- ID:
- ivo://nasa.heasarc/aavsovsx
- Title:
- AAVSO International Variable Star Index
- Short Name:
- AAVSOVSX
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table contains Galactic stars known or suspected to be variable. It lists all stars that have an entry in the American Association of Variable Star Observers' (AAVSO) International Variable Star Index (VSX; <a href="http://www.aavso.org/vsx">http://www.aavso.org/vsx</a>). It consisted initially of the General Catalogue of Variable Stars (GCVS) and the New Catalogue of Suspected Variables (NSV) and was then supplemented with a large number of variable star catalogues, as well as individual variable star discoveries or variables found in the literature. Effort has also been invested to update the entries with the latest information regarding position, type and period and to remove duplicates. The VSX database is being continually updated and maintained. For historical reasons some objects outside of the Galaxy have been included. This table was created by the HEASARC based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/B/vsx">CDS catalog B/vsx</a>. The CDS updates it regularly, and this HEASARC version is accordingly updated within a week of such updates. This is a service provided by NASA HEASARC .
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- ID:
- ivo://nasa.heasarc/asiagosn
- Title:
- Asiago Supernova Catalog (Dynamic Version)
- Short Name:
- ASIAGOSN
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the dynamic version of the Asiago Supernova Catalog. It supersedes the original 1999 version by Barbon et al. (1999A&AS..139..531B, Cat. II/227), and contains data about the supernovae observed since 1885 and their parent galaxies through a few days prior to the most recent update. In addition to the list of newly discovered SNe, the literature has been searched for new information on past SNe as well. The data for the parent galaxies have also been homogenized. This table was created by the HEASARC based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/B/sn">CDS Catalog B/sn</a>. The CDS updates it regularly, and this HEASARC version is accordingly updated within a week of such updates. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/bnmdspecat
- Title:
- Brightest M Dwarfs in the Northern Sky Spectroscopic Catalog
- Short Name:
- BNMDSPECAT
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a spectroscopic catalog of the 1564 brightest (J < 9<sup>m</sup>) M-dwarf candidates in the northern sky, as selected from the SUPERBLINK proper-motion catalog (Lepine and Shara 2005, AJ, 129, 1483). Observations confirm 1408 of the candidates to be late-K and M dwarfs with spectral subtypes K7 - M6. From the low (mu > 40 mas yr<sup>-1</sup>) proper motion limit and high level of completeness of the SUPERBLINK catalog in that magnitude range, the authors estimate that their spectroscopic census most likely includes > 90% of all existing, northern-sky M dwarfs with apparent magnitude J < 9<sup>m</sup>. Only 682 stars in this sample are listed in the Third Catalog of Nearby Stars (CNS3, Gliese and Jahreiss 1991); most others are relative unknowns and have spectroscopic data presented here for the first time. Spectral subtypes are assigned based on spectral index measurements of CaH and TiO molecular bands; a comparison of spectra from the same stars obtained at different observatories, however, reveals that spectral band index measurements are dependent on spectral resolution, spectrophotometric calibration, and other instrumental factors. As a result, the authors find that a consistent classification scheme requires that spectral indices be calibrated and corrected for each observatory/instrument used. After systematic corrections and a recalibration of the subtype-index relationships for the CaH2, CaH3, TiO5, and TiO6 spectral indices, the authors find that they can consistently and reliably classify all the stars to a half-subtype precision. The use of corrected spectral indices further requires them to recalibrate the zeta parameter, a metallicity indicator based on the ratio of TiO and CaH optical bandheads. However, the authors find that their zeta values are not sensitive enough to diagnose metallicity variations in dwarfs of subtypes M2 and earlier (+/- 0.5 dex accuracy) and are only marginally useful at later M3-M5 subtypes (+/- 0.2 dex accuracy). Fits of their spectra to the Phoenix atmospheric model grid are used to estimate effective temperatures. These suggest the existence of a plateau in the M1-M3 subtype range, in agreement with model fits of infrared spectra but at odds with photometric determinations of T<sub>eff</sub>. Existing geometric parallax measurements are extracted from the literature for 624 stars, and are used to determine spectroscopic and photometric distances for all the other stars. Active dwarfs are identified from measurements of H-alpha equivalent widths, and the authors find a strong correlation between H-alpha emission in M dwarfs and detected X-ray emission from ROSAT and/or a large UV excess in the GALEX point source catalog. Proper motion data and photometric distances are combined in order to evaluate the (U, V, W) distribution in velocity space, which is found to correlate tightly with the velocity distribution of G dwarfs in the solar neighborhood. However, active stars show a smaller dispersion in their space velocities, which is consistent with those stars being younger on average. The authors state that this catalog will be very useful for guiding the selection of the best M dwarf targets for exoplanet searches, in particular those using high-precision radial velocity measurements. This online catalog was created by the HEASARC in June 2013 based on a machine-readable version of Tables 1, 3 and 7 from the paper which were obtained from the AJ website (Tables 1 and 3) or from the first author (Table 7). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/mdwarfasc
