- ID:
- ivo://nasa.heasarc/gc47tuccx2
- Title:
- 47 Tuc Globular Cluster Chandra X-Ray Point Source Catalog (2017 Version)
- Short Name:
- GC47TUCCX2
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The authors combined Chandra ACIS observations of the globular cluster 47 Tucanae (47 Tuc) from 2000, 2002, and 2014-2015 to create a deeper X-ray source list and study some of the faint radio millisecond pulsars (MSPs) present in this cluster. This work combined 180 ks of new Chandra ACIS data on 47 Tuc with 370 ks of archival data and used improved algorithms to generate a new source catalog, finding 81 new sources for a total of 370 within the half-mass region (2.79 arcsec) of the cluster. The majority of the newly identified sources are in the crowded core region, indicating cluster membership. The authors associated five of the new X-ray sources with chromospherically active BY Dra or W UMa variables identified by Albrow et al. (2001, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/559/1060">CDS Cat. <J/ApJ/559/1060></a>). See also the related <a href="gc47tuccxo.html">2005 source catalog</a>. This table was created by the HEASARC in September 2020 based upon the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/472/3706">CDS Catalog J/MNRAS/472/3706</a> files table2.dat, table4.dat, and table5.dat. The optical names from Albrow et al. (2001) were subsequently corrected in October 2020 in order to use the recommendation from the CDS Dictionary of Nomenclature of Celestial Objects. This is a service provided by NASA HEASARC .
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- ID:
- ivo://nasa.heasarc/gc47tuccxo
- Title:
- 47 Tuc Globular Cluster Chandra X-Ray Point Source Catalog (2005 Version)
- Short Name:
- GC47TUCCXO
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The authors have detected 300 X-ray sources within the half-mass radius (2.79') of the globular cluster 47 Tucanae in a deep (281 ks) Chandra exposure. They perform photometry and simple spectral fitting for our detected sources and construct luminosity functions, X-ray color-magnitude, and color-color diagrams. Eighty-seven X-ray sources show variability on timescales from hours to years. Thirty-one of the new X-ray sources are identified with chromospherically active binaries from the catalogs of Albrow and coworkers (2001, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/559/1060">CDS Catalog <J/ApJ/559/1060></a>). The authors estimate that the total number of neutron stars in 47 Tuc is of order 300, reducing the discrepancy between theoretical neutron star retention rates and observed neutron star populations in globular clusters. The data used in this paper are from the 2000 and 2002 Chandra observations of the globular cluster 47 Tuc. The 2000 observations, initially described in Grindlay et al. (2001, Science 292, 2290), were performed with the ACIS-I CCD array at the telescope focus, while the 2002 observations placed the back-illuminated ACIS-S aim point at the focus for maximum low-energy sensitivity. The authors combined the results from wavdetect source detection runs with a threshold probability of 1 x 10<sup>-5</sup>, in two energy bands (0.5 - 2.0 keV and 0.5 - 6.0 keV for the 2000 observations, and (0.3 - 2.0 keV and 0.3 - 6.0 keV for the 2002 observations), to make independent source lists for the 2000 and 2002 observations, given in Tables 2 and 3 of the reference paper, which have been combined in the present HEASARC table. A total of 146 sources were detected in this way in the 2000 observations (entries with dataset_year = 2000), while 300 sources were detected in the 2002 observations (dataset_year = 2002). A total of 143 of the sources were clearly detected in both observations, while only three of the sources from the 2000 observations were not detected in the 2002 observations. See also the related <a href="gc47tuccx2.html">2017 source catalog</a>. This table was created by the HEASARC in June 2007 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/625/796">CDS Catalog J/ApJ/625/796</a> files table2.dat, table3.dat, and (part of) table5.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/tramisuboo
- Title:
- Two-Meter Radio Mini Survey (T-RaMiSu) of the Bootes Field
- Short Name:
- TRAMISUBOO
