데이터셋 상세
미국
Faint Images of the Radio Sky at Twenty cm (FIRST)
This catalog comprises the Faint Images of the Radio Sky at Twenty cm (FIRST) Survey. The FIRST survey began in 1993, and covers the north and south Galactic caps. The present 14Dec17 version is derived from the 1993 through 2011 observations. The catalog covers a total of about 10,575 square degrees of sky (8,444 square degrees in the north Galactic cap and 2,131 square degrees in the south Galactic cap). See the coverage maps at <a href="http://sundog.stsci.edu/first/catalogs/readme_14dec17.html#coverage">http://sundog.stsci.edu/first/catalogs/readme_14dec17.html#coverage</a> for more details of the area covered. Both the northern and southern areas were chosen to coincide approximately with the area covered by the Sloan Digital Sky Survey (SDSS). The catalog is identical to the previous version of the catalog (14Mar04) except that it has more accurate data on which sources are not covered by the SDSS DR10 catalog. Approximately 1000 sources that were indicated as covered by DR10 in the previous version are now correctly marked as not covered. The source list, radio fluxes, etc., are all the same as the 14Mar04 version. In this version of the catalog, images taken in the the new EVLA configuration have been re-reduced using shallower CLEAN thresholds in order to reduce the "CLEAN bias" in those images. Also, the EVLA images are not co-added with older VLA images to avoid problems resulting from the different frequencies and noise properties of the configurations. That leads to small gaps in the sky coverage at boundaries between the EVLA and VLA regions. As a result, the area covered by this release of the catalog is about 60 square degrees smaller than the earlier release of the catalog (13Jun05), and the total number of sources is reduced by nearly 25,000. The previous version of the catalog does have sources in the overlap regions, but their flux densities are considered unreliable due to calibration errors. The flux densities should be more accurate in this catalog, biases are smaller, and the incidence of spurious sources is also reduced. Over most of the survey area, the detection limit is 1 mJy. A region along the equatorial strip (RA = 21.3 to 3.3 hrs, Dec = -1 to 1 deg) has a deeper detection threshold because two epochs of observation were combined. The typical detection threshold in this region is 0.75 mJy. There are approximately 4,500 sources below the 1 mJy threshold used for most previous versions of the catalog. The format of this catalog is the same as releases since 13Jun05 but differs from earlier versions of the catalog. It contains two parameters which give information on the epoch of observation for each source (called mean_epoch and rms_epoch in this HEASARC version) which are described below. The P(S) parameter (called sidelobe_prob herein), which indicates the probability that the source is a sidelobe, replaces the previous binary sidelobe flag column. The parameters sdss_matches, sdss_first_offset, sdss_imag, sdss_class, twomass_matches, twomass_first_offset and twomass_kmag give information on counterparts to the FIRST source in the SDSS DR10 catalog and the 2MASS catalog, respectively. Other catalog parameters are common with FIRST catalog releases extending back over the past decade. The co-added images are available online: see the FIRST page at <a href="http://sundog.stsci.edu/first/images.html">http://sundog.stsci.edu/first/images.html</a> for details. The source catalog presented here is derived from the images. Data for the FIRST survey were collected in all VLA B-configurations from Spring 1993 through Spring 2004. For all data collected for the FIRST project, the raw u-v visibility data are placed in the VLA public archive on the day they are taken, and are available for use without restriction. Additional data in the southern Galactic cap were acquired in Spring 2009 and Spring 2011. The VLA was in a hybrid condition in 2009, with some new EVLA receivers and some old VLA receivers. The
데이터 정보
연관 데이터
20cm Radio Catalog
공공데이터포털
The 1.4-GHz Northern Sky Catalog - Version: 4 December 1991 This is the 20-cm Northern Sky Catalog of White, R. L. and Becker, R. H. (1992, Ap.J.Supp., in press) containing 30,239 sources detected from the Condon Greenbank images taken at 1.4 GHz over the declination range of -5 degrees to 82 degrees with a flux density limit of 100 mJy. This 20 cm catalog also contains the results of a cross-correlation with catalogs at 6 and 80 cm covering the northern sky between Dec=0 degrees and 70 degrees to give the spectral indices at three frequencies for about 20,000 sources. This is a service provided by NASA HEASARC .
