- ID:
- ivo://CDS.VizieR/J/ApJ/868/32
- Title:
- A large moving group within the LCC association
- Short Name:
- J/ApJ/868/32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Scorpius-Centaurus is the nearest OB association, and its hundreds of members are divided into subgroups, including the Lower Centaurus Crux (LCC). Here we study the dynamics of the LCC area. We report the revelation of a large moving group containing more than 1800 intermediate- and low-mass young stellar objects and brown dwarfs that escaped identification until Gaia DR2 allowed a kinematic and photometric selection to be performed. We investigate the stellar and substellar content of this moving group using the Gaia DR2 astrometric and photometric measurements. The median distance of the members is 114.5pc, and 80% lie between 102 and 135pc from the Sun. Our new members cover a mass range of 0.02-5M_{sun}_ and add up to a total mass of about 700M_{sun}_. The present-day mass function follows a log-normal law with m_c_=0.22M_{sun}_ and {sigma}=0.64. We find more than 200 brown dwarfs in our sample. The star formation rate had its maximum of 8x10^-5^M_{sun}_/yr about 9Myr ago. We grouped the new members into four denser subgroups, which have increasing age from 7 to 10Myr, surrounded by "free-floating" young stars with mixed ages. Our isochronal ages, now based on accurate parallaxes, are compatible with several earlier studies of the region. The whole complex is presently expanding, and the expansion started between 8 and 10Myr ago. Two hundred members show infrared excess compatible with circumstellar disks from full to debris disks. This discovery provides a large sample of nearby young stellar and substellar objects for disk and exoplanet studies.
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Search Results
- ID:
- ivo://CDS.VizieR/I/223
- Title:
- Algiers AC Zone Data Reduced to ACRS
- Short Name:
- I/223
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The U.S. Naval Observatory is in the process of making new reductions of the Astrographic Catalogue (AC) using a modern reference system, the ACRS, which represents the system of the FK5. The data from the Algiers Zone, whose plates are centered between declinations -2 and +4 degrees (eq. 1900), have been analyzed for scale, rotation, tilt, coma, magnitude equation, radial distortion and distortions introduced by the use of reseaux in the Carte du Ciel program. The result is a positional catalog of over 199,000 stars on eq. J2000.0, epoch of observation. The plate were exposed between 1891 and 1912. For cross-identification purposes, all stars have been matched with the Tycho Input Catalog (revised); those numbers have been added to each record.
- ID:
- ivo://svo.cab/alhambra
- Title:
- ALHAMBRA Final Catalogue
- Short Name:
- ALHAMBRA
- Date:
- 03 Jun 2020 15:33:39
- Publisher:
- SVO CAB
- Description:
- This data server provides access to the ALHAMBRA Final Catalogue. The ALHAMBRA (Advance Large Homogeneous Area Medium Band Redshift Astronomical) survey (Moles et al. 2008) has observed 8 different regions of the sky, including sections of the COSMOS, DEEP2, ELAIS, GOODS-N, SDSS and Groth fields using a new photometric system with 20 contiguous, non-overlapping, equal width (~ 300A) filters, covering the optical range (3500A-9700A), plus the standard broadband NIR J, H and Ks filters. The observations were carried out with the Calar Alto (CAHA) 3.5m telescope using the wide field, 0.25 deg2 FOV optical camera LAICA and the NIR instrument Omega-2000. The ALHAMBRA survey dataset represents a ~700hrs of total exposure time, gathered in between the 2005 and 2012.Further information on the project can be found at the ALHAMBRA web page.
