- ID:
- ivo://CDS.VizieR/J/A+A/598/A78
- Title:
- The GMRT 150MHz all-sky radio survey
- Short Name:
- J/A+A/598/A78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first full release of a survey of the 150MHz radio sky, observed with the Giant Metrewave Radio Telescope (GMRT) between April 2010 and March 2012 as part of the TIFR GMRT Sky Survey (TGSS) project. Aimed at producing a reliable compact source survey, our automated data reduction pipeline efficiently processed more than 2000h of observations with minimal human interaction. Through application of innovative techniques such as image-based flagging, direction-dependent calibration of ionospheric phase errors, correcting for systematic offsets in antenna pointing, and improving the primary beam model, we created good quality images for over 95 percent of the 5336 pointings. Our data release covers 36900deg^2^ (or 3.6{pi}steradians) of the sky between -53{deg} and +90{deg} declination (Dec), which is 90 percent of the total sky. The majority of pointing images have a noise level below 5mJy/beam with an approximate resolution of 25"x25" (or 25"x25"/cos(Dec-19{deg}) for pointings south of 19{deg} declination). We have produced a catalog of 0.62 Million radio sources derived from an initial, high reliability source extraction at the seven sigma level. For the bulk of the survey, the measured overall astrometric accuracy is better than two arcseconds in right ascension and declination, while the flux density accuracy is estimated at approximately ten percent. Within the scope of the TGSS alternative data release (TGSS ADR) project, the source catalog, as well as 5336 mosaic images (5{deg}x5{deg}) and an image cutout service, are made publicly available at the CDS as a service to the astronomical community. Next to enabling a wide range of different scientific investigations, we anticipate that these survey products will provide a solid reference for various new low-frequency radio aperture array telescopes (LOFAR, LWA, MWA, SKA-low), and can play an important role in characterizing the epoch-of-reionisation (EoR) foreground. The TGSS ADR project aims at continuously improving the quality of the survey data products. Near-future improvements include replacement of bright source snapshot images with archival targeted observations, using new observations to fill the holes in sky coverage and replace very poor quality observational data, and an improved flux calibration strategy for less severely affected observational data.
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- ID:
- ivo://CDS.VizieR/J/ApJS/252/15
- Title:
- The GNRIS-Distant Quasar Survey (GNRIS-DQS)
- Short Name:
- J/ApJS/252/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present spectroscopic measurements for 226 sources from the Gemini Near Infrared Spectrograph-Distant Quasar Survey (GNIRS-DQS). Being the largest uniform, homogeneous survey of its kind, it represents a flux-limited sample (m_i_<~19.0mag, H<~16.5mag) of Sloan Digital Sky Survey (SDSS) quasars at 1.5<~z<~3.5 with a monochromatic luminosity ({lambda}L_{lambda}_) at 5100{AA} in the range of 10^44^-10^46^erg/s. A combination of the GNIRS and SDSS spectra covers principal quasar diagnostic features, chiefly the CIV{lambda}1549, MgII{lambda}{lambda}2798,2803, H{beta}{lambda}4861, and [OIII]{lambda}{lambda}4959,5007 emission lines, in each source. The spectral inventory will be utilized primarily to develop prescriptions for obtaining more accurate and precise redshifts, black hole masses, and accretion rates for all quasars. Additionally, the measurements will facilitate an understanding of the dependence of rest-frame ultraviolet-optical spectral properties of quasars on redshift, luminosity, and Eddington ratio, and test whether the physical properties of the quasar central engine evolve over cosmic time.
2003. The Green Bank Survey
- ID:
- ivo://CDS.VizieR/VIII/53
- Title:
- The Green Bank Survey
- Short Name:
- VIII/53
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog presents the parts I, II, and III of the Green Bank survey of extragalactic radio sources at 1400 MHz. The data were obtained with the 300' antenna, producing a beamwidth of 10'x11' FWHM. Part I of the survey covers about 521 square degrees of the sky with RA from 7h17m to 16h23m, DEC from +45.8{deg} to +51.7{deg}. 1086 sources are presented down to a limiting flux density of 90 mJy. These data were originally published in Maslowski, 1972, Acta Astronomica, 22, 227 (1972AcA....22..227M). Part II of the survey covers 0.28 sr of the sky with RA from 7h08m to 16h57m, DEC from +31.9{deg} to +39.7{deg}. 2022 sources are presented down to a limiting flux density of 0.09 mJy. Spectral indices between 1400 MHz and 408 MHz are determined for most sources by comparison with the B2 source catalog (Cat.<VIII/36>). These data were originally published in Machalski 1978, Acta Astronomica, 28, 367 (1978AcA....28..367M) Part III of the survey covers an area of 0.099 sr at declinations between 70 and 76.8 degrees. This catalog contains a total of 676 radio sources, of which 502 are statistically complete to 112 mJy. These data were originally published as Rys and Machalski, 1987, Acta Astronomica, 37, 163 (1987AcA....37..163R).
