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Optically-Selected QSOS NVSS-Detected Source Catalog
The authors used the 1.4-GHz NRAO VLA Sky Survey (NVSS) to study radio sources in two color-selected QSO samples: a volume-limited sample of 1,313 QSOs defined by M<sub>i</sub> < -23 in the redshift range 0.2 < z < 0.45 and a magnitude-limited sample of 2,471 QSOs with m<sub>r</sub> <= 18.5 and 1.8 < z < 2.5. About 10% were detected above the 2.4-mJy NVSS catalog limit and are powered primarily by active galactic nuclei (AGNs). The space density, rho, of the low-redshift QSOs evolves as rho ~ (1 + z)<sup>6</sup>. In both redshift ranges, the flux-density distributions and luminosity functions of QSOs stronger than 2.4 mJy are power laws, with no features to suggest more than one kind of radio source. Extrapolating the power laws to lower luminosities predicts the remaining QSOs should be extremely radio quiet, but they are not. Most were detected statistically on the NVSS images with median peak flux densities S<sub>p</sub> of ~ 0.3 mJy/beam and ~ 0.05 mJy/beam in the low- and high-redshift samples, corresponding to spectral luminosities log L<sub>1.4GHz</sub> ~ 22.7 and ~ 24.1 W/Hz, respectively. The authors suggest that the faint radio sources are powered by star formation at rates dM/dt of ~ 20 M_{sun}_/yr in the moderate luminosity (median M<sub>i</sub> of ~ -23.4) low-redshift QSOs and dM/dt ~ 500M<sub>sun</sub>/yr in the very luminous (median M<sub>i</sub> ~ -27.5) high-redshift QSOs. Such luminous starbursts (<log(L<sub>IR</sub>/L<sub>sun</sub>)> ~ 11.2 and ~ 12.6, respectively) are consistent with "quasar mode" accretion in which cold gas flows fuel both AGN and starburst. The SDSS DR7 QSO catalog (Schneider et al. 2010, AJ, 139, 2360) is complete to i = 19.1 mag over a solid angle of 2.66 sr around the North Galactic Pole. It contains the small sample of 179 color-selected QSOs defined by M<sub>i</sub> < -23 in the narrow redshift range 0.2 < z < 0.3 studied by Kimball et al. (2011, ApJ, 739, L29) and the larger sample of 1,313 QSOs in the wider redshift range 0.2 < z < 0.45 discussed here. Note that these magnitudes were calculated for an H<sub>0</sub>= 71 km/s/Mpc and Omega<sub>M</sub> = 0.27 modern flat LambdaCDM cosmology. The entire SDSS DR7 area is covered by the NVSS, whose source catalog is complete for statistical purposes above a peak flux density S<sub>p</sub> ~ 2.4 mJy/beam at 1.4 GHz. In the redshift range 0.2 < z < 0.45 the 45" FWHM (full width between half-maximum points) beam of the NVSS spans 150 - 250 kpc. There are 163 (12%) NVSS detections of the 1,313 QSOs in the redshift range 0.2 < z < 0.45 which are listed in Table 1 of the reference paper. The authors also chose a magnitude-limited sample of all 2,471 color-selected DR7 QSOs brighter than m<sub>r</sub> = 18.5 in the redshift range 1.8 < z < 2.5. The NVSS detected radio emission stronger than S = 2.4 mJy from only 191 (8%) of them: these are listed in Table 3 of the reference paper. This HEASARC table contains the contents of both samples described above. It thus has 163 + 191 = 354 entries, the sum of Tables 1 and 3 from the reference paper. To select only the entries from Table 1, the user should select entries with redshifts from 0.2 to 0.45. To select only the entries from Table 3, the user should select entries with redshifts > 1.8. This table was created by the HEASARC in January 2015 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/768/37">CDS Catalog J/ApJ/768/37</a> files table1.dat and table3.dat. This is a service provided by NASA HEASARC .