- Title:
- Bright M Dwarf All-Sky Catalog
- Short Name:
- MDWARFASC
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains an all-sky catalog of M dwarf stars with apparent infrared magnitude J < 10. The 8889 stars are selected from the ongoing SUPERBLINK survey of stars with proper motion mu > 40 mas yr<sup>-1</sup>, supplemented on the bright end with the Tycho-2 catalog. Completeness tests which account for kinematic (proper motion) bias suggest that this catalog represents ~75% of the estimated ~11,900 M dwarfs with J < 10 expected to populate the entire sky. The catalog is, however, significantly more complete for the northern sky (~90%) than it is for the south (~60%). Stars are identified as cool, red M dwarfs from a combination of optical and infrared color cuts, and are distinguished from background M giants and highly reddened stars using either existing parallax measurements or, if such measurements are lacking, using their location in an optical-to-infrared reduced proper motion diagram. These bright M dwarfs are all prime targets for exoplanet surveys using the Doppler radial velocity or transit methods; the combination of low-mass and bright apparent magnitude should make possible the detection of Earth-size planets on short-period orbits using currently available techniques. Parallax measurements, when available, and photometric distance estimates are provided for all stars, and these place most systems within 60 pc of the Sun. Spectral type estimated from V-J color shows that most of the stars range from K7 to M4, with only a few late M dwarfs, all within 20 pc. Proximity to the Sun also makes these stars good targets for high-resolution exoplanet imaging searches, especially if younger objects can be identified on the basis of X-ray or UV excess. For that purpose, we include X-ray flux from ROSAT and FUV/NUV ultraviolet magnitudes from GALEX for all stars for which a counterpart can be identified in those catalogs. Additional photometric data include optical magnitudes from Digitized Sky Survey plates and infrared magnitudes from the Two Micron All Sky Survey. This table was first created by the HEASARC in October 2011 based on electronic versions of Tables 1 and 2 from the reference paper which were obtained from the AJ web site. A slightly revised version based on corrected versions of the input tables received from the author was ingested in December 2011. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cocd
- Title:
- COCD: Catalog of Open Cluster Data
- Short Name:
- COCD
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Catalog of Open Cluster Data (COCD) is a result of studies of the wide neighborhoods of 513 open clusters and 7 compact associations carried out in the high-precision homogeneous All-Sky Compiled Catalog of 2.5 Million Stars (ASCC-2.5, Kharchenko 2001, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/I/280">CDS Cat. <I/280></a>). On the basis of data on about 33,000 possible members (including about 10,000 most probable ones) and homogeneous methods of cluster parameter determination, the angular sizes of cluster cores and coronae, cluster heliocentric distances, mean proper motions, mean radial velocities and ages were established and collected in the COCD. These include cluster distances for 200 clusters, average cluster radial velocities for 94 clusters, and cluster ages for 195 clusters derived for the first time. Clusters in the catalogue are sequenced in their Right Ascension J2000 order. The Open Cluster Diagrams Atlas (OCDA) presents a set of open cluster diagrams used for the determination of parameters of the 513 open clusters and 7 compact associations, and is intended to illustrate the quality of the constructed cluster membership (Kharchenko et al. 2004, CDS Cat. <J/AN/325/740>), and the accuracy of the derived cluster parameters. Every diagram presents relation between various stellar data from the ASCC-2.5 in the area of the specific cluster. There are five diagrams provided for every cluster in the Atlas: the area map, the density profile, the vector point diagram, the magnitude equation diagram and the color-magnitude diagram. The OCDA PostScript plots (one file per cluster) are available as a remote data product for entries in this table. This table was created by the HEASARC in May 2011 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/438/1163">CDS Catalog J/A+A/438/1163</a> files cocd.dat and notes.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cocdext1
