- ID:
- ivo://nasa.heasarc/sbsggencat
- Title:
- Second Byurakan Survey General Catalog Galaxies Optical Database
- Short Name:
- SBSGGENCAT
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Second Byurakan Survey (SBS) is a continuation of the First Byurakan Survey (FBS), also known as the Markarian Survey. The goal of the SBS was to reach fainter objects (as faint as limiting photographic magnitudes of 19.5, about 2.5 magnitudes fainter than the Markarian survey) and discover new active and star-forming galaxies using both UV excess and emission-line techniques. In this table, a database for the entire catalog of the Second Byurakan Survey (SBS) galaxies is presented, i.e, the 1700 SBS stars listed in Stepanian (2005) are not included herein. It contains new measurements of their optical parameters and additional information taken from the literature and other databases. The measurements were made using I<sub>pg</sub> (near-infrared), F<sub>pg</sub> (red) and J<sub>pg</sub> (blue) band images from photographic sky survey plates obtained by the Palomar Schmidt telescope and extracted from the STScI Digital Sky Survey (DSS). The database provides accurate coordinates, morphological type, spectral and activity classes, apparent magnitudes and diameters, axial ratios, and position angles, as well as number counts of neighboring objects in circles of radii 50 kpc around the sources. The total number of individual SBS objects in the database is now 1676. The 188 Markarian galaxies which were re-discovered by the SBS are not included in this database. the authors also include redshifts that are now available for 1576 SBS objects, as well as 2MASS infrared magnitudes for 1117 SBS galaxies. The new optical information on the SBS galaxies was obtained from images extracted from the STScI Digitized Sky Survey (DSS) of F_pg (red), J_pg (blue) and I_pg (near-infared) band photographic sky survey plates obtained by the Palomar telescope. This table was created by the HEASARC in May 2012 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/VII/264">CDS Catalog J/VII/264</a> file sbs.dat. This is a service provided by NASA HEASARC .
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- ID:
- ivo://nasa.heasarc/fermifhl
- Title:
- Second Catalog of Hard Fermi-LAT Sources (2FHL)
- Short Name:
- FERMIFHL
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This is a catalog of sources detected above 50 GeV by the Fermi-Large Area Telescope (LAT) in 80 months of data. The newly delivered Pass 8 event-level analysis allows the detection and characterization of sources in the 50GeV-2TeV energy range. In this energy band, Fermi-LAT has detected 360 sources, which constitute the second catalog of hard Fermi-LAT sources (2FHL). The improved angular resolution enables the precise localization of point sources (~1.7-arcminutes radius at 68% confidence level) and the detection and characterization of spatially extended sources. The authors found that 86% of the sources could be associated with counterparts at other wavelengths, of which the majority (75%) are active galactic nuclei and the rest (11%) are Galactic sources. Only 25% of the 2FHL sources have been previously detected by Cherenkov telescopes, implying that the 2FHL provides a reservoir of candidates to be followed up at very high energies. This work closes the energy gap between the observations performed at GeV energies by Fermi-LAT on orbit and the observations performed at higher energies by Cherenkov telescopes from the ground. This database table was first ingested by the HEASARC in September 2015 using electronic data obtained from the Fermi Science Support Center (FSSC). That data is available at <a href="http://fermi.gsfc.nasa.gov/ssc/data/access/lat/2FHL/">http://fermi.gsfc.nasa.gov/ssc/data/access/lat/2FHL/</a>. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/intagncat
- Title:
- Second INTEGRAL AGN Catalog
- Short Name:
- INTAGNCAT
