalogs for the stars and have been added by the author of this data set. Columns 82-154 have been copied verbatim from the Uranometria Argentina catalogue, except that where asterisks are shown errors in the original printed catalogue have been corrected and the originally published values are stated in the notes. Two publications state corrections to the printed Uranometria Argentina. These are by B.A. Gould, Astronomische Nachrichten 116, 379-382 (1887AN....116..379G), and by T. W. Backhouse, Astronomical Journal 12, 112 (1892AJ.....12Q.112B). All of these, and a few others, mostly typographical misprints found by the present author, are presented in this digital version.
16459. Uranus & Neptune topocentric positions
ID:
ivo://CDS.VizieR/J/other/OAP/29.155
Title:
Uranus & Neptune topocentric positions
Short Name:
J/other/OAP/29.1
Date:
21 Oct 2021
Publisher:
CDS
Description:
Catalogs of 145 astrometric positions of Uranus and 4 its moons U1-U4 and 62 positions of Neptune and Triton have been compiled with Tycho-2 as a reference frame from photographic observations obtained at the Main Astronomical Observatory, National Academy of Sciences of Ukraine, in 1963-1990. Astronegatives have been digitized with an Epson Expression 10000XL commercial scanner in 16-bit grayscale with a resolution of 1200 dpi. Reduction has been performed in the LINUX-MIDAS-ROMAFOT software supplemented with additional modules for the precise positional determination. The internal positional accuracy of the reduction is 0.04-0.25" for both coordinates and 0.21-0.65m for photographic magnitudes of the Tycho-2 catalog. Gallery of plate images used for catalogs: http://gua.db.ukr-vo.org/catalog_gallery.php?catn=neptun_1963_1990 http://gua.db.ukr-vo.org/catalog_gallery.php?catn=uran_1963_1990
16460. URAT1 Catalog
ID:
ivo://CDS.VizieR/I/329
Title:
URAT1 Catalog
Short Name:
I/329
Date:
21 Oct 2021
Publisher:
CDS
Description:
URAT is a follow-up project to the successful UCAC project using the same astrograph but with a much larger focal plane array and a bandpass shifted further to the red. Longer integration times and more sensitive, backside CCDs allowed for a substantial increase in limiting magnitude, resulting in about 4-fold increase in the average number of stars per square degree as compared to UCAC. Additional observations with an objective grating largely extend the dynamic range to include observations of stars as bright as about 3rd magnitude. Multiple sky overlaps per year result in a significant improvement in positional precision as compared to UCAC. A URAT1 release paper for the Astronomical Journal is in preparation. URAT1 is an observational catalog at a mean epoch between 2012.3 and 2014.6; ot covers the magnitude range 3 to 18.5 in R-band, with a positional precision of 5 to 40 mas. It covers most of the northern hemisphere and some areas down to -24.8{deg} in declination.

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