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VLA 6-GHz Observations of Low-Redshift SDSS QSOs
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This table contains results from 6-GHz Jansky Very Large Array (JVLA) observations covering a volume-limited sample of 178 low-redshift (0.2 < z <0.3) optically selected quasi-stellar objects (QSOs). These 176 radio detections fall into two clear categories: (1) about 20% are radio-loud QSOs (RLQs) with spectral luminosities of L6 >~ 1023.2 W/Hz that are primarily generated in the active galactic nucleus (AGN) responsible for the excess optical luminosity that defines a bona fide QSO; and (2) the remaining 80% that are radio-quiet QSOs (RQQs) that have 1021 <~ L6 <~ 1023.2 W/Hz and radio sizes <~ 10 kpc, and the authors suggest that the bulk of their radio emission is powered by star formation in their host galaxies. "Radio-silent" QSOs (L_6_<~ 1021 W/Hz) are rare, so most RQQ host galaxies form stars faster than the Milky Way; they are not "red and dead" ellipticals. Earlier radio observations did not have the luminosity sensitivity of L6 <~ 1021 W/Hz that is needed to distinguish between such RLQs and RQQs. Strong, generally double-sided radio emission spanning >> 10 kpc was found to be associated with 13 of the 18 RLQ cores with peak flux densities of Sp > 5 mJy/beam (log(L) >~ 24). The radio luminosity function of optically selected QSOs and the extended radio emission associated with RLQs are both inconsistent with simple "unified" models that invoke relativistic beaming from randomly oriented QSOs to explain the difference between RLQs and RQQs. Some intrinsic property of the AGN or their host galaxies must also determine whether or not a QSO appears radio-loud. The authors have reprocessed the VLA observations of a sample of SDSS QSOs discussed in Kimball et al. (2011, ApJ, 739, L29). These were obtained using the VLA C configuration with a central frequency of 6 GHz and a bandwidth of 2 GHz in each of the two circular polarizations: with natural weighting the synthesized beam width was 3.5 arcseconds FWHM. The authors generated a catalog of radio sources associated with each QSO. They detected radio emission at 6 GHz from all but two of the 178 color-selected SDSS QSOs contained in this volume-limited sample of QSOs more luminous than Mi = -23 and with redshifts 0.2 < z < 0.3. All calculations in the reference paper assume a flat LambdaCDM cosmology with H0 = 70 km s-1 Mpc-1 and OmegaLambda = 0.7. Spectral luminosities are specified by their source-frame frequencies, flux densities are specified in the observer's frame, and a mean spectral index of alpha = d(log S)/d(log nu) = -0.7 is used to make frequency conversions This table was created by the HEASARC in April 2017 based upon the CDS Catalog J/ApJ/831/168 file table1.dat. This is a service provided by NASA HEASARC .
GALEX/SDSS z=0.5-1.5 QSO Candidates Catalog
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A sample of ~60,000 objects from the combined Sloan Digital Sky Survey-Galaxy Evolution Explorer (SDSS-GALEX) database with UV-optical colors that should isolate QSOs in the redshift range 0.5 to 1.5 is discussed. The authors use SDSS spectra of a subsample of ~ 4,500 to remove stellar and galaxy contaminants in the sample to a very high level, based on the 7-band photometry. In their paper, they discuss the distributions of redshift, luminosity, and reddening of the 19,100 QSOs (~96%) that they estimate to be present in their final sample of 19,812 point sources. This latter catalog is available in the present table. This paper is based on archival data from the Galaxy Evolution Explorer (GALEX) which is operated for NASA by the California Institute of Technology under NASA contract NAS5-98034, and on data from the SDSS. This table was created by the HEASARC in March 2011 based on the electronic version of Table 2 from the reference paper which was obtained from the AJ 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 .