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains results from wide-area, deep, high-resolution 153-MHz GMRT observations of the NOAO Bootes field, adding to the extensive, multi-wavelength data of this region. The observations, data reduction, and catalog construction and description are described in the reference paper. The seven pointings (listed in Table 2 of the reference paper) produced a final mosaic covering 30 square degrees with a resolution of 25". The rms noise is 2 mJy/beam in the center of the image, rising to 4-5 mJy/beam at the edges, with an average of 3 mJy/beam. Seventy-five per cent of the area has an rms < 4 mJy/beam. The extracted source catalog contains 1289 sources detected at 5 sigma at flux densities between 4.1 mJy and 7.3 Jy, of which 453 are resolved. The authors estimate the catalogue to be 92% reliable and 95% complete at an integrated flux density limit of 14 mJy. The flux densities and astrometry have been corrected for systematic errors. In their paper, the authors calculate the differential source counts which are in good agreement with those in the literature and provide an important step forward in quantifying the source counts at these low frequencies and low flux densities. The GMRT 153-MHz sources have been matched to the 1.4-GHz NVSS and 327-MHz WENSS catalogs and spectral indices were derived. The source catalog presented here is derived from seven 4 hour pointings with the GMRT at 153 MHz, centered on the NOAO Bootes field. The resulting 30 square degree image has a central noise level of 2 mJy/beam and a resolution of 25". This table contains entries for all 1289 detected 153-MHz radio sources as well as for the 160 Gaussian components of the 77 sources (71 doubles and 3 triples) which could be fit by multiple Gaussian components, making a total of 1449 entries. This table was created by the HEASARC in January 2013 based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/549/A55">CDS Catalog J/A+A/549/A55</a> files table2.dat and table3.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/tycho2
- Title:
- Tycho-2 Catalog of the 2.5 Million Brightest Stars
- Short Name:
- Tycho-2
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Hipparcos and Tycho catalogs are the primary products of the European Space Agency's astrometric mission, Hipparcos. The satellite, which operated for four years, returned high quality scientific data from November 1989 to March 1993. The Tycho-2 catalog is an astrometric reference catalog containing positions and proper motions as well as two-color photometric data for the 2.5 million brightest stars in the sky. The Tycho-2 positions and magnitudes are based on precisely the same observations as the original Tycho catalog (hereafter Tycho-1; see <a href="https://cdsarc.cds.unistra.fr/ftp/cats/I/239">CDS Cat. I/239</a>) collected by the star mapper of the ESA Hipparcos satellite, but Tycho-2 is much bigger and slightly more precise, owing to a more advanced reduction technique. Components of double stars with separations down to 0.8 arcsec are included. Proper motions precise to about 2.5 mas/yr are given as derived from a comparison with the Astrographic Catalogue and 143 other ground-based astrometric catalogs, all reduced to the Hipparcos celestial coordinate system. Tycho-2 supersedes in most applications Tycho-1, as well as the ACT (<a href="https://cdsarc.cds.unistra.fr/ftp/cats/I/246">CDS Cat. I/246</a>) and the TRC (CDS Cat. I/250) catalogs based on Tycho-1. Supplement-1 (not part of this HEASARC database but available at <a href="https://cdsarc.cds.unistra.fr/ftp/cats/I/259/suppl_1.dat.gz">https://cdsarc.cds.unistra.fr/ftp/cats/I/259/suppl_1.dat.gz</a>) lists stars from the Hipparcos and Tycho-1 catalogs which are not in Tycho-2. Supplement-2 (not part of this HEASARC database but available at <a href="https://cdsarc.cds.unistra.fr/ftp/cats/I/259/suppl_2.dat.gz">https://cdsarc.cds.unistra.fr/ftp/cats/I/259/suppl_2.dat.gz</a>) lists 1146 Tycho-1 stars which are probably either false or heavily disturbed. The principal characteristics of the Tycho-2 catalog are summarized below. By means of proper motions the positions are transferred to the year 2000.0, the epoch of the catalog. The median values of internal standard errors are given: <pre> Mean satellite observation epoch ~J1991.5 Epoch of the Tycho-2 catalog J2000.0 Reference system ICRS coincidence with ICRS (1) +/-0.6 mas deviation from inertial (1) +/-0.25 mas/yr Number of entries 2,539,913 Astrometric standard errors (2) V_T < 9 mag 7 mas all stars, positions 60 mas all stars, proper motions 2.5 mas/yr Photometric std. errors (3) on V_T V_T < 9 mag 0.013 mag all stars 0.10 mag Star density b= 0 deg 150 stars/sq.deg. b= +/-30 deg 50 stars/sq.deg. b= +/-90 deg 25 stars/sq.deg. Completeness to 90 per cent V ~ 11.5 mag Completeness to 99 per cent V ~ 11.0 mag Number of Tycho observations ~300 10<sup>6</sup> Note (1): about all 3 axes Note (2): ratio of external to internal standard errors is ~1.0 for positions and for proper motions. Systematic errors are less than 1 mas and 0.5 mas/yr Note (3): ratio of photometric external to internal standard errors at V_T > 9 mag is below 1.5 </pre> For more information on the original catalog, please consult the Tycho-2 home page at <a href="http://www.astro.ku.dk/~erik/Tycho-2">http://www.astro.ku.dk/~erik/Tycho-2</a> For more information on the HEASARC implementation of the Tycho-2 catalog, please consult <a href="#heasarc_implementation">the "HEASARC Implementation" section</a> of this help. This database table was created at the HEASARC in June 2000 based on the ADC/<a href="https://cdsarc.cds.unistra.fr/ftp/cats/I/259">CDS Catalog I/259</a>, using the file tyc2.dat. Galactic coordinates (calculated by converting the observed ICRS Equatorial positions) were added to this HEASARC database table in August 2005. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/uhuru4
- Title:
- Uhuru Fourth (4U) Catalog
- Short Name:
- UHURU4
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Fourth Uhuru (4U) Catalog lists 339 X-ray sources that were observed with the Uhuru (SAS A) X-ray observatory. It contains positional information in the form of 90% confidence level error boxes, 2-6 keV intensities, possible optical and radio counterparts, and alternative names for sources observed in earlier compilations. The major classes of identified objects include binary stellar systems, supernova remnants, Seyfert galaxies, clusters of galaxies, and possibly the new class of superclusters of galaxies. The Uhuru satellite was a scanning X-ray instrument with a narrow (1 by 10 degree FWFM) and a wide (10 by 10 degree FWFM) collimator (cf. Giacconi et al. 1971, ApJ, 165, L27). Typically, the scan rate was 0.5 degree/second, with the spin axis in one position for roughly one day. During the interval for which the spin axis was fixed, repeated scans were made of the same 10 by 360 degrees band of the sky. For this catalog, the individual scans were superposed using aspect data from an orthogonally mounted triad of magnetometers and a Sun sensor onboard the spacecraft, supplemented by observations of well-located X-ray sources. The observations employed in producing this catalog were obtained over a total of 429 days between 1970 December 12 and 1973 March 18, apart from a gap between 1972 July and December when the spacecraft's transmitter was operating improperly. This online catalog was created by the HEASARC in March 2003 based on a table obtained originally from the ADC website (<a href="https://heasarc.gsfc.nasa.gov/FTP/heasarc/dbase/misc_files/uhuru4/4u.dat">https://heasarc.gsfc.nasa.gov/FTP/heasarc/dbase/misc_files/uhuru4/4u.dat</a>), which was modified by the HEASARC to include some parameters that were in the published catalog (Table 1 in the reference) but were not in the ADC table. The HEASARC made a small number of other changes and corrections to the table which are listed in the HEASARC_Implementation section of this help. Notice that the ADC table itself differs in a number of respects from the published Table 1, e.g., the comments are sometimes abbreviated and/or different, some of the names are slightly different (usually by one digit in the RA minutes part), and three of the entries have differing names and positions. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/ulxrbcat
- Title:
- Ultraluminous X-Ray Sources in External Galaxies Catalog
- Short Name:
- ULXRB