- Title:
- COCD: Catalog of Open Cluster Data First Extension
- Short Name:
- COCDEXT1
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a list of 130 Galactic open clusters, found in the All-Sky Compiled Catalogue of 2.5 Million Stars (ASCC-2.5) and not included in the original Catalog of Open Cluster Data (COCD): it is known as the 1st Extension of the COCD (COCD-1). For these new clusters, the authors determined a homogeneous set of astrophysical parameters such as size, membership, motion, distance and age. In their previous work (the Browse table COCD based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/438/1163">CDS Cat. J/A+A/438/1163</a>), 520 already-known open clusters out of a sample of 1700 clusters from the literature were confirmed in the ASCC-2.5 using independent, objective methods. Using these same methods, the whole sky was systematically screened for new clusters. The newly detected clusters show the same distribution over the sky as the known ones. It is found that without the a priori knowledge about existing clusters the authors' search lead to clusters which are, on average, brighter, have more members and cover larger angular radii than the 520 previously-known ones. On the basis of data on about 6,200 possible members (including about 2,200 most probable ones) and homogeneous methods of cluster parameter determination, the angular sizes of cluster cores and coronae, cluster heliocentric distances, colour-excesses, mean proper motions, and ages of 130 clusters and mean radial velocities of 69 clusters were established and collected in the COCD-1. Clusters in the catalogue are numbered in order of increasing J2000.0 Right Ascension. The 1st Extension of the Open Cluster Diagrams Atlas (OCDA-1) presents a set of open cluster diagrams used for the determination of parameters of the 130 newly discovered open clusters, and is intended to illustrate the quality of the constructed cluster membership, and the accuracy of the derived cluster parameters. Every diagram presents relations between various stellar data from the all sky catalog ASCC-2.5(Kharchenko, 2001, CDS Cat. <I/280>) in the area of the specific cluster. There are five diagrams provided for every cluster in the Atlas: the area map, the density profile, the vector point diagram, the "magnitude equation" (proper motion in each coordinate versus V magnitude) diagram, and the color-magnitude diagram. The 130 OCDA-1 PostScript plots (one file per cluster) are available as a remote data product for all of the entries in this table. This table was created by the HEASARC in May 2011 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/440/403/">CDS Catalog J/A+A/440/403/</a> files cluster.dat and notes.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/goscat
- Title:
- Galactic O Stars with Accurate Spectral Classes Catalog
- Short Name:
- GOSCAT
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The authors have produced a catalog of 378 Galactic O stars (the GOS Catalog) with accurate spectral classifications that is complete for V < 8 but includes many fainter stars. The catalog provides cross-identifications with other sources; coordinates (obtained in most cases from Tycho-2 data); astrometric distances for 24 of the nearest stars; optical (Tycho-2, Johnson, and Stroemgren) and NIR photometry; group membership, runaway character, and multiplicity information. There is also a web-based version of this catalog with links to online services at <a href="http://www-int.stsci.edu/~jmaiz/research/GOS/GOSmain.html">http://www-int.stsci.edu/~jmaiz/research/GOS/GOSmain.html</a> This table was created by the HEASARC in February 2009 based on the electronic versions of Tables 1, 2, 5, 6, 8, 9, 10, 11, 12 and 13 obtained from the CDS, namely their catalog V/116 (files main.dat, posplx.dat, tyc2mmag.dat, ubvmag.dat and dist.dat). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/lmcextobj
- Title:
- Large Magellanic Cloud Extended Objects Catalog
- Short Name:
- LMCEXTOBJ
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- A survey of extended objects in the Large Magellanic Cloud (LMC) was carried out on the ESO/SERC R and J Sky Survey Atlases, checking entries in previous catalogs and searching for new objects. The census provided 6659 objects including star clusters, emission-free associations, and objects related to emission nebulae. Each of these classes contains three subclasses with intermediate properties, which are used to infer total populations. The survey includes cross-identifications among catalogs, and includes 3246 new objects (~49% of the unified catalog). The authors have provided accurate positions, classification, and homogeneous measurements of sizes and position angles, as well as information on cluster pairs and hierarchical relation for superimposed objects. This unification and enlargement of catalogs is important for future searches of fainter and smaller new objects. The present catalog together with its previous counterpart for the SMC and the inter-Cloud region provide a total population of 7847 extended objects in the Magellanic System. The angular distribution of the ensemble reveals important clues on the interaction between the LMC and SMC. This table was created by the HEASARC in March 2007 based on the CDS table J/AJ/117/238, file table2.dat and contains the 6659 extended objects found in this LMC survey. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/oriysoir