- ID:
- ivo://CDS.VizieR/J/MNRAS/463/4210
- Title:
- All-sky catalog of solar-type dwarfs
- Short Name:
- J/MNRAS/463/4210
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Most future surveys designed to discover transiting exoplanets, including TESS and PLATO, will target bright (V<13) and nearby solar-type stars having a spectral type later than F5. In order to enhance the probability of identifying transits, these surveys must cover a very large area on the sky, because of the intrinsically low areal density of bright targets. Unfortunately, no existing catalog of stellar parameters is both deep and wide enough to provide a homogeneous input list. As the first Gaia data release exploitable for this purpose is expected to be released not earlier than late 2017, we have devised an improved reduced-proper-motion method to discriminate late field dwarfs and giants by combining UCAC4 proper motions with APASS DR6 photometry, and relying on RAVEDR4 as an external calibrator. The output, named UCAC4-RPM, is a publicly-available, complete all-sky catalog of solar-type dwarfs down to V<13.5, plus an extension to logg>3.0 subgiants. The relatively low amount of contamination (defined as the fraction of false positives; <30%) also makes UCAC4-RPM a useful tool for the past and ongoing ground-based transit surveys, which need to discard candidate signals originating from early-type or giant stars. As an application, we show how UCAC4-RPM may support the preparation of the TESS (that will map almost the entire sky) input catalog and the input catalog of PLATO, planned to survey more than half of the whole sky with exquisite photometric precision.
- ID:
- ivo://CDS.VizieR/I/280B
- Title:
- All-Sky Compiled Catalogue of 2.5 million stars
- Short Name:
- I/280B
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The All-Sky Compiled Catalogue of 2501313 stars (ASCC-2.5) with the limiting magnitude V=12-14 is a result of a merging of star lists from present day large high-precision catalogues from space (Hipparcos- Tycho family catalogues: Hipparcos main catalogue including Multiple System Annex [I/239], Tycho-1 [I/239], Tycho-2 [I/259], ACT-RC [I/246], TRC [I/250]) and ground-based (PPM-N [I/146], PPM-S [I/193], PPM-add [I/208], CMC11 [I/256]) observations and reduction to standard systems of corresponding stellar data. The data from the Tycho-2 Spectral Type Catalog [III/231], and the 2MASS All-Sky Catalog of Point Sources [II/246] are added. The basic stellar data presented in the ASCC-2.5 are the equatorial coordinates (J2000, epoch 1991.25), proper motions in the Hipparcos system, B and/or V stellar magnitudes in the Johnson system. Additionally, for some stars we give trigonometric parallaxes, spectral classes in the MK or HD system, multiplicity and variability flags, Hipparcos, Tycho-2, HD, DM designations. Equatorial coordinates and their standard errors were taken from the source catalogues in accordance with the priority: Hipparcos [I/239/hip_main], Tycho-2 [I/259], Tycho-1 [I/239/tyc_main], CMC11 [I/256], PPM [I/146,I/193,I/208]. Proper motions from the source catalogues were compared with Hipparcos data.The compiled proper motions in the Hipparcos system and their standard errors were computed as the weighted means. The weights were set in accordance with the proper motion errors listed for individual stars in the source catalogues. Trigonometric parallaxes are taken from the Hipparcos and Tycho-1 catalogues. Stellar B, V magnitudes were determined on the basis of the ground- based photometric data taken from CMC11, Hipparcos, as well as space BT, VT from Tycho-1, Tycho-2. Magnitudes from the PPM catalogue were used if no other photometric data were available. Tycho data were transformed to the Johnson system via: V = VT - 0.09 (B-V)T + dV, (B-V) = 0.850 (B-V)T + d(B-V), i.e. using the recommendations from the Introduction to the Tycho catalogue and including additional corrections dV and d(B-V). These additional corrections were determined by comparison with ground-based data in the Johnson system. These corrections depend non-linearly on colour and reach 0.02 and 0.04 mag, respectively. Infrared stellar magnitudes J, H, K_s_ and their errors were copied from the 2MASS catalogue. Spectral classes in the MK or HD systems were taken from Hipparcos, CMC11, PPM, and Tycho-2 Spectral Type catalogues. Multiplicity and variability flags were taken from Tycho-1, Tycho-2, Hipparcos, CMC11, and PPM catalogues. The 1st version of the ASCC-2.5 contained some errors in the zones -1 to +1 degree which have been corrected (see details in the "History" section below). The 2nd version included a new file (ccadd.dat) containing the previously missing stars (including components of multiple systems). Note that the ASCC numbers did not change between the two versions, but additional numbers (2600001 to 2603318) were assigned. In the present 3rd version of the ASCC-2.5 the stars from file ccadd.dat are inserted in the basic files in accordance with their coordinates. Stars in the ASCC-2.5 are divided into 30 files ordered by declination (North and South polar caps and 28 bands of 5 degrees width), then sorted in order of right ascension within each file.