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table is a catalog of ultraluminous X-ray sources (ULXs) in external galaxies, where ULXs have been defined as compact, off-nuclear X-ray sources with X-ray luminosities in the range of 10<sup>39</sup> - 10<sup>41</sup> erg/s. The aim of this catalog is to provide easy access to the properties of ULXs, their possible counterparts at other wavelengths (optical, IR, and radio), and the properties of their host galaxies. The catalog contains 229 ULXs found in 85 galaxies which had been reported in the astronomy literature as of April 2004. Most ULXs are stellar-mass-black hole X-ray binaries, but it cannot be excluded that some ULXs might be intermediate-mass black holes. A small fraction of the candidate ULXs might be background Active Galactic Nuclei (AGN) or Supernova Remnants (SNRs). ULXs with luminosity above 10<sup>40</sup> erg/s are found in both starburst galaxies and in the halos of early-type galaxies. Some notes on individual galaxies and/or ULXs in this catalog can be found in the file <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/429/1125/notes.dat">https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/429/1125/notes.dat</a> which is available at the CDS. This table was created by the HEASARC in January 2005, based on CDS tables J/A+A/429/1125/table1a.dat and table1b.dat. It was updated in September 2012 to correct an error in the declination signs of the NGC 253 objects. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/ulxngcat
- Title:
- Ultraluminous X-Ray Sources in Nearby Galaxies Catalog
- Short Name:
- ULXNGCAT
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- One hundred and seven ultraluminous X-ray sources (ULXs) with 0.3-10.0 keV luminosities in excess of 10<sup>39</sup> erg s<sup>-1</sup> are identified in a complete sample of 127 nearby galaxies. The sample includes all galaxies within 14.5 Mpc above the completeness limits of both the Uppsala Galaxy Catalogue and the Infrared Astronomical Satellite survey. The galaxy sample spans all Hubble types, a four-decade range in mass, 7.5 < log (M/M<sub>sun</sub>) < 11.4, and in star formation rate, 0.0002 < SFR(M<sub>sun</sub> yr<sup>-1</sup>) <= 3.6. ULXs are detected in this sample at rates of one per 3.2 x 10<sup>10</sup> M<sub>sun</sub>, one per ~0.5 M<sub>sun</sub> yr<sup>-1</sup> star formation rate, and one per 57 Mpc<sup>3</sup> corresponding to a luminosity density of ~2 x 10<sup>37</sup> erg s<sup>-1</sup> Mpc<sup>-3</sup>. At these rates, the authors estimate as many as 19 additional ULXs remain undetected in fainter dwarf galaxies within the survey volume. An estimated 14 objects, or 13%, of the 107 ULX candidates are expected to be background sources. The differential ULX luminosity function shows a power-law slope alpha ~ -0.8 to -2.0 with an exponential cutoff at ~20 x 10<sup>39</sup> erg s<sup>-1</sup> with precise values depending on the model and on whether the ULX luminosities are estimated from their observed numbers of counts or, for a subset of candidates, from their spectral shapes. Extrapolating the observed luminosity function predicts at most one very luminous ULX, L<sub>X</sub> ~ 10<sup>41</sup> erg s<sup>-1</sup>, within a distance as small as 100 Mpc. The luminosity distribution of ULXs within the local universe cannot account for the recent claims of luminosities in excess of 2 x 10<sup>41</sup> erg s<sup>-1</sup>, requiring a new population class to explain these extreme objects. This table was created by the HEASARC in November 2011 based on an electronic version of Table 1 from the reference paper that was obtained from the ApJ web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/uitmaster
- Title:
- Ultraviolet Imaging Telescope Master Catalog
- Short Name:
- UITMASTER
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Ultraviolet Imaging Telescope (UIT) was one of three ultraviolet telescopes on the ASTRO-1 mission flown on the Space Shuttle Columbia during the period of 2 - 10 December 1990. The same three instruments were later flown on the Space Shuttle Endeavour during 3 - 17 March 1995, as part of the ASTRO-2 mission. Exposures were obtained on 70-mm photographic film in the 1200-3300 Angstrom range using broadband filters and later digitized using a Perkin-Elmer microdensitometer. The image resolution was 3 arcseconds over a 40 arcminute field of view and images of targets as faint as 21st (ultraviolet) magnitude were recorded. Overall, the UIT-1 mission obtained 821 exposures of 66 targets (361 near-UV and 460 far-UV), and UIT-2 obtained 758 images of 193 targets (all far-UV), for a total of 1579 exposures. This table contains only 1481 rows, 777 UIT-1 exposures (347 near-UV and 430 far-UV) and 704 UIT-2 exposures (all far-UV), implying that 98 exposures are 'missing' from this table. This table was created by the HEASARC in April 2012 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VI/104">CDS Catalog VI/104</a> file uitlist.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/uit