New Catalog of Compact 20cm Sources in the Galactic Plane
공공데이터포털
This table contains the New Catalog of Compact Radio (20-cm) Sources in the Galactic Plane of White et al. (2005). Archival data were combined with more recent observations of the Galactic plane using the Very Large Array to create two new catalogs of compact centimetric radio sources. The 20-cm source catalog contained here covers a longitude range from -20 to +120 degrees in Galactic longitude l; the latitude coverage varies from b = +/- 0.8 to +/- 2.7 degrees. The total survey area is about 331 square degrees; coverage is 90% complete at a flux density threshold of about 14 mJy, and over 5000 sources are recorded. The 6-cm catalog (also available in the HEASARC Browse system as the table WBHGP6CM) covers 43 square degrees in the region -10 degrees < l <42 degrees, |b| < 0.4 degrees to a 90% completeness threshold of 2.9 mJy; over 2700 sources are found. Both surveys have an angular resolution of about 6". These catalogs provide a 30% (at 20 cm) to 50% (at 6 cm) increase in the number of high-reliability compact sources in the Galactic plane, as well as greatly improved astrometry, uniformity, and reliability; they should prove useful for comparison with new mid- and far-infrared surveys of the Milky Way. The images from which this catalog was constructed are available at the MAGPIS web site, http://third.ucllnl.org/gps This table was created by the HEASARC in July 2006 based on the combination of CDS tables J/AJ/130/586 table3.dat and table4.dat. This is a service provided by NASA HEASARC .
North Celestial Pole Region Radio Sources Detected by the 21cm Array
공공데이터포털
This table contains the catalog of 624 radio sources detected around the North Celestial Pole (NCP) with the 21 Centimeter Array (21CMA), a radio interferometer dedicated to the statistical measurement of the epoch of reionization (EoR). The data are taken from a 12-hr observation made on 2013 April 13, with a frequency coverage from 75 to 175 MHz and an angular resolution of ~4 arcminutes. The catalog includes flux densities at eight sub-bands across the 21CMA bandwidth and provides the in-band spectral indices for the detected sources. To reduce the complexity of interferometric imaging from the so-called "w" term and ionospheric effects, the present analysis is restricted to the east-west baselines within 1500 m only. 624 radio sources are found within 5 degrees around the NCP down to ~0.1 Jy (100 mJy). These source counts are compared, and also exhibit a good agreement, with deep low-frequency observations made recently with the GMRT and MWA. In particular, for fainter radio sources below ~1 Jy, the authors find a flattening trend of source counts toward lower frequencies. While the thermal noise (~0.4 mJy) is well controlled to below the confusion limit, the dynamical range (~104) and sensitivity of current 21CMA imaging are largely limited by calibration and deconvolution errors, especially the grating lobes of very bright sources, such as 3C061.1, in the NCP field, which result from the regular spacings of the 21CMA. The authors note that particular attention should be paid to the extended sources, and their modeling and removal may constitute a large technical challenge for current EoR experiments. Their analysis may serve as a useful guide to the design of next generation low-frequency interferometers like the Square Kilometre Array (SKA). The 21CMA is a ground-based radio interferometer dedicated to the detection of the EoR. The array, sited in the Ulastai valley of western China, consists of 81 pods or stations, and a total of 10,287 log-periodic antennas are deployed in two perpendicular arms along the east-west (6.1 km) (see Figure 1 in the reference paper) and north-south (4 km) directions, respectively. The spacing of these 81 pods is chosen such that a sufficiently large number of redundant baselines and a good uniform UV coverage can both be guaranteed. Each antenna element has 16 pairs of dipoles with lengths varying from 0.242 to 0.829 m, optimized to cover a frequency range of 50-200 MHz, which gives rise to an angular resolution of 3 arcminutes at 200 MHz. All of the antennas are fixed on the ground and point at the NCP for the sake of simplicity and economy. In the current work, the radio point sources observed with the 40 pods of the 21 Centimeter Array (21CMA) E-W baselines in an integration of 12 hours made on 2013 April 13 centered on the North Celestial Pole (NCP) are presented. An extra deep sample with a higher sensitivity from a longer integration time of up to years will be published later. The authors have detected a total of 624 radio sources over the central field within 3 degrees in a frequency range of 75-175 MHz band and in the outer annulus from 3-5 degrees in the 75-125 MHz band. By performing a Monte-Carlo simulation, the authors estimate a completeness of 50% at a flux density of ~0.2 Jy. This table was created by the HEASARC in May 2017 based upon the CDS Catalog J/ApJ/832/190 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 .