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The INTEGRAL mission provides a large data set for studying the hard X-ray properties of AGN and allows testing the unified scheme for AGN. This table contains some of the results from the analysis of INTEGRAL IBIS/ISGRI, JEM-X, and OMC data for 199 AGN (and 3 clusters of galaxies) that have been reported to be detected by INTEGRAL at energies above 20 keV. The data analyzed therein allowed a significant spectral extraction on 148 objects and optical variability study of 57 AGN. The slopes of the hard X-ray spectra of Seyfert 1 and Seyfert 2 galaxies were found to be consistent within the uncertainties, whereas lower luminosities were measured for the more absorbed/type 2 AGN. The intermediate Seyfert 1.5 objects exhibit hard X-ray spectra consistent with those of Seyfert 1 galaxies. When applying a Compton reflection model, the underlying continua appear still the same in Seyfert 1 and 2 with photon index 2, and the reflection strength is about R = 1, when assuming different inclination angles. A significant correlation is found between the hard X-ray and optical luminosity and the mass of the central black hole, in the sense that the more luminous objects appear to be more massive. There is also a general trend for the absorbed sources and type 2 AGN to have lower Eddington ratios. The black hole mass appears to form a fundamental plane together with the optical and X-ray luminosity of the form L<sub>V</sub> being proportional to L<sub>X</sub><sup>0.6</sup> M<sub>BH</sub><sup>0.2</sup>, similar to that found between radio luminosity L<sub>R</sub>, L<sub>X</sub>, and M<sub>BH</sub>. The unified model for Seyfert galaxies seems to hold, showing in hard X-rays that the central engine is the same in Seyfert 1 and 2 but seen under different inclination angles and absorption. A catalog of 199 IBIS/ISGRI detected AGN is presented. For those 148 objects significantly detected in the data set analyzed here, spectral parameters, fluxes, and luminosities are given. In addition, the photometric table of OMC measurements in the V-band (given for 57 of the AGN) is also included herein. For objects with more complex spectra, notice, the results of a fit to a cut-off power law model were presented in Table 3 of the reference paper, but are not included in this HEASARC table. The JEM-X spectra of the 23 AGN detected by the X-ray monitor were fit with the IBIS/ISGRI data, and the results of this were presented in Table 4 of the reference paper, but are also not included in this HEASARC table. This table was created by the HEASARC in November 2009 based on the electronic version of Tables 1, 2 and 5 from the reference paper which was obtained from the CDS (their catalog J/A+A/505/417 files table1.dat, table2.dat and table5.dat). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rass2rxs
- Title:
- Second ROSAT All-Sky Survey Point Source Catalog (2RXS)
- Short Name:
- RASS2RXS
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table contains the Second ROSAT All-Sky Survey Point Source Catalog (2RXS). This is the second publicly released ROSAT catalog of point-like sources obtained from the ROSAT All-Sky Survey (RASS) observations performed with the Position-Sensitive Proportional Counter (PSPC) between June 1990 and August 1991. It is an extended, revised, and combined version of the RASS <a href="/W3Browse/rosat/rassbsc.html">Bright</a> and <a href="/W3Browse/rosat/rassfsc.html">Faint Source Catalog</a>s. Utilizing the latest RASS processing, this catalog includes more than 135,000 X-ray detections in the 0.1-2.4 keV energy band down to a likelihood threshold of 6.5. Additional information can be found at <a href="http://www.mpe.mpg.de/ROSAT/2RXS/">http://www.mpe.mpg.de/ROSAT/2RXS/</a>. This table was created by the HEASARC in March, 2017, based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/588/A103">CDS Catalog J/A+A/588/A103</a> file cat2rxs.dat.gz. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/sa57xmm
- Title:
- Selected Area 57 XMM-Newton X-Ray Source Catalog
- Short Name:
- SA57XMM
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The maximum number density of Active Galactic Nuclei (AGNs), as deduced from X-ray studies, occurs at z >= 1, with lower luminosity objects peaking at smaller redshifts. Optical studies lead to a different evolutionary behaviour, with a number density peaking at z ~ 2 independently of the intrinsic luminosity, but this result is limited to active nuclei brighter than the host galaxy. A selection based on optical variability can detect low luminosity AGNs (LLAGNs), where the host galaxy light prevents the identification by non-stellar colours. The authors collected X-ray data in a field where there existed an optically-selected sample of "variable galaxies", i.e. variable objects with diffuse appearance, in order to investigate the X-ray and optical properties of the population of AGNs, particularly of low luminosity ones, where the host galaxy is visible. They observed a field of ~ 0.2 deg<sup>2</sup> in the Selected Area 57, for 67 ks with XMM-Newton. They correlated the list of detected X-ray sources