2dF QSO Redshift (2QZ) Survey
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The final catalog of the 2dF QSO Redshift Survey (2QZ) is based on Anglo-Australian Telescope 2dF spectroscopic observations of 44,576 color-selected (u, bJ, r) objects with 18.25 < bJ < 20.85 selected from automated plate measurement scans of UK Schmidt Telescope (UKST) photographic plates. The 2QZ comprises 23,338 quasi-stellar objects (QSOs), 12,292 galactic stars (including 2,071 white dwarfs) and 4,558 compact narrow emission-line galaxies. The authors obtained a reliable spectroscopic identification for 86 per cent of objects observed with 2dF. They also report on the 6dF QSO Redshift Survey (6QZ), based on UKST 6dF observations of 1,564 brighter (16 < bJ < 18.25) sources selected from the same photographic input catalog. In total, the authors identified 322 QSOs spectroscopically in the 6QZ. The completed 2QZ is, by more than a factor of 50, the largest homogeneous QSO catalog ever constructed at these faint limits (bJ < 20.85) and high QSO surface densities (35 QSOs/deg2). As such, it represents an important resource in the study of the Universe at moderate-to-high redshifts. The survey area comprised 30 UKST fields, arranged in two 75 degrees by 5 degrees declination strips, one passing across the South Galactic Gap centered on Dec = -30 degrees (the SGP strip), and the other across the North Galactic Gap centered on Dec = 0 degrees (referred to in the reference paper as the equatorial strip, but also known as the NGP strip. The total survey area is 721.6 deg2, when allowance is made for regions of sky excised around bright stars. Spectroscopic observations of the input catalogue were made with the 2dF instrument at the Anglo-Australian Telescope (AAT; the 2QZ sample) and the 6dF instrument at the UKST (the 6QZ sample). 2dF spectroscopic observations began in January 1997 and were completed in April 2002. Six-degree Field observations were performed over the period 2001 March-2002 September. This online catalog was created by the HEASARC in October 2010 based on the machine-readable table 2qz.dat obtained from the CDS (their catalog VII/241). This is a service provided by NASA HEASARC .
VLA SDSS Stripe 82 Survey 1.4-GHz Source Catalog
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This table contains results from a high-resolution radio survey of the Sloan Digital Sky Survey (SDSS) Southern Equatorial Stripe, also known as Stripe 82. This 1.4-GHz survey was conducted with the Very Large Array (VLA) primarily in the A configuration, with supplemental B configuration data to increase sensitivity to extended structure. The survey has an angular resolution of 1.8 arcseconds and achieves a median rms noise of 52 µJy/beam (µJy/beam) over 92 deg2. This is the deepest 1.4-GHz survey to achieve this large of an area, filling a gap in the phase space between small, deep and large, shallow surveys. It also serves as a pilot project for a larger high-resolution survey with the Expanded Very Large Array (EVLA). The authors discuss the technical design of the survey and details of the observations, and outline their method for data reduction, in the reference paper. They present a catalog of 17,969 isolated radio components, for an overall source density of ~195 sources deg-2. The astrometric accuracy of the data is excellent, with an internal check utilizing multiply observed sources yielding an rms scatter of 0.19 arcseconds in both Right Ascension and Declination. A comparison to the SDSS DR7 Quasar Catalog further confirms that the astrometry is well-tied to the optical reference frame, with mean offsets of 0.02" +/- 0.01" in Right Ascension, and 0.01" +/- 0.02" in Declination. A check of their photometry reveals a small, negative CLEAN-like bias on the level of 35 uJy. The authors report on the catalog completeness, finding that 97% of FIRST-detected quasars are recovered in the new Stripe 82 radio catalog, while faint, extended sources are more likely to be resolved out by the resolution bias. In their paper, they conclude with a discussion of the optical counterparts to the catalog sources, including 76 newly detected radio quasars. The full catalog as well as a search page and cutout server are available online at http://third.ucllnl.org/cgi-bin/stripe82cutout. The SDSS Stripe 82 observations were made with the National Radio Astronomy Observatory's (NRAO's) VLA. The data were collected over two VLA cycles, 2007-2008 and 2008-2009. The majority of the observations were taken in the A configuration, but the authors also obtained B-configuration coverage of the area in order to improve the sampling of the Fourier (U-V) plane and to increase sensitivity to the extended structure. Area 1 (delineated in black in Figure 1(a) of the paper) was covered in the A and B configurations in 2007-2008, and Area 2 (delineated in purple in Figure 1(a) of the paper) in the A and B configurations in 2008-2009. Area 1 is made up of 275 pointings, and Area 2 has 374, coming to 649 fields, and 92 deg2 covered in total. This table was created by the HEASARC in August 2013 based on a complete machine-readable version of Table 1 from the reference paper which was kindly provided by the first author. This is a service provided by NASA HEASARC .