- ID:
- ivo://CDS.VizieR/J/A+A/437/1147
- Title:
- Amalthea and Thebe CCD astrometric obs.
- Short Name:
- J/A+A/437/1147
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents the results of observations of Jupiter's satellites Amalthea and Thebe made in 1995, 1996 and 2001 at the Laboratorio Nacional de Astrofisica (LNA), Brazil. The observations were made in visible light wavelengths with a 1.6m reflector telescope and the light of Jupiter was covered by a mask placed near the CCD surface. The already published positions for 1995, whose astrometric reduction used the Galilean satellites, are now reduced using the stars in the CCD fields like the new positions of 1996 and 2001. The 2001 data are much better than those obtained in 1995, and that those from 1996 show large residuals. Considering the 310 frames observed, the mean residual is about 0.01" and the standard deviation is about 0.15".
- ID:
- ivo://CDS.VizieR/V/67
- Title:
- An astrometric catalogue of radio stars
- Short Name:
- V/67
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Astrometric data in the optical and radio spectral ranges have been assembled for some 200 radio stars which are considered promising objects for linkage of optical and radio frames. Astrophysical data have been added to support observational programmes and data analysis. The full catalogue, in its original form as the file "catalog.ori", contains explanations, followed by the data for each star organised as paragraphs (blocks of lines separated by a blank line). Each paragraph representing a radio star in this catalog consists of 17 categories of stellar parameters; each category may contain zero, one, or more records. The positions, proper motions and parallaxes in the optical and radio domains are assigned categories 1 to 7; categories 8 to 13 deal with photometrical and spectroscopical parameters, duplicity and variability descriptions; and categories 14 to 17 contain references to finding charts and radio maps, as well as remarks about observation priorities. A detailed description of these categories are present at the beginning of the "catalog.ori" file.
- ID:
- ivo://CDS.VizieR/J/ApJS/125/409
- Title:
- Arcsecond positions of UGC galaxies
- Short Name:
- J/ApJS/125/409
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present accurate B1950 and J2000 positions for all confirmed galaxies in the Uppsala General Catalog (UGC, Cat. <VII/26>). The positions were measured visually from Digitized Sky Survey images with rms uncertainties {sigma}<=[(1.2")^2^+({theta}/100)^2^]^1/2^, where is the major-axis diameter. We compared each galaxy measured with the original UGC description to ensure high reliability. The full position list is available in the electronic version only. the major-axis diameter. We compared each galaxy measured with the original UGC description to ensure high reliability. The full position list is available in the electronic version only.
- ID:
- ivo://org.gavo.dc/arigfh/q/cone
- Title:
- ARIGFH identified objects
- Short Name:
- arigfh scs
- Date:
- 27 Dec 2024 08:31:12
- Publisher:
- The GAVO DC team
- Description:
- ARI's "Geschichte des Fixsternhimmels" is an attempt to collect all astrometrically useful observations from before ca. 1970 in a way comparable to what has been done to construct the FK* series of fundamental catalogs. About 7e6 published positions are included. In GAVO's DC, we provide tables of identified and non-identified stars together with the master catalog that objects were identified against.
- ID:
- ivo://org.gavo.dc/arihip/q/cone
- Title:
- ARIHIP astrometric catalogue
- Short Name:
- arihip cone
- Date:
- 27 Dec 2024 08:31:05
- Publisher:
- The GAVO DC team
- Description:
- The catalogue ARIHIP has been constructed by selecting the 'best data' for a given star from combinations of HIPPARCOS data with Boss' GC and/or the Tycho-2 catalogue as well as the FK6. It provides 'best data' for 90 842 stars with a typical mean error of 0.89 mas/year (about a factor of 1.3 better than Hipparcos for this sample of stars).