FIRST Catalog of FR I Radio Galaxies
공공데이터포털
The authors have built a catalog of 219 Fanaroff and Riley class I edge-darkened radio galaxies (FR Is), called FRICAT, that is selected from a published sample and obtained by combining observations from the NVSS, FIRST, and SDSS surveys. They included in the catalog the sources with an edge-darkened radio morphology, redshift <= 0.15, and extending (at the sensitivity of the FIRST images) to a radius r larger than 30 kpc from the center of the host. The authors also selected an additional sample (sFRICAT) of 14 smaller (10 < r < 30 kpc) FR Is, limiting to z < 0.05. The hosts of the FRICAT sources are all luminous (-21 >~ Mr >~ 24), red early-type galaxies with black hole masses in the range 108 <~ MBH <~ 3 x 109 solar masses); the spectroscopic classification based on the optical emission line ratios indicates that they are all low excitation galaxies. Sources in the FRICAT are then indistinguishable from the FR Is belonging to the Third Cambridge Catalogue of Radio Sources (3C) on the basis of their optical properties. Conversely, while the 3C-FR Is show a strong positive trend between radio and [O III] emission line luminosity, these two quantities are unrelated in the FRICAT sources; at a given line luminosity, they show radio luminosities spanning about two orders of magnitude and extending to much lower ratios between radio and line power than 3C-FR Is. The authors' main conclusion is that the 3C-FR Is represent just the tip of the iceberg of a much larger and diverse population of FR Is. This HEASARC table contains both the 219 radio galaxies in the main FRICAT sample listed in Table B.1 of the reference paper and the 14 radio galaxies in the additional sFRICAT sample listed in Table B.2 of the reference paper. To enable users to distinguish from which sample an entry has been taken, the HEASARC created a parameter galaxy_sample which is set to 'M' for galaxies from the main sample, and to 'S' for galaxies from the supplementary sFRICAT sample. Throughout the paper, the authors adopted a cosmology with H0 = 67.8 km s-1 Mpc-1, OmegaM = 0.308, and OmegaLambda = 0.692 (Planck Collaboration XIII 2016). This table was created by the HEASARC in February 2017 based on electronic versions of Tables B.1 and B.2 that were obtained from the Astronomy & Astrophysics website. This is a service provided by NASA HEASARC .
Multi-Array Galactic Plane Imaging Survey
공공데이터포털
FIRST Catalog of FR II Radio Galaxies
공공데이터포털
This table contains a catalog of 123 Fanaroff and Riley class II edge-brightened radio galaxies (FR IIs), called FRIICAT, that has been selected from a published sample obtained by combining observations from the NVSS, FIRST, and SDSS surveys. The catalog includes sources with redshift <=0.15, an edge-brightened radio morphology, and those with at least one of the emission peaks located at a radius r larger than 30 kpc from the center of the host. The radio luminosity at 1.4 GHz of the FRIICAT sources covers the range L1.4 ~ 1039.5 - 1042.5 erg/s. The FRIICAT catalog has 90% of low- and 10% of high-excitation galaxies (LEGs and HEGs), respectively. The properties of these two classes are significantly different. The FRIICAT LEGs are mostly luminous (-20 >~ Mr >~ -24), red early-type galaxies with black hole masses in the range 108 Msun <~ MBH <~ 109 M_sun_; they are essentially indistinguishable from the FR Is belonging to the FRICAT sample (Capetti et al. 2017, A&A, 598, A49: also available as a HEASARC table). The HEG FR IIs are associated with optically bluer and mid-IR redder hosts than the LEG FR IIs and to galaxies and black holes that are smaller, on average, by a factor of ~2. FR IIs have a factor of ~3 higher average radio luminosity than FR Is. Nonetheless, most (~90%) of the selected FR IIs have a radio power that is lower, by as much as a factor of ~100, than the transition value between FR Is and FR IIs found in the 3C sample. The correspondence between the morphological classification of FR I and FR II and the separation in radio power disappears when including sources selected at low radio flux thresholds, which is in line with previous results. In conclusion, a radio source produced by a low-power jet can be edge brightened or edge darkened, and the outcome is not related to differences in the optical properties of the host galaxy. The authors searched for FR II radio galaxies in the sample of 18,286 radio sources built by Best & Heckman (2012, MNRAS, 421, 1569) by limiting their search to the subsample of objects in which, according to these latter authors, the radio emission is produced by an active nucleus. They cross-matched the optical spectroscopic catalogs produced by the group from the Max Planck Institute for Astrophysics and Johns Hopkins University (Brinchmann et al. 2004, MNRAS, 351, 1151; Tremonti et al. 2004, ApJ, 613, 898) based on data from the Data Release 7 of the Sloan Digital Sky Survey (DR7/SDSS; Abazajian et al. 2009, ApJS, 182, 543) with the National Radio Astronomy Observatory Very Large Array Sky Survey (NVSS; Condon et al. 1998, AJ, 115, 1693, CDS Cat. VIII/65) and the Faint Images of the Radio Sky at Twenty centimeters survey (FIRST; Becker et al. 1995, ApJ, 450, 559; Helfand et al. 2015, ApJ, 801, 26, CDS Cat. VIII/92) adopting a radio flux density limit of 5 mJy in the NVSS. The authors focused on those sources with redshift z < 0.15. The majority (108) of the selected FR IIs are classified as LEG, but there are also 14 HEG and just one source that cannot be classified spectroscopically because of the lack of emission lines, namely SDSS J144625.13+214209.8. Throughout this study, the authors adopted a cosmology with H0 = 67.8 km s-1 Mpc-1, OmegaM = 0.308, and OmegaLambda = 0.692 (Planck Collaboration XIII 2016, A&A, 594, A13). This table was created by the HEASARC in May 2017 based upon the CDS Catalog J/A+A/601/A81 file table1.dat. This is a service provided by NASA HEASARC .
