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551. FIR properties of SDSS 0.1<z<5 quasars
ID:
ivo://CDS.VizieR/J/ApJ/811/58
Title:
FIR properties of SDSS 0.1<z<5 quasars
Short Name:
J/ApJ/811/58
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using the public data from the Herschel wide-field surveys, we study the far-infrared properties of optical-selected quasars from the Sloan Digital Sky Survey. Within the common area of ~172deg^2^, we have identified the far-infrared counterparts for 354 quasars, among which 134 are highly secure detections in the Herschel 250um band (signal-to-noise ratios >=5). This sample is the largest far-infrared quasar sample of its kind, and spans a wide redshift range of 0.14<=z<=4.7. Their far-infrared spectral energy distributions, which are due to the cold-dust components within the host galaxies, are consistent with being heated by active star formation. In most cases (>~80%), their total infrared luminosities as inferred from only their far-infrared emissions (L_IR_^(cd)^) already exceed 10^12^L_{sun}_, and thus these objects qualify as ultra-luminous infrared galaxies. There is no correlation between L_IR_^(cd)^ and the absolute magnitudes, the black hole masses or the X-ray luminosities of the quasars, which further support that their far-infrared emissions are not due to their active galactic nuclei. A large fraction of these objects (>~50%-60%) have star-formation rates >~300M_{sun}_/yr. Such extreme starbursts among optical quasars, however, is only a few percent. This fraction varies with redshift, and peaks at around z~2. Among the entire sample, 136 objects have secure estimates of their cold-dust temperatures (T), and we find that there is a dramatic increasing trend of T with increasing L_IR_^(cd)^. We interpret this trend as the envelope of the general distribution of infrared galaxies on the (T, L_IR_^(cd)^) plane.
552. First AGILE catalog of gamma-ray sources
ID:
ivo://CDS.VizieR/J/A+A/506/1563
Title:
First AGILE catalog of gamma-ray sources
Short Name:
J/A+A/506/1563
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first catalog of high-confidence {gamma}-ray sources detected by the AGILE satellite during observations performed from July 9, 2007 to June 30, 2008. Cataloged sources were detected by merging all the available data over the entire time period. AGILE, launched in April 2007, is an ASI mission devoted to {gamma}-ray observations in the 30MeV-50GeV energy range, with simultaneous X-ray imaging capability in the 18-60keV band. This catalog is based on Gamma-Ray Imaging Detector (GRID) data for energies greater than 100MeV. For the first AGILE catalog, we adopted a conservative analysis, with a high-quality event filter optimized to select {gamma}-ray events within the central zone of the instrument field of view (radius of 40{deg}). This is a significance-limited (4{sigma}) catalog, and it is not a complete flux-limited sample due to the non-uniform first-year AGILE sky coverage. The catalog includes 47 sources, 21 of which are associated with confirmed or candidate pulsars, 13 with blazars (7 FSRQ, 4 BL Lacs, 2 unknown type), 2 with HMXRBs, 2 with SNRs, 1 with a colliding-wind binary system, and 8 with unidentified sources.
553. FIRST-APM Source Catalog
ID:
ivo://CDS.VizieR/J/ApJS/143/1
Title:
FIRST-APM Source Catalog
Short Name:
J/ApJS/143/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe a program to identify optical counterparts to radio sources from the VLA FIRST survey using the Cambridge APM scans of the POSS-I plates. We use radio observations covering 4150deg^2^ of the north Galactic cap to a 20cm flux density threshold of 1.0mJy; the 382,892 sources detected all have positional uncertainties of <1" (radius of 90% confidence). Our description of the APM catalog, derived from the 148 POSS-I O and E plates covering this region, includes an assessment of its astrometric and photometric accuracy, a photometric recalibration using the Minnesota APS catalog, a discussion of the classification algorithm, and quantitative tests of the catalog's reliability and completeness. We go on to show how the use of FIRST sources as astrometric standards allows us to improve the absolute astrometry of the POSS plates by nearly an order of magnitude to ~0.15" rms. Matching the radio and optical catalogs yields counterparts for over 70,000 radio sources; we include detailed discussions of the reliability and completeness of these identifications as a function of optical and radio morphology, optical magnitude and color, and radio flux density. An analysis of the problem of radio sources with complex morphologies (e.g., double-lobed radio galaxies) is included. We conclude with a brief discussion of the source classes represented among the radio sources with identified counterparts.
