- ID:
- ivo://CDS.VizieR/J/ApJ/745/56
- Title:
- Upper Sco members rotational velocities
- Short Name:
- J/ApJ/745/56
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present projected rotational velocities for 20 early-type (B8-A9) and 74 late-type (F2-M8) members of the ~5 Myr old Upper Scorpius OB Association derived from high-dispersion optical spectra obtained with the High Resolution Echelle Spectrometer on Keck I and the Magellan Inamori Kyocera Echelle on the Magellan Clay telescope. The spectroscopic sample is composed of stars and brown dwarfs with infrared signatures of circumstellar disks, both primordial and debris, and non-excess sources of comparable spectral type. We merge projected rotational velocities, accretion diagnostics, and Spitzer Space Telescope Infrared Array Camera and Multiband Imaging Photometer for Spitzer 24 {mu}m photometry to examine the relationship between rotation and circumstellar disks. The rotational velocities are strongly correlated with spectral type, a proxy for mass, such that the median vsin i for B8-A9-type stars is: 195+/-70km/s, F2-K4: 37.8+/-7.4km/s, K5-K9: 13.8^+21.3^_-8.2_km/s, M0-M5: 16.52+/-5.3km/s, and M5.5-M8: 17.72+/-8.1km/s. We find with a probability of >=0.99 that M-type stars and brown dwarfs having infrared excess suggestive of circumstellar disks rotate more slowly than their non-excess counterparts. A similar correlation is present among F2-K9-type stars, but only at the ~97% confidence level. Among the early-type (B8-A9) members, rotational velocities of the debris-disk and non-disk populations are indistinguishable. Considering the late-type (F2-M8) stars and brown dwarfs, we find a low fraction of slowly rotating, non-excess sources relative to younger star-forming regions, suggesting that most have spun up following disk dissipation. The few late-type (F2-M5) debris disk sources, which may be representative of stars that have recently dispersed their inner disks, are evenly divided between slow and moderate rotators.
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- ID:
- ivo://CDS.VizieR/J/ApJ/651/L49
- Title:
- Upper Sco OB association IRAC observations
- Short Name:
- J/ApJ/651/L49
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 4.5, 8 and 16um photometry from the Spitzer Space Telescope for 204 stars in the Upper Scorpius OB association. The data are used to investigate the frequency and properties of circumstellar disks around stars with masses between 0.1 and 20 at an age of 5Myr. We identify 35 stars that have emission at 8 or 16um in excess of the stellar photosphere.
22063. Upper Scorpius members
- ID:
- ivo://CDS.VizieR/J/other/NatAs/6.89
- Title:
- Upper Scorpius members
- Short Name:
- J/other/NatAs/6.
- Date:
- 03 Mar 2022 16:55:14
- Publisher:
- CDS
- Description:
- The nature and origin of free-floating planets (FFPs) are still largely unconstrained because of a lack of large homogeneous samples to enable a statistical analysis of their properties. So far, most FFPs have been discovered using indirect methods; microlensing surveys have proved particularly successful to detect these objects down to a few Earth masses. However, the ephemeral nature of microlensing events prevents any follow-up observations and individual characterization. Several studies have identified FFPs in young stellar clusters and the Galactic field but their samples are small or heterogeneous in age and origin. Here we report the discovery of between 70 and 170 FFPs (depending on the assumed age) in the region encompassing Upper Scorpius and Ophiuchus, the closest young OB association to the Sun. We found an excess of FFPs by a factor of up to seven compared with core-collapse model predictions, demonstrating that other formation mechanisms may be at work. We estimate that ejection from planetary systems might have a contribution comparable to that of core collapse in the formation of FFPs. Therefore, ejections due to dynamical instabilities in giant exoplanet systems must be frequent within the first 10Myr of a system's life.
- 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.
- 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}_.
- 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.
- ID:
- ivo://nasa.heasarc/upprscoxmm
- Title:
- Upper Sco XMM-Newton X-Ray Point Source Catalog
- Short Name:
- UPPRSCOXMM
- Date:
- 21 Feb 2025
- 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 <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/459/199">CDS catalog J/A+A/459/199</a> files tabled1.dat and table2.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/ugc
- Title:
- Uppsala General Catalog of Galaxies
- Short Name:
- UGC
- Date:
- 21 Feb 2025
- 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 <a href="https://cdsarc.u-strasbg.fr/ftp/cats/VII/26D/ReadMe">https://cdsarc.u-strasbg.fr/ftp/cats/VII/26D/ReadMe</a>, while the list of the affected entries is available at <a href="https://cdsarc.u-strasbg.fr/ftp/cats/VII/26D/errors.dat.gz">https://cdsarc.u-strasbg.fr/ftp/cats/VII/26D/errors.dat.gz</a>. <p> The HEASARC last updated this database table in November 2021 upon reflection that the original catalog'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 .
- 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.
- ID:
- ivo://CDS.VizieR/J/A+A/367/597
- Title:
- ups Her, phi Her & HR 7018 abundances
- Short Name:
- J/A+A/367/597
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Elemental abundances analyses are performed for the Mercury-Manganese stars {upsilon} Her, {phi} Her, and HR 7018 consistent with previous studies of this series using spectrograms obtained with Reticon and CCD detectors. Comparisons of the first two analyses with those performed using coadded photographic plates show the general consistency of the derived elemental abundances. For {upsilon} Her and for {phi} Her, abundances were newly found for O, and for Al, V, Zn, and Ce, respectively. HR 7018 is discovered to be a single-lined spectroscopic binary. Its Sc abundance is the smallest of any class member with derived abundances and its Sr abundance the largest of any known HgMn star. A correlation analysis of the most complete abundance sets for 20 HgMn stars shows that the abundances of some elements are correlated with one another and some are functions of the stellar effective temperature.
