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15761. The WGACAT version of ROSAT sources
ID:
ivo://CDS.VizieR/IX/12
Title:
The WGACAT version of ROSAT sources
Short Name:
IX/12
Date:
21 Oct 2021
Publisher:
CDS
Description:
WGACAT is a catalogue of point sources generated at HEASARC from all the ROSAT PSPC (Position Sensitive Proportional Counter) pointing observations from Feb 1991 to March 1994. These were the files available in the public archive at HEASARC as of September 1994. This catalog is an independent research effort aimed at releasing as quickly as possible a list of sources detected by ROSAT in its pointed phase to: (1) identify the detected sources, (2) ensure their timely observation by currently active X-ray missions e.g. ASCA, (3) to search for objects which show exceptional time variability and spectral properties and (4) to provide an independent check of the detection technique used in the official ROSAT project (SAS) processing. WGACAT stands for N.E. White (HEASARC/GSFC). P. Giommi (ESA), and L. Angelini (HEASARC/GSFC)
15762. The WGACAT version of ROSAT sources
ID:
ivo://CDS.VizieR/IX/31
Title:
The WGACAT version of ROSAT sources
Short Name:
IX/31
Date:
21 Oct 2021
Publisher:
CDS
Description:
WGACAT is a point source catalogue generated from all ROSAT PSPC (Position Sensitive Proportional Counter) pointed observations. This catalog has been generated by N.E. White (HEASARC/GSFC), P. Giommi (SDC/ASI) and L. Angelini (HEASARC/GSFC) and is a private research effort, not related to the official catalogs generated by the ROSAT project. The WGACAT was made first publicly available in November 1994 through the HEASARC on-line service (White, Giommi and Angelini 1994), with a first minor revision in March 1995 (WGACAT95). It was generated using all the public ROSAT PSPC pointed data available than, corresponding to 75% of the entire set, and featured ~ 68000 detections of which 62000 were unique sources. The current version, released in May 2000, is the final and complete version of WGACAT and includes the remaining sequences not processed in the WGACAT95. WGACAT (May 2000) contains about 88,000 detections, with more than 84,000 individual sources, obtained from 4160 sequences. The catalog was generated using an optimized sliding cell detect algorithm in XIMAGE (first developed for the EXOSAT project). The inner and outer parts of the images were run separately, to maximize the sensitivity to source detection. This method is very sensitive in finding point sources, but can also find spurious sources where there is extended emission. We have visually inspected each detection, removed the obvious spurious cases and assigned a quality flag to each detection.
15763. The WHIQII survey: compact blue galaxies
ID:
ivo://CDS.VizieR/J/ApJ/708/1076
Title:
The WHIQII survey: compact blue galaxies
Short Name:
J/ApJ/708/1076
Date:
21 Oct 2021
Publisher:
CDS
Description:
As part of the WIYN High Image Quality Indiana-Irvine (WHIQII) survey, we present 123 spectra of faint emission-line galaxies, selected to focus on intermediate redshift (0.4<~z<~0.8) galaxies with blue colors that appear physically compact on the sky. The sample includes 15 true Luminous Compact Blue Galaxies (LCBGs) and an additional 27 slightly less extreme emission-line systems. These galaxies represent a highly evolving class that may play an important role in the decline of star formation since z~1, but their exact nature and evolutionary pathways remain a mystery. Here, we use emission lines to determine metallicities and ionization parameters, constraining their intrinsic properties and state of star formation. Some LCBG metallicities are consistent with a "bursting dwarf" scenario, while a substantial fraction of others are not, further confirming that LCBGs are a highly heterogeneous population but are broadly consistent with the intermediate redshift field. In agreement with previous studies, we observe overall evolution in the luminosity-metallicity relation at intermediate redshift. Our sample, and particularly the LCBGs, occupies a region in the empirical R_23_-O_32_ plane that differs from luminous local galaxies and is more consistent with dwarf irregulars at the present epoch, suggesting that cosmic "downsizing" is observable in even the most fundamental parameters that describe star formation.