- Title:
- Orion Nebula YSO IR Properties
- Short Name:
- ORIYSOIR
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The origin and evolution of the X-ray emission in very young stellar objects (YSOs) are not yet well understood because it is very hard to observe YSOs in the protostellar phase. Using COUP data, the authors studied in their reference paper the X-ray properties of stars in the Orion Nebula Cluster (ONC) in different evolutionary classes: luminosities, hydrogen column densities N<sub>H</sub>, effective plasma temperatures, and time variability were compared to understand if the interaction between the circumstellar material and the central object can influence the X-ray emission. They have assembled the deepest and most complete photometric catalog of objects in the ONC region from the UV to 8 microns (µm) using data from the HST Treasury Program; deep and almost simultaneous UBVI and JHK images taken, respectively, with WFI at ESO 2.2m and ISPI at CTIO 4m telescopes; and Spitzer IRAC imaging. They selected high-probability candidate Class 0-I protostars, a sample of "bona fide" Class II stars, and a set of Class III stars with IR emission consistent with normal photospheres. Their principal result is that Class 0-Ia objects are significantly less luminous in X-rays, in both the total and hard bands, than the more evolved Class II stars with mass larger than 0.5M_{sun}_; the latter show X-ray luminosities similar to those of Class 0-Ib stars. This table contains the JHK and IRAC data, as well as the protostar classifications, for 398 ONC YSOs. This online catalog was created by the HEASARC in October 2010 based on the machine-readable versions of Tables 2, 3, 4 and 5 from the reference paper which were obtained from the CDS (their catalog J/ApJ/677/401). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/pg
- Title:
- Palomar-Green Catalog of UV-Excess Stellar Objects
- Short Name:
- PG
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Palomar-Green Catalog of UV-Excess Stellar Objects provides positions (the original_ra and original_dec parameters) accurate to about 8 arcsec in each coordinate, photographic B-magnitudes accurate to 0.29 mag, spectral types, some cross-references, and photoelectric broad-band, multichannel, and Stroemgren colors when available. Of the 1874 objects in the catalog as published in 1986 (1878 in this version), 1715 comprise a statistically complete sample covering 10714 square degrees from 266 fields taken on the Palomar 18-inch Schmidt telescope. Limiting magnitudes vary from field to field, ranging from 15.49 to 16.67. The overall completeness is estimated to be 84%, but that figure and the relative contributions of magnitude, color, and accidental errors vary depending on the magnitude and color distribution of the spectroscopic subsample. The dominant population in this catalog is that of the hot, hydrogen-atmosphere subdwarfs, the sdB stars, which comprise nearly 40 per cent of the sample. The hot white dwarfs of spectral types DA, DB, and DO account for 21, 2.8, and 1.0 per cent of the sample, respectively, while cooler DC or DZ white dwarfs add another 1.2 per cent. Cataclysmic variables and composite-spectrum binaries account for 5 per cent, although many other spectra dominated by a hot star showed evidence for a cool companion at red wavelengths. Planetary nebulae central stars account for another 0.5 per cent. Extragalactic objects comprise about 9 per cent of the complete sample, with QSOs representing 5.4 per cent. Only 0.3 per cent (6 objects) remain with totally unsatisfactory or unknown spectral classes. (Notice that all of these percentage estimates are based on the published version of this catalog, and that the values in the current online version may be slightly different, as the latter includes a small number of updates and additions). In 2009, an additional data resource was added to this catalog by CDS, namely a file containing more accurate (sub-arcsecond) positions and V magnitudes (the skiff_vmag parameter), and also additional comments (the skiff_comments parameter). This new material has now been included in the HEASARC version of the PG Catalog. A full discussion of this addition can be found at <a href="http://cdsarc.u-strasbg.fr/ftp/cats/II/207A/pg_2009.txt">http://cdsarc.u-strasbg.fr/ftp/cats/II/207A/pg_2009.txt</a>. This database was initially made available at the HEASARC in June 1998 based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/II/207A">CDS catalog II/207A</a> file catalog.dat which had been last updated on Oct 17 1997. In 2017, the HEASARC re-ingested this CDS catalog as it had been updated several times in the interim, notably in 2009 when an additional file (pg_pos.dat) with precise coordinates and comments provided by Brian Skiff was added. This is a service provided by NASA HEASARC .