2004. The GSH Binary Survey
- ID:
- ivo://CDS.VizieR/J/AN/338/61
- Title:
- The GSH Binary Survey
- Short Name:
- J/AN/338/61
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Since 2009 the Grossschwabhausen binary survey is carried out at the University Observatory Jena. This new imaging survey uses available time slots during photometric monitoring campaigns, caused by non-photometric weather conditions, which often exhibit a good atmospheric seeing. The goal of the project is to obtain current relative astrometric measurements of binary systems, that are listed in the Washington Visual Double Star Catalog. In this paper we characterize the target sample of the survey, describe the imaging observations, the astrometric measurements including the astrometric calibration, and present relative astrometric measures of all binaries, which could be obtained in the course of the survey, so far.
- ID:
- ivo://CDS.VizieR/I/353
- Title:
- The Guide Star Catalog, Version 2.4.2 (GSC2.4.2)
- Short Name:
- I/353
- Date:
- 01 Mar 2022
- Publisher:
- CDS
- Description:
- The GSC II is an all-sky catalog based on 1" resolution scans of the photographic Sky Survey plates, at two epochs and three bandpasses, from the Palomar and UK Schmidt telescopes (DSS). Positions, magnitudes, and classifications are produced for all objects on each plate. The objects are then loaded into the COMPASS database, where multiple observations of the same object are matched and assigned a unique name. GSC 2.4.1 is the first release of the augmented GSC by adding object parameters (and new objects) from deeper surveys. - GSC 2.4.0 - UCAC5 (proper motions for GAIA sources - no new objects) - APASS dr9 (optical photometry - no new objects added) - 2MASS+6x (IR photometry, classifications + positions of new objects) - SDSS dr13 (optical photometry, classifications + positions of new objects) - VISTA - VHS dr4 (IR photometry, classifications + positions of new objects) - VISTA - VIKING dr2 (IR photometry, classifications + positions of new objects) - VST - ATLAS dr3 (optical photometry, classifications + positions of new objects) - VST - KIDS dr3 (optical photometry, classifications + positions of new objects) GSC 2.4.1.2 Added the following catalogs - PanSTARRS dr1/2 - SMSS dr1 - WISE - GALEX - ultraVISTA GSC 2.4.2 has the astrometric information updated to GAIAdr2 and became the default operational catalog mid-December 2020.
- ID:
- ivo://CDS.VizieR/I/305
- Title:
- The Guide Star Catalog, Version 2.3.2 (GSC2.3)
- Short Name:
- I/305
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The GSC II is an all-sky catalog based on 1" resolution scans of the photographic Sky Survey plates, at two epochs and three bandpasses, from the Palomar and UK Schmidt telescopes (DSS). Positions, magnitudes, and classifications are produced for all objects on each plate. The objects are then loaded into the COMPASS database, where multiple observations of the same object are matched and assigned a unique name. The GSC2.3 has no magnitude limit. The parameters of the bright objects, overexposed on the Schmidt plates, are taken from the Tycho-2 (I/259) catalog. The computed proper motions are not yet publically available because of 10mas/year systematic errors discovered for the southern hemisphere that are still under investigation.
- ID:
- ivo://CDS.VizieR/I/271
- Title:
- The Guide Star Catalog, Version 2.2 (GSC2.2)
- Short Name:
- I/271
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The GSC II is an all-sky catalog based on 1" resolution scans of the photographic Sky Survey plates, at two epochs and three bandpasses, from the Palomar and UK Schmidt telescopes (DSS). Positions, magnitudes, and classifications are produced for all objects on each plate. The objects are then loaded into the COMPASS database, where multiple observations of the same object are matched and assigned a unique name. The GSC2.2 is a preliminary version of GSC II generated to support telescope operations at the GEMINI and VLT telescopes. The magnitude limits are 18.5 in photographic F (red) or 19.5 in photographic J (blue) or V. The parameters of the bright objects, overexposed on the Schmidt plates, are taken from the Tycho-2 (I/259) catalog. The final version (GSC 2.3), expected to be released in 2002, will also contain proper motions.