with a photographic survey of SA 57, complete to B_J ~ 23 and with the available spectroscopic data. They obtained a catalog of 140 X-ray sources to limiting fluxes of 5 x 10<sup>-16</sup> and 2 x 10<sup>-15</sup> erg/cm<sup>2</sup>/s in the 0.5 - 2 keV and 2 - 10 keV bands, respectively, 98 of which are identified in the optical bands. The X-ray detection of part of the variability-selected candidates confirms their AGN nature. Diffuse variable objects populate the low luminosity side of the sample. Only 25/44 optically-selected QSOs are detected in X-rays. 15% of all QSOs in the field have X/O < 0.1. Additional information on the likely optical counterparts of 98 of the X-ray sources is available in the reference paper, e.g., in Table 3. This table was created by the HEASARC in September 2007 based on CDS table J/A+A/469/1211 file table2.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/selhcgcxo
- Title:
- Selected Hickson Compact Groups Chandra X-Ray Point Source Catalog
- Short Name:
- SELHCGCXO
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the Chandra X-ray point source catalogs for 9 Hickson Compact Groups (HCGs, 37 galaxies) at distances of 34 to 89 Mpc. The authors perform detailed X-ray point source detection and photometry and interpret the point source population by means of simulated hardness ratios. They thus estimate X-ray luminosities (L<sub>X</sub>) for all sources, most of which are too weak for reliable spectral fitting. For all sources, they provide counts, count rates, power-law indices (Gamma), hardness ratios, and L<sub>X</sub>, in the full (0.5-8.0 keV), soft (0.5-2.0 keV) and hard (2-8 keV) bands. In their paper, the authors use optical emission-line ratios from the literature to re-classify 24 galaxies as star-forming, accreting onto a supermassive black hole (AGNs), transition objects, or low-ionization nuclear emission regions. Two-thirds of their galaxies have nuclear X-ray sources with Swift/UVOT counterparts. Two nuclei have full-band X-ray luminosities >= 10<sup>42</sup> erg s<sup>-1</sup>, are strong multi-wavelength AGNs, and follow the known alpha<sub>OX</sub> - nu L_nu(near-UV)_ correlation for strong AGNs. Otherwise, most nuclei are X-ray faint, consistent with either a low-luminosity AGN or a nuclear X-ray binary population, and fall into the 'non-AGN' locus in alpha<sub>OX</sub> - nu L_nu(near-UV)_ space, which also hosts other normal galaxies. Each group was observed at the aim point of the back-illuminated S3 CCD of Chandra's Advanced CCD Imaging Spectrometer (ACIS), with the exception of HCG 90, which was observed with the ACIS-I array. The details of the 9 Chandra observations analyzed herein are given in Table 1 of the reference paper. The full details of the X-ray analysis and point source detection procedures are given in Section 3 of the reference paper. This table was created by the HEASARC in June 2014 based on electronic versions of Tables 2 and 3 from the reference paper which were obtained from the ApJS web site. Some of the values for the name parameter in the HEASARC's implementation of this table were corrected in April 2018. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/sgraregcsc
- Title:
- Sgr A* Region Compact Radio Source Catalog
- Short Name:
- SGRAREGCSC
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Recent broad-band 34- and 44-GHz radio continuum observations of the Galactic center have revealed 41 massive stars identified with near-IR (NIR) counterparts, as well as 44 proplyd candidates within 30 arcseconds of Sgr A*. Radio observations obtained in 2011 and 2014 have been used to derive proper motions of eight young stars near Sgr A*. The accuracy of proper motion estimates based on NIR observations by Lu et al. (2009, ApJ, 690, 1463) and Paumard et al. (2006, ApJ, 643, 1011) have been investigated by using their proper motions to predict the 2014 epoch positions of NIR stars and comparing the predicted positions with those of radio counterparts in the 2014 radio observations. Predicted positions from Lu et al. show an rms scatter of 6 milliarcseconds (mas) relative to the radio positions, while those from Paumard et al. show rms residuals of 20 mas. In the reference paper, the authors also determine the mass-loss rates of 11 radio stars, finding rates that are on average ~2 times smaller than those determined from model atmosphere calculations and NIR data. Clumpiness of ionized winds would reduce the mass loss rate of WR and O stars by additional factors of 3 and 10, respectively. One important implication