554. First COMPTEL source catalogue
ID:
ivo://CDS.VizieR/J/A+AS/143/145
Title:
First COMPTEL source catalogue
Short Name:
J/A+AS/143/145
Date:
21 Oct 2021
Publisher:
CDS
Description:
The imaging Compton telescope COMPTEL aboard NASA's Compton Gamma-Ray Observatory (CGRO) has opened the MeV gamma-ray band as a new window to astronomy. COMPTEL provided the first complete all-sky survey in the energy range 0.75 to 30MeV. The catalogue, presented here, is largely restricted to published results. It contains firm as well as marginal detections of continuum and line emitting sources and presents upper limits for various types of objects. The numbers of the most significant detections are 32 for steady sources and 31 for gamma-ray bursters. Among the continuum sources, detected so far, are spin-down pulsars, stellar black-hole candidates, supernova remnants, interstellar clouds, nuclei of active galaxies, gamma-ray bursters, and the Sun during solar flares. Line detections have been made in the light of the 1.809MeV ^26^Al line, the 1.157MeV ^44^Ti line, the 847 and 1238keV ^56^Co lines, and the neutron capture line at 2.223MeV. For the identification of galactic sources, a modelling of the diffuse galactic emission is essential. Such a modelling at this time does not yet exist at the required degree of accuracy. Therefore, a second COMPTEL source catalogue will be produced after a detailed and accurate modelling of the diffuse interstellar emission has become possible.
555. First DENIS I-band extragalactic catalog
ID:
ivo://CDS.VizieR/J/A+AS/135/133
Title:
First DENIS I-band extragalactic catalog
Short Name:
J/A+AS/135/133
Date:
21 Oct 2021
Publisher:
CDS
Description:
REDCAT is the release of the provisional extragalactic catalogue constructed from the "Deep Near Infrared Southern Sky Survey" (DENIS). This catalogue contains 20260 galaxies with coordinates and I-band photometry (magnitude, diameter, axis ratio, position angle and a parameter related to the morphological type). In this new version photometric parameters are homogeneized to I-band measurements by Mathewson and Ford (1997, Cat. <J/ApJS/107/97>). Additional information on galaxies cross-identified with known objects can be obtained through the LEDA database at: http://www-obs.univ-lyon1.fr/leda/leda-consult.html This catalogue is the result of a tremendous work done along the chain Chile-Paris-Lyon. Many people are involved in this programm conducted by the P.I. N. Epchtein. We will not take the risk to mention them all. Their names will appear in forthcoming papers. The distribution on the sky is made of strips of 30 degrees in declination (180 frames per strip) south of +02{deg}. If you are satisfied with this catalogue, try to push the Community to support the DENIS project. Your suggestions are welcome for any improvement of this first release.
556. First IBIS Catalog: 20-100keV
ID:
ivo://CDS.VizieR/J/ApJ/607/L33
Title:
First IBIS Catalog: 20-100keV
Short Name:
J/ApJ/607/L33
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the first high-energy survey catalog obtained with the IBIS gamma-ray imager on board INTEGRAL. The analysis has been performed on the first-year Core Program ISGRI data comprising both Galactic Plane Scan and Galactic Centre Deep Exposure pointings for a total exposure time exceeding 5Ms. This initial survey has revealed the presence of ~120 sources detected with the unprecedented sensitivity of ~1mCrab in the energy range 20-100keV. Each source is located to an accuracy between 1' and 3', depending on its brightness. The outstanding IBIS capability to locate soft {gamma}-ray emitters has allowed us to identify most of the detected sources with already known Galactic X-ray binary systems, while 28 of the objects are of unknown nature.