- Title:
- Ultraviolet Imaging Telescope Near-UV Bright Objects Catalog
- Short Name:
- UIT
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Ultraviolet Imaging Telescope (UIT) Near-UV Bright Objects Catalog is a photometric catalog of 2244 objects detected by the UIT in the near-ultraviolet (NUV; 1650A<lambda<2900A) during the Astro-1 Space Shuttle mission. Sources in the catalog are as faint as near-UV magnitude m_nuv of about 18.8, or near-UV flux f_nuv ~ 1.1x10<sup>-16ergs/s/cm</sup>2/A, but the survey is not complete to this level. Optical catalogs were used to cross identify sources and derive near-UV to Johnson V colors. A majority of the objects (88%) do indeed have proposed optical identifications from catalogs, and most are stars. The authors' purpose in creating the catalog was to form a database useful for identifying very blue objects and for performing Galactic UV stellar population studies. This database was created by the HEASARC in November 2000 based on a machine-readable version obtained from the CDS (Catalog J/ApJS/104/287). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/agileupvar
- Title:
- Updated AGILE Catalog of Bright Gamma-Ray Sources and Variability
- Short Name:
- AGILEUPVAR
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains some of the results from a variability study of a sample of bright gamma-ray (30 MeV - 50 GeV) sources. This sample is an extension of the first AGILE catalog of gamma-ray sources (1AGL), obtained using the complete set of AGILE observations in pointing mode performed during a 2.3 year period from July 9, 2007 until October 30, 2009. The dataset of AGILE pointed observations covers a long time interval and its gamma-ray data archive is useful for monitoring studies of medium-to-high brightness gamma-ray sources. In the analysis reported here, the authors used data obtained with an improved event filter that covers a wider field of view, on a much larger (about 27.5 months) dataset, integrating data on observation block (OB) time scales, which mostly range from a few days to thirty days. The data processing resulted in a better characterized source list than 1AGL was, and includes 54 sources, 7 of which are new high galactic latitude (|b_II_|>= 5 degrees) sources, 8 are new sources on the galactic plane, and 20 sources are from the previous catalogue with revised positions. Eight 1AGL sources (2 high-latitude and 6 on the galactic plane) were not detected in the final processing either because of low OB exposure and/or due to their position in complex galactic regions. The reference paper reports the results in a catalog of all the detections obtained in each single OB, including the variability results for each of these sources. In particular, the authors found that 12 sources out of 42 or 11 out of 53 are variable, depending on the variability index used, where 42 and 53 are the number of sources for which these indices could be calculated. Seven of the 11 variable sources are blazars, the others are the Crab pulsar+nebula, LS I +61 303, Cyg X-3, and 1AGLR J2021+4030. This HEASARC table contains 54 AGILE-detected sources and the main parameters of their maximum significance (defined by sqrt(TS)) detections: for each source, the name, coordinates, the sqrt(TS) value as a measure of the detection significance, the E > 100 MeV flux, the four variability indices described in Section 5 of the reference paper, the number of detections, the confirmed counterparts and source class, if any, and other possible associations ordered according to the angular distance from the AGL source are given. These data are listed in Table 5a of the reference paper. This HEASARC table does not contain the list of fluxes for these sources as measured in all of the relevant individual OBs (Table 5b in the reference paper). This latter is obtainable from the CDS: <a href="http://cdsarc.u-strasbg.fr/ftp/cats/J_A+A/558/A137/table5b.dat">http://cdsarc.u-strasbg.fr/ftp/cats/J_A+A/558/A137/table5b.dat</a>. This table was created by the HEASARC in December 2013 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/558/A137">CDS catalog J/A+A/558/A137</a> file table5a.dat. This is a service provided by NASA HEASARC .