15764. The 2WHSP catalog
ID:
ivo://CDS.VizieR/J/A+A/598/A17
Title:
The 2WHSP catalog
Short Name:
J/A+A/598/A17
Date:
04 Feb 2022 11:56:24
Publisher:
CDS
Description:
High Synchrotron Peaked blazars (HSPs) dominate the gamma sky at energies larger than a few GeV; however, only a few hundred blazars of this type have been catalogued so far. In this paper we present the 2WHSP sample, the largest and most complete list of HSP blazars available to date, which is an expansion of the 1WHSP catalog of gamma-ray source candidates off the Galactic plane. We cross-matched a number of multi-wavelength surveys (in the radio, infrared and X-ray bands) and applied selection criteria based on the radio to IR and IR to X-ray spectral slopes. To ensure the selection of genuine HSPs we examined the SED of each candidate and estimated the peak frequency of its synchrotron emission ({nu}_peak_) using the ASDC SED tool, including only sources with {nu}_peak_>10^15^Hz (equivalent to {nu}_peak_>4eV). We have assembled the largest and most complete catalog of HSP blazars to date, which includes 1691 sources. A number of population properties, such as infrared colours, synchrotron peak, redshift distributions, and gamma-ray spectral properties, have been used to characterise the sample and maximize completeness. We also derived the radio logN-logS distribution. This catalog has already been used to provide seeds to discover new very high energy objects within Fermi-LAT data and to look for the counterparts of neutrino and ultra high energy cosmic ray sources, showing its potential for the identification of promising high-energy gamma, sources and multi-messenger targets.
15765. The Wide-field VLBA Calibrator Survey (WFCS)
ID:
ivo://CDS.VizieR/J/AJ/161/14
Title:
The Wide-field VLBA Calibrator Survey (WFCS)
Short Name:
J/AJ/161/14
Date:
09 Mar 2022
Publisher:
CDS
Description:
This paper presents the results of the largest very long baseline interferometry (VLBI) absolute astrometry campaign to date of 13645 radio source observations with the Very Long Baseline Array. Of these, 7220 have been detected, including 6755 target sources that have never been observed with VLBI before. This makes the present VLBI catalog the largest ever published. The positions of the target sources have been determined with the median uncertainty of 1.7mas, and 15542 images of 7171 sources have been generated. Unlike previous absolute radio astrometry campaigns, observations were made at 4.3 and 7.6GHz simultaneously using a single wide-band receiver. Because of the fine spectral and time resolutions, the field of view was 4'-8'-much greater than the 10"-20" in previous surveys. This made possible the use of input catalogs with low position accuracy and the detection of a compact component in extended sources. Unlike previous absolute astrometry campaigns, both steep- and flat-spectrum sources were observed. The observations were scheduled in the so-called filler mode to fill the gaps between other high-priority programs. This was achieved by the development of the totally automatic scheduling procedure.
15766. The WIRED survey. II.
ID:
ivo://CDS.VizieR/J/ApJS/197/38
Title:
The WIRED survey. II.
Short Name:
J/ApJS/197/38
Date:
21 Oct 2021
Publisher:
CDS
Description:
With the launch of the Wide-field Infrared Survey Explorer (WISE), a new era of detecting planetary debris and brown dwarfs (BDs) around white dwarfs (WDs) has begun with the WISE InfraRed Excesses around Degenerates (WIRED) Survey. The WIRED Survey is sensitive to substellar objects and dusty debris around WDs out to distances exceeding 100pc, well beyond the completeness level of local WDs. In this paper, we present a cross-correlation of the preliminary Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) WD catalog between the WISE, Two-Micron All Sky Survey (2MASS), UKIRT Infrared Deep Sky Survey (UKIDSS), and SDSS DR7 photometric catalogs. From ~18000 input targets, there are WISE detections comprising 344 "naked" WDs (detection of the WD photosphere only), 1020 candidate WD+M dwarf binaries, 42 candidate WD+BD systems, 52 candidate WD+dust disk systems, and 69 targets with indeterminate infrared excess. We classified all of the detected targets through spectral energy distribution model fitting of the merged optical, near-IR, and WISE photometry. Some of these detections could be the result of contaminating sources within the large (~6") WISE point-spread function; we make a preliminary estimate for the rates of contamination for our WD+BD and WD+disk candidates and provide notes for each target of interest.