557. FIRST-2MASS dust-reddened QSO spectra
ID:
ivo://CDS.VizieR/J/ApJ/757/51
Title:
FIRST-2MASS dust-reddened QSO spectra
Short Name:
J/ApJ/757/51
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a sample of 120 dust-reddened quasars identified by matching radio sources detected at 1.4GHz in the Faint Images of the Radio Sky at Twenty Centimeters survey (FIRST) with the near-infrared Two Micron All Sky Survey catalog (2MASS) and color-selecting red sources. Optical and/or near-infrared spectroscopy provide broad wavelength sampling of their spectral energy distributions that we use to determine their reddening, characterized by E(B-V). We demonstrate that the reddening in these quasars is best described by Small-Magellanic-Cloud-like dust. This sample spans a wide range in redshift and reddening (0.1<~z<~3, 0.1<~E(B-V)<~1.5), which we use to investigate the possible correlation of luminosity with reddening. At every redshift, dust-reddened quasars are intrinsically the most luminous quasars. We interpret this result in the context of merger-driven quasar/galaxy co-evolution where these reddened quasars are revealing an emergent phase during which the heavily obscured quasar is shedding its cocoon of dust prior to becoming a "normal" blue quasar. When correcting for extinction, we find that, depending on how the parent population is defined, these red quasars make up <~15%-20% of the luminous quasar population. We estimate, based on the fraction of objects in this phase, that its duration is 15%-20% as long as the unobscured, blue quasar phase.
558. FIRST-2MASS red quasar survey
ID:
ivo://CDS.VizieR/J/ApJ/667/673
Title:
FIRST-2MASS red quasar survey
Short Name:
J/ApJ/667/673
Date:
21 Oct 2021
Publisher:
CDS
Description:
Combining radio observations with optical and infrared color selection, demonstrated in our pilot study to be an efficient selection algorithm for finding red quasars, we have obtained optical and infrared spectroscopy for 120 objects in a complete sample of 156 candidates from a sky area of 2716deg^2^.
559. FIRST-NVSS-SDSS AGN sample catalog
ID:
ivo://CDS.VizieR/J/ApJ/699/L43
Title:
FIRST-NVSS-SDSS AGN sample catalog
Short Name:
J/ApJ/699/L43
Date:
21 Oct 2021
Publisher:
CDS
Description:
Radio outflows of active galactic nuclei (AGNs) are invoked in cosmological models as a key feedback mechanism in the latest phases of massive galaxy formation. Recently, it has been suggested that the two major radio AGN populations-the powerful high-excitation, and the weak low-excitation radio AGNs (HERAGN and LERAGN, respectively)-represent two earlier and later stages of massive galaxy buildup. To test this, here we make use of a local (0.04<z<0.1) sample of ~500 radio AGNs with available optical spectroscopy, drawn from the FIRST, NVSS, SDSS, and 3CRR surveys.
560. First release of the MaNGA Stellar Library (MaStar)
ID:
ivo://CDS.VizieR/J/ApJ/883/175
Title:
First release of the MaNGA Stellar Library (MaStar)
Short Name:
J/ApJ/883/175
Date:
29 Nov 2021 07:46:33
Publisher:
CDS
Description:
We present the first release of the MaNGA Stellar Library (MaStar), which is a large, well-calibrated, high-quality empirical library covering the wavelength range 3622-10354{AA} at a resolving power of R~1800. The spectra were obtained using the same instrument as used by the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) project, by piggybacking on the Sloan Digital Sky Survey (SDSS-IV)/Apache Point Observatory Galaxy Evolution Experiment 2-N (APOGEE-2N) observations. Compared to previous empirical libraries, the MaStar library will have a higher number of stars and a more comprehensive stellar-parameter coverage, especially of cool dwarfs, low-metallicity stars, and stars with different [{alpha}/Fe], achieved by a sophisticated target-selection strategy that takes advantage of stellar-parameter catalogs from the literature. This empirical library will provide a new basis for stellar-population synthesis and is particularly well suited for stellar-population analysis of MaNGA galaxies. The first version of the library contains 8646 high-quality per-visit spectra for 3321 unique stars. Compared to photometry, the relative flux calibration of the library is accurate to 3.9% in g-r, 2.7% in r-i, and 2.2% in i-z. The data are released as part of SDSS Data Release 15. We expect the final release of the library to contain more than 10000 stars.