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VLA M 31 325-MHz Source Catalog
This table contains some of the results from a 325-MHz radio survey of M 31, conducted with the A configuration of the Very Large Array. The survey covered an area of 7.6 square degrees, and a total of 405 radio sources between <~ 6" and 170" in extent were mapped with a resolution of 6" and a 1-sigma sensitivity of ~ 0.6mJy/beam. For each source, its morphological class, major axis theta<sub>M</sub>, minor axis theta<sub>m</sub>, position angle theta<sub>PA</sub>, peak flux I, integrated flux density S, spectral index alpha, and spectral curvature parameter {phi were calculated. A comparison of the flux and radial distribution - both in the plane of the sky and in the plane of M 31 - of these sources with those of the XMM-Newton Large-Scale Structure Survey and the Westerbork Northern Sky Survey revealed that a vast majority of sources detected are background radio galaxies. As a result of this analysis, the authors expect that only a few sources are intrinsic to M 31. This study is based on a 5 hr (4 hr on-source) observation of M 31 conducted on 2000 December 15 with the VLA in A configuration. The procedures used to generate the source list and the source properties (essentially making use of the MIRIAD task SFIND) are discussed in Sections 2.2.2 and 2.3 of the reference paper, respectively. This table was created by the HEASARC in September 2014 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJS/155/89">CDS Catalog J/ApJS/155/89</a> file table3.dat, the GLG (Gelfand, Lazio, Gaensler) source list. This is a service provided by NASA HEASARC .
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VLA FIRST ConeSearch
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All MAST catalog holdings are available via a ConeSearch endpoint. The Very Large Array (VLA) FIRST -- Faint Images of the Radio Sky at Twenty-cm -- is a project designed to produce the radio equivalent of the Palomar Observatory Sky Survey over 10,000 square degrees of the North and South Galactic Caps. Using the NRAO Very Large Array (VLA) and an automated mapping pipeline, we produce images with 1.8" pixels, a typical rms of 0.15 mJy, and a resolution of 5". At the 1 mJy source detection threshold, there are ~90 sources per square degree, ~35% of which have resolved structure on scales from 2-30". 30% of the sources have counterparts in the Sloan Digital Sky Survey. The VLA FIRST catalog at MAST was published December 17, 2014. More information is available at http://sundog.stsci.eduAll available missions are listed at http://archive.stsci.edu/vo/mast_services.html.
M 17 Chandra X-Ray Point Source Catalog
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This table contains some of the results from a Chandra ACIS observation of the stellar populations in and around the M17 H II region. The field reveals 886 sources (listed in the present table) with observed X-ray luminosities (uncorrected for absorption) between ~ 29.3 erg s-1 < log LX < 32.8 erg s-1, 771 of which have stellar counterparts in infrared images. Spectral analysis results for the 598 brightest X-ray sources which have photometric significance of 2.0 or greater) are also given herein. For 546 of the X-ray sources, the fits used the "wabs(apec)" thermal plasma model in XSPEC assuming scaled 0.3 times solar photospheric abundances, while for the other 52 X-ray sources for which either the thermal model poorly described the data or required nonphysical parameters and the X-ray source was not identified with a known stellar counterpart, the fits used the "wabs(powerlaw)" model in XSPEC. In addition to the comprehensive tabulation of X-ray source properties, several other results were presented in the reference paper: 1. The X-ray luminosity function is calibrated to that of the Orion Nebula Cluster population to infer a total population of roughly 8000-10,000 stars in M17, one-third lying in the central NGC 6618 cluster. 2. About 40% of the ACIS sources are heavily obscured with AV > 10 mag. Some are concentrated around well-studied star-forming regions -- IRS 5/UC1, the Kleinmann-Wright Object, and M17-North -- but most are distributed across the field. As previously shown, star formation appears to be widely distributed in the molecular clouds. X-ray emission is detected from 64 of the hundreds of Class I protostar candidates that can be identified by near- and mid-infrared colors. These constitute the most likely protostar candidates known in M17. 3. The spatial distribution of X-ray stars is complex: in addition to the central NGC 6618 cluster and well-known embedded groups, we find a new embedded cluster (designated M17-X), a 2 pc long arc of young stars along the southwest edge of the M17 H II region, and 0.1 pc substructure within various populations. These structures may indicate that the populations are dynamically young. 4. All (14/14) of the known O stars but only about half (19/34) of the known B0-B3 stars in the M17 field are detected. These stars exhibit the long-reported correlation between X-ray and bolometric luminosities of LX ~ 10-7 Lbol. While many O and early-B stars show the soft X-ray emission expected from microshocks in their winds or moderately hard emission that could be caused by magnetically channeled wind shocks, six of these stars exhibit very hard thermal plasma components (kT > 4 keV) that may be due to colliding wind binaries. More than 100 candidate new OB stars are found, including 28 X-ray detected intermediate- and high-mass protostar candidates with infrared excesses. 5. Only a small fraction (perhaps 10%) of X-ray selected high- and intermediate-mass stars exhibit K-band-emitting protoplanetary disks, providing further evidence that inner disks evolve very rapidly around more massive stars. This table was created by the HEASARC in December 2007 based on electronic versions of Tables 1, 2, 3, 4 and 5 of the reference paper which were obtained from the electronic ApJ web site. This is a service provided by NASA HEASARC .
COSMOS GMRT 610 MHz Catalog
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The GMRT observations of the 2 sq. deg. COSMOS field were conducted using 30 antennas, their longest baseline being 25 km. The channel width of observations was 125 kHz, with a total bandwidth of 32 MHz.