VLA M 31 325-MHz Source Catalog
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Sunyaev-Zeldovich Array 31-GHZ Radio Source Catalog
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This table contains the first sample of 31-GHz selected sources to flux levels of 1 mJy. From late-2005 to mid-2007, the Sunyaev-Zel'dovich Array (SZA) observed 7.7 deg2 of the sky at 31 GHz to a median rms of 0.18 mJy/beam. The authors identify 209 sources at greater than 5-sigma significance in the 31-GHz maps, ranging in flux from 0.7 mJy to ~200 mJy. Archival NRAO VLA Sky Survey (NVSS) data at 1.4 GHz and observations at 5 GHz with the Very Large Array are used to characterize the sources. The authors determine the maximum-likelihood integrated source count to be N(>S) = (27.2 +/- 2.5) deg-2 * (SmJy)(-1.18 +/- 0.12) over the flux range 0.7 - 15 mJy. This result is significantly higher than predictions based on 1.4-GHz selected samples, a discrepancy which can be explained by a small shift in the spectral index distribution for faint 1.4-GHz sources. From comparison with previous measurements of sources within the central arcminute of massive clusters, the authors derive an overdensity of 6.8 +/- 4.4 deg-2, relative to field sources. The SZA is an interferometer designed specifically for detecting and imaging the Sunyaev-Zel'dovich (SZ) effect in galaxy clusters, and is located at the Owens Valley Radio Observatory (OVRO). The SZA is equipped with an 8-GHz wideband correlator and sensitive 26GHZ-36GHz receivers. The data in the SZA survey correspond to 1493 tracks taken between 2005 November 13 and 2007 July 25. The data in the CMB anisotropy measurements correspond to an additional 414 tracks taken between 2005 November 12 and 2007 October 25. The analysis in this paper refers to the full 1907 tracks taken in both observing modes. To complement the NVSS and FIRST observations, the authors obtained high-sensitivity VLA observations at 5 GHz between 2007 February 24 and 2007 April 15. This table was created by the HEASARC in June 2102 based on CDS Catalog J/ApJ/716/521 file table3.dat. 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 .
2MASS All-Sky Extended Source Catalog
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2MASS has uniformly scanned the entire sky in three near-infrared bands to detect and characterize point sources brighter than about 1 mJy in each band, with signal-to-noise ratio (SNR) greater than 1.
NRAO VLA Sky Survey Catalog
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This table contains the National Radio Astronomy Observatory (NRAO) Very Large Array (VLA) Sky Survey, the so-called NVSS Catalog. The NVSS Catalog covers the sky north of the J2000.0 Declination of -40 degrees (82% of the celestial sphere) at 1.4 GHz. The principal data products of the NVSS were (1) a set of 2326 4 degree by 4 degree continuum "cubes" with three planes containing Stokes I, Q, and U images, plus (2) a catalog of almost 2 million discrete sources stronger than a flux density S of about 2.5 mJy. The images all have 45 arcsecond FWHM angular resolution and nearly uniform sensitivity. Their rms brightness fluctuations are approximately 0.45 mJy/beam = 0.14 K (Stokes I) and approximately 0.29 mJy/beam = 0.09 K (Stokes Q and U). The rms uncertainties in right ascension and declination vary from <= ~1 arcsecond for the 400,000 sources stronger than 15 mJy to 7 arcseconds at the survey limit. The NVSS was made as a service to the astronomical community. All data products, user software, and updates were released via the World-Wide Web as soon as they were produced and verified. For more complete information on the NVSS, please refer to the NVSS website at http://www.cv.nrao.edu/nvss/ This table was created by the HEASARC in October 2002 based on the file ftp://ftp.cv.nrao.edu/nvss/CATALOG/NVSSCatalog.text.gz provided by the NVSS Catalog's authors. It was updated by the HEASARC in June 2009 to fix a problem with the original ingest in which the leading digit of some flux fields was lost. This is a service provided by NASA HEASARC .