of this is a reduction in the expected mass accretion rate onto Sgr A* from stellar winds by nearly an order of magnitude to a value of a few x 10<sup>-7</sup> solar masses per year. The authors carried out A-array observations of the Galactic center region (VLA program 14A-232) in the Ka (9 mm, 34.5 GHz) band on 2014 March 9 in which they detected 318 compact radio sources within 30" of Sgr A*. The authors searched for NIR counterparts to these compact radio sources using high-angular resolution AOs-assisted imaging observations acquired with the VLT/NACO. A K<sub>s</sub>-band (central wavelength 2.18 micron) image was obtained in a rectangular dither pattern on 2012 September 12. L'-band (3.8 micron) observations were obtained during various observing runs between 2012 June and September. The authors found that 45 of the compact radio sources had stellar counterparts in the K<sub>s</sub> and L' bands. This table contains the details of the 318 compact radio sources detected at 34.5 GHz and their NIR counterparts. This table was created by the HEASARC in November 2016 based on CDS table J/ApJ/809/10, file table6.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/shk
- Title:
- Shakbazian Compact Groups of Galaxies
- Short Name:
- Shk.(Group)
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This catalog is a compilation of ten lists of compact groups of compact galaxies found on the Palomar Sky Survey red charts and published in the period 1973 to 1979 by Shakhbazian, Petrosian, and collaborators. The catalog contains 377 groups of compact galaxies and includes identifications, equatorial coordinates, numbers of constituent galaxies, magnitudes of the brightest member, sizes of the groups as a whole, and coefficients of relative compactness. The HEASARC has a related database table, SHKGALAXY, which contains data on the individual galaxies in the Shakhbazian Compact Groups. This database table was created by the HEASARC in December, 1999, based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/89B">CDS catalog VII/89B</a>. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/shkgalaxy
- Title:
- Shakhabazian (Shk) Compact Groups of Galaxies: Individual Galaxies Data
- Short Name:
- Shk.(Gal.)
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The largest survey of compact galaxy groups was published by Shakhbazian et al. (the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/89">CDS catalog VII/89</a>, implemented by the HEASARC as the SHK database table). This present catalog provides accurate positions of the individual galaxies in the groups; photometric properties of the Southern sky (delta not greater than +2.5 degrees) are evaluated on the basis of the COSMOS/UKST catalog of the Southern sky. This catalog contains 373 groups; this number differs from the number in Shakhbazian's list (377 groups) by the following: (i) there are no data for groups 001 (already published by other authors), 206 and 241 (could not be re-identified), 252 (this is identical with 214), 301 and 353 (could not be re-identified); (ii) Group 328 was published twice (in North and South); and (iii) Group 340 was divided in two parts (340 and 340a), according to Bettoni and Fasano ([BF95]=1995AJ....109...32B). This HEASARC version of the catalog contains a total of 3435 individual galaxies identified as members of the compact groups, 2574 from the northern part of this survey (taken from the ADS Catalog VII/196 file north.dat), and 861 from the southern part of this survey (extracted from the 10746 entries in the ADS Catalog VII/196 file south.dat by including only entries corresponding to bona fide group members). This database table was created by the HEASARC in June, 2000, based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/196">CDS Catalog VII/196</a> (files north.dat and south.dat). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/hiiregion
- Title:
- Sharpless H II Regions
- Short Name:
- Sharpless
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table is derived from data contained in the Sharpless Catalogue of H II regions. The original catalog was published in 1959 in the Astrophysical Journal Supplement Series (number 41, pages 257- 280). The original card deck was in the 026 punch and this was converted to a 029 deck. Many of the quantities in this version of the catalog were not in the published catalog. The epochs of the precessed equatorial coordinates were determined empirically from the data as given on the computer cards. This is a service provided by NASA HEASARC .