15767. The WISE AGN candidates catalogs
ID:
ivo://CDS.VizieR/J/ApJS/234/23
Title:
The WISE AGN candidates catalogs
Short Name:
J/ApJS/234/23
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present two large catalogs of active galactic nucleus (AGN) candidates identified across 30,093deg^2^ of extragalactic sky from the Wide-field Infrared Survey Explorer's AllWISE Data Release. Both catalogs are selected purely using the Wide-field Infrared Survey Explorer (WISE) W1 and W2 bands. The R90 catalog consists of 4,543,530 AGN candidates with 90% reliability, while the C75 catalog consists of 20,907,127 AGN candidates with 75% completeness. These reliability and completeness figures were determined from a detailed analysis of UV- to near-IR spectral energy distributions of ~10^5^ sources in the 9deg^2^ Bootes field. The AGN selection criteria are based on those of Assef+ (2013, J/ApJ/772/26) recalibrated to the AllWISE data release. We provide a detailed discussion of potential artifacts and excise portions of the sky close to the Galactic Center, Galactic Plane, nearby galaxies, and other expected contaminating sources. These catalogs are expected to enable a broad range of science, and we present a few illustrative cases. From the R90 sample, we identify 45 highly variable AGNs lacking radio counterparts in the FIRST survey. One of these sources, WISEA J142846.71+172353.1, is a changing-look quasar at z=0.104, which has changed from having broad H{alpha} to being a narrow-lined AGN. We characterize our catalogs by comparing them to large, wide-area AGN catalogs in the literature. We identify four ROSAT X-ray sources that are each matched to three WISE-selected AGNs in the R90 sample within 30". Spectroscopy reveals that one of these systems, 2RXS J150158.6+691029, consists of a triplet of quasars at z=1.133+/-0.004, suggestive of a rich group or forming galaxy cluster.
15768. The WISE catalog of Galactic HII regions
ID:
ivo://CDS.VizieR/J/ApJS/212/1
Title:
The WISE catalog of Galactic HII regions
Short Name:
J/ApJS/212/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using data from the all-sky Wide-Field Infrared Survey Explorer (WISE) satellite, we made a catalog of over 8000 Galactic HII regions and HII region candidates by searching for their characteristic mid-infrared (MIR) morphology. WISE has sufficient sensitivity to detect the MIR emission from H II regions located anywhere in the Galactic disk. We believe this is the most complete catalog yet of regions forming massive stars in the Milky Way. Of the ~8000 cataloged sources, ~1500 have measured radio recombination line (RRL) or H{alpha} emission, and are thus known to be H II regions. This sample improves on previous efforts by resolving H II region complexes into multiple sources and by removing duplicate entries. There are ~2500 candidate H II regions in the catalog that are spatially coincident with radio continuum emission. Our group's previous RRL studies show that ~95% of such targets are H II regions. We find that ~500 of these candidates are also positionally associated with known H II region complexes, so the probability of their being bona fide H II regions is even higher. At the sensitivity limits of existing surveys, ~4000 catalog sources show no radio continuum emission. Using data from the literature, we find distances for ~1500 catalog sources, and molecular velocities for ~1500H II region candidates.
15769. The WISH catalogue at 352 MHz
ID:
ivo://CDS.VizieR/VIII/69A
Title:
The WISH catalogue at 352 MHz
Short Name:
VIII/69A
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Westerbork In the Southern Hemishpere (WISH) is a low-frequency (352MHz) radio survey that covers most of the sky between -25 and -15 degrees (1.60sr) at a wavelength of 92cm to a limiting flux density of approximately 18mJy (5sigma). Due to the very low elevation of the observations, the survey has a much lower resolution in declination than in right ascension (54"x54"cosec{delta}). A correlation with the 1.4GHz NVSS (VIII/65) shows that the positional accuracy is less constrained in declination than in right ascension, but there is no significant systematic error. The correlation with the NVSS was also used to construct a sample of faint Ultra Steep Spectrum sources (file uss.dat, table 2 of the paper). This sample is aimed at increasing the number of known high redshift radio galaxies to allow detailed follow-up studies of these massive galaxies and their environments in the early Universe. WISH is a collaboration between the Netherlands Foundation for Research in Astronomy (NFRA/ASTRON) and the Leiden Observatory. Carlos De Breuck, Yuan Tang, Ger de Bruyn, Huub Rottgering, Wil van Breugel, and Roeland Rengelink. For more information, see the WENSS home page at http://www.strw.leidenuniv.nl/wenss/ or contact wenss.people@strw.leidenuniv.nl
15770. The WMAP First Year Source Catalog (WMAP1)
ID:
ivo://CDS.VizieR/J/ApJS/148/97
Title:
The WMAP First Year Source Catalog (WMAP1)
Short Name:
J/ApJS/148/97
Date:
21 Oct 2021
Publisher:
CDS
Description:
The WMAP mission has mapped the full sky to determine the geometry, content, and evolution of the universe. Full-sky maps are made in five microwave frequency bands to separate the temperature anisotropy of the cosmic microwave background (CMB) from foreground emission, including diffuse Galactic emission and Galactic and extragalactic point sources. We define masks that excise regions of high foreground emission, so CMB analyses can be carried out with minimal foreground contamination. We also present maps and spectra of the individual emission components, leading to an improved understanding of Galactic astrophysical processes.

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