Owens Valley Radio Observatory 40-m 31-GHZ Radio Source Catalog
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The 100m Robert C. Byrd Green Bank Telescope (GBT) and the 40m Owens Valley Radio Observatory (OVRO) telescope have been used to conduct a 31-GHz survey of 3165 known extragalactic radio sources over 143 deg2 of the sky. Target sources were selected from the NRAO VLA Sky Survey (NVSS) in fields observed by the Cosmic Background Imager (CBI); most are extragalactic active galactic nuclei (AGNs) with 1.4-GHz flux densities of 3-10 mJy. Using a maximum-likelihood analysis to obtain an unbiased estimate of the distribution of the 1.4 - 31 GHz spectral indices of these sources, the authors find a mean 31 - 1.4 GHz flux ratio of 0.110 +/- 0.003 corresponding to a spectral index alpha = -0.71+/-0.01 (Snu ~ nualpha); 9.0% +/- 0.8% of the sources have alpha > -0.5 and 1.2% +/- 0.2% have alpha > 0. By combining this spectral-index distribution with 1.4GHz source counts, the authors predict 31-GHz source counts in the range 1 mJy 31 < 4 mJy, N(>S31) = (16.7+/-1.7)deg-2(S31/1mJy)(-0.80+/-0.07). In this study, the authors present a detailed characterization of the impact of the discrete source foreground on arcminute-scale 31-GHz anisotropy measurements based upon two observational campaigns. The first campaign (the results of which are given in this table) was carried out with the OVRO 40m telescope at 31 GHz from 2000 September through 2002 December. The second campaign (the results of which are given in the GBT31GHZ table) used the GBT from 2006 February to May. A companion paper (Sievers et al. 2009arXiv0901.4540S) presents the five-year CBI total intensity power spectrum incorporating the results of the point-source measurements discussed here. Reported error bars include a 10% and 5% rms gain uncertainty for GBT and OVRO measurements, respectively. Sources detected at greater than 4 sigma at 31 GHz are flagged (detection_flag = 'Y'); for this calculation, the random gain uncertainty was excluded. In all 3165 sources were observed. The GBT catalog (the HEASARC GBT31GHZ table) contains 1490 sources. Of the 2315 useful OVRO observations many of the non-detections (and a few detections) were superceded by more sensitive GBT observations; the OVRO catalog contained in the present table therefore contains data on 1675 sources. The detection rate of the OVRO measurements was 11%, and that of the GBT measurements 25%. In all, 18% of the sources were detected at 31 GHz. This table was created by the HEASARC in June 2012 based on CDS Catalpog J/ApJ/704/1433 file table2.dat. This is a service provided by NASA HEASARC .
WISE Catalog ConeSearch
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NASA's Wide-field Infrared Survey Explorer (WISE; Wright et al. 2010) mapped the sky at 3.4, 4.6, 12, and 22 μm (W1, W2, W3, W4) in 2010 with an angular resolution of 6.1", 6.4", 6.5", and 12.0" in the four bands. WISE achieved 5σ point source sensitivities better than 0.08, 0.11, 1 and 6 mJy in unconfused regions on the ecliptic in the four bands. Sensitivity improves toward the ecliptic poles due to denser coverage and lower zodiacal background. The WISE All-Sky Release Source Catalog is mirrored at MAST and is thus available as a cone search.All available catalogs are listed at http://archive.stsci.edu/vo/mast_services.html.