- ID:
- ivo://CDS.VizieR/J/AJ/127/180
- Title:
- The Hawaii Hubble Deep Field North
- Short Name:
- J/AJ/127/180
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have conducted a deep multicolor imaging survey of 0.2deg^2^ centered on the Hubble Deep Field North (HDF-N). We shall refer to this region as the Hawaii HDF-N. Deep data were collected in U, B, V, R, I, and z' bands over the central 0.2deg^2^ and in HK' over a smaller region covering the Chandra Deep Field North. The data were reduced to have accurate relative photometry and astrometry across the entire field to facilitate photometric redshifts and spectroscopic follow-up. We have compiled a catalog of 48858 objects in the central 0.2deg^2^ detected at 5{sigma} significance in a 3" aperture in either R or z' band. Number counts and color-magnitude diagrams are presented and shown to be consistent with previous observations. Using color selection we have measured the density of objects at 3<z<7. Our multicolor data indicates that samples selected at z>5.5 using the Lyman break technique suffer from more contamination by low-redshift objects than suggested by previous studies.
- ID:
- ivo://nasa.heasarc/skyview/hawaii-hdf-b
- Title:
- The Hawaii Hubble Deep Field North: Band B
- Short Name:
- Hawaii HDF B
- Date:
- 25 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Hawaii-HDF-N is an intensive multi-color imaging survey of 0.2 sq. degrees centered on the HDF-N. Data were collected on the NOAO 4m Mayall telescope, the National Astronomical Observatory of Japan 8.2m Subaru telescope and the University of Hawaii 2.2m telescope. Deep U, B, V, R, I, and z' data were obtained over the whole field and deep HK' data over the Chandra Deep Field North. Details are available in the references. [Adapted from reference website.] <P> Two different images are given in the V band (V0201 and V0401) from observations separated by about a month that had substantial differences in seeing. Provenance: Data downloaded from the reference website. A formatting error in the FITS files was corrected.. This is a service of NASA HEASARC.
- ID:
- ivo://CDS.VizieR/J/A+A/570/A11
- Title:
- The Hawk-I UDS and GOODS Survey (HUGS)
- Short Name:
- J/A+A/570/A11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a new, ultra-deep, near-infrared imaging survey executed with the Hawk-I imager at the ESO VLT, of which we make all the data (images and catalog) public. This survey, named HUGS (Hawk-I UDS and GOODS Survey), provides deep, high-quality imaging in the K and Y bands over the portions of the UKIDSS UDS and GOODS-South fields covered by the CANDELS HST WFC3/IR survey. In this paper we describe the survey strategy, the observational campaign, the data reduction process, and the data quality. We show that, thanks to exquisite image quality and extremely long exposure times, HUGS delivers the deepest K-band images ever collected over areas of cosmological interest, and in general ideally complements the CANDELS data set in terms of image quality and depth. In the GOODS-S field, the K-band observations cover the whole CANDELS area with a complex geometry made of 6 different, partly overlapping pointings, in order to best match the deep and wide areas of CANDELS imaging. In the deepest region (which includes most of the Hubble Ultra Deep Field) exposure times exceed 80 hours of integration, yielding a 1-{sigma} magnitude limit per square arcsec of ~=28.0ABmag. The seeing is exceptional and homogeneous across the various pointings, confined to the range 0.38-0.43arcsec. In the UDS field the survey is about one magnitude shallower (to match the correspondingly shallower depth of the CANDELS images) but includes also Y-band band imaging (which, in the UDS, was not provided by the CANDELS WFC3/IR imaging). In the K-band, with an average exposure time of 13 hours, and seeing in the range 0.37-0.43arcsec, the 1-{sigma} limit per square arcsec in the UDS imaging is ~=27.3ABmag. In the Y-band, with an average exposure time ~=8h, and seeing in the range 0.45-0.5arcsec, the imaging yields a 1-{sigma} limit per square arcsec of ~=28.3ABmag. We show that the HUGS observations are well matched to the depth of the CANDELS WFC3/IR data, since the majority of even the faintest galaxies detected in the CANDELS H-band images are also detected in HUGS. Finally we present the K-band galaxy number counts produced by combining the HUGS data from the two fields. We show that the slope of the number counts depends sensitively on the assumed distribution of galaxy sizes, with potential impact on the estimated extra-galactic background light.