GLIMPSE II Epoch1 Catalog
공공데이터포털
The Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSEII) imaged longitudes ±10◦ of the central region of the Galaxy. The latitude coverage is ±1◦ from |l| =10◦to 5◦, ±1.5◦ from |l| =5◦to 2◦, and ±2◦ from |l| =2◦to 0◦. GLIMPSEII coverage excludes the Galactic center region l=±1◦, b=±0.75◦ observed by the GALCEN GO program (PID=3677). GLIMPSEII had two-epoch coverage for a total of three visits on the sky. The observations consisted of two 1.2 second integrations at each position in the first epoch of data taking (September 2005) and a single 1.2 second integration at each position six months later (April 2006).The GLIMPSEII Archive (GLMIIA or the “Archive”) consists of point sources with a signal- to-noise > 5 in at least one band and less stringent selection critera than the Catalog. The photometric uncertainty is typically < 0.3 mag. The GLIMPSEII Catalog is a subset of the Archive, but note that the entries for a particular source might not be the same due to additional nulling of magnitudes in the Catalog because of the more stringent requirements.
Phoenix Deep Survey Optical and Near-Infrared Counterparts Catalog
공공데이터포털
Using a deep Australia Telescope Compact Array (ATCA) radio survey covering an area of ~3 deg2 to a 4-sigma sensitivity of >= 100 µJy (µJy) at 1.4 GHz, the authors study the nature of faint radio galaxies. The region, 2 degrees in diameter and centered on RA and Dec (J2000.0) of 1h 14m 12.16s, -45o 44' 08.0" (Galactic latitude of -71o), is known as the Phoenix Deep Field. About 50% of the detected radio sources are identified with an optical counterpart revealed by CCD photometry to mR = 22.5 magnitudes. Near-infrared (K-band) data are also available for a selected sample of the radio sources, while spectroscopic observations have been carried out for about 40% of the optically identified sample. These provide redshifts and information on the stellar content. Emission-line ratios imply that most of the emission-line sources are star-forming galaxies, with a small contribution (~ 10%) from Seyfert 1/Seyfert 2 type objects. The authors also find a significant number of absorption-line systems, likely to be ellipticals. These dominate at high flux densities ( > 1 mJy) but are also found at sub-mJy levels. Using the Balmer decrement, they find a visual extinction AV = 1.0 for the star-forming faint radio sources. This moderate reddening is consistent with the (V - R) and (R - K) colors of the optically identified sources. For emission-line galaxies, there is a correlation between the radio power and the H-alpha luminosity, in agreement with the result of Benn et al. (1993, MNRAS, 263, 98). This suggests that the radio emission of starburst radio galaxies is a good indicator of star formation activity. When calculating luminosities, the authors assume a cosmology with a Hubble constant H0 of 50 km s-1 Mpc-1 and a deceleration parameter q0 of 0.5. This table was created by the HEASARC in June 2013 based on an electronic version of Table 1 from the reference paper, which details the photometric (optical and near-infrared), radio, spectroscopic and intrinsic properties of the faint radio sources in the PDS with established redshifts, which was obtained from the CDS web site (their catalog J/MNRAS/306/708 file table1.dat). This is a service provided by NASA HEASARC .
Sgr A* Region Compact Radio Source Catalog
공공데이터포털
Recent broad-band 34- and 44-GHz radio continuum observations of the Galactic center have revealed 41 massive stars identified with near-IR (NIR) counterparts, as well as 44 proplyd candidates within 30 arcseconds of Sgr A*. Radio observations obtained in 2011 and 2014 have been used to derive proper motions of eight young stars near Sgr A*. The accuracy of proper motion estimates based on NIR observations by Lu et al. (2009, ApJ, 690, 1463) and Paumard et al. (2006, ApJ, 643, 1011) have been investigated by using their proper motions to predict the 2014 epoch positions of NIR stars and comparing the predicted positions with those of radio counterparts in the 2014 radio observations. Predicted positions from Lu et al. show an rms scatter of 6 milliarcseconds (mas) relative to the radio positions, while those from Paumard et al. show rms residuals of 20 mas. In the reference paper, the authors also determine the mass-loss rates of 11 radio stars, finding rates that are on average ~2 times smaller than those determined from model atmosphere calculations and NIR data. Clumpiness of ionized winds would reduce the mass loss rate of WR and O stars by additional factors of 3 and 10, respectively. One important implication of this is a reduction in the expected mass accretion rate onto Sgr A* from stellar winds by nearly an order of magnitude to a value of a few x 10-7 solar masses per year. The authors carried out A-array observations of the Galactic center region (VLA program 14A-232) in the Ka (9 mm, 34.5 GHz) band on 2014 March 9 in which they detected 318 compact radio sources within 30" of Sgr A*. The authors searched for NIR counterparts to these compact radio sources using high-angular resolution AOs-assisted imaging observations acquired with the VLT/NACO. A Ks-band (central wavelength 2.18 micron) image was obtained in a rectangular dither pattern on 2012 September 12. L'-band (3.8 micron) observations were obtained during various observing runs between 2012 June and September. The authors found that 45 of the compact radio sources had stellar counterparts in the Ks and L' bands. This table contains the details of the 318 compact radio sources detected at 34.5 GHz and their NIR counterparts. This table was created by the HEASARC in November 2016 based on CDS table J/ApJ/809/10, file table6.dat. This is a service provided by NASA HEASARC .
LOFAR 2-Meter Sky Survey Preliminary Data Release Source Catalog
공공데이터포털
The Low Frequency Array (LOFAR) Two-metre Sky Survey (LoTSS) is a deep 120-168 MHz imaging survey that will eventually cover the entire Northern sky. Each of the 3,170 pointings will be observed for 8 hours, which, at most declinations, is sufficient to produce ~5-arcsec resolution images with a sensitivity of ~0.1 mJy/beam and accomplish the main scientific aims of the survey which are to explore the formation and evolution of massive black holes, galaxies, clusters of galaxies and large-scale structure. Due to the compact core and long baselines of LOFAR, the images provide excellent sensitivity to both highly extended and compact emission. For legacy value, the data are archived at high spectral and time resolution to facilitate sub-arcsecond imaging and spectral line studies. In this paper, The authors provide an overview of the LoTSS. They outline the survey strategy, the observational status, the current calibration techniques, a preliminary data release, and the anticipated scientific impact. The preliminary images that they have released were created using a fully-automated but direction-independent calibration strategy and are significantly more sensitive than those produced by any existing large-area low-frequency survey. In excess of 44,000 sources are detected in the images that have a resolution of 25-arcseconds, typical noise levels of less than 0.5 mJy/beam, and cover an area of 381 square degrees in the region of the HETDEX Spring Field (Right Ascension 10h 45m 00s to 15h 30^m ^00s and Declination +45o 00' 00" to +57o 00' 00"). Source detection on the mosaics that are centered on each pointing was performed with PyBDSM (See http://www.astron.nl/citt/pybdsm/ for more details). In an effort to minimize contamination from artifacts, the catalog was created using a conservative 7-sigma detection threshold. Furthermore, as the artifacts are predominantly in regions surrounding bright sources, the authors utilized the PyBDSM functionality to decrease the size of the box used to calculate the local noise when close to bright sources, which has the effect of increasing the estimated noise level in these regions. Their catalogs from each mosaic are merged to create a final catalogue of the entire HETDEX Spring Field region. During this process, the authors remove multiple entries for sources by only keeping sources that are detected in the mosaic centered on the pointing to which the source is closest to the center. In the catalog, they provide the type of source, for which they used PyBDSM to distinguish isolated compact sources, large complex sources, and sources that are within an island of emission that contains multiple sources. In addition, they attempted to distinguish between sources that are resolved and unresolved in their images. The authors have provided a preliminary data release from the LOFAR Two-metre Sky Survey (LoTSS). This release contains 44,500 sources which were detected with a signal in excess of seven times the local noise in their 25" resolution images. The noise varies across the surveyed region but is typically below 0.5 mJy/beam and the authors estimate the catalog to be 90% complete for sources with flux densities in excess of 3.9 mJy/beam. This table was created by the HEASARC in February 2017 based on CDS Catalog J/A+A/598/A104 file lotss.dat. This is a service provided by NASA HEASARC .