- ID:
- ivo://CDS.VizieR/J/ApJS/234/2
- Title:
- The GALFA-HI survey data release 2
- Short Name:
- J/ApJS/234/2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Galactic Arecibo L-Band Feed Array HI (GALFA-HI) survey data release 2 (DR2). The survey covers the 21cm hyperfine transition of Galactic HI from -650 to 650km/s, with 0.184km/s channel spacing, 4' angular resolution, and 150mK rms noise per 1km/s velocity channel. DR2 covers the entirety of the sky available from the William E. Gordon 305m antenna at Arecibo, from decl. -1{deg}17' to decl. +37{deg}57' across all R.A.: 4 steradians or 32% of the sky. DR2 differs in a number of ways from data release 1, which was released in 2011. DR2 is built from a largely separate set of observations from DR1, which were taken in a much more consistent mode. This consistency, coupled with more careful attention to systematics and more advanced data reduction algorithms, leads to a much higher-quality DR2 data product. We present three data sets for public use: HI data cubes, far- sidelobe stray-radiation-corrected column density maps, and results of the Rolling Hough Transform linear feature detection algorithm.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/892/76
- Title:
- The GBNCC pulsar survey. V. Pulsar census
- Short Name:
- J/ApJ/892/76
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Green Bank North Celestial Cap (GBNCC) pulsar survey will cover the entire northern sky ({delta}>-40{deg}) at 350MHz, and is one of the most uniform and sensitive all-sky pulsar surveys to date. We have created a pipeline to reanalyze GBNCC survey data to take a 350MHz census of all pulsars detected by the survey, regardless of their discovery survey. Of the 1413 pulsars in the survey region, we were able to recover 670. For these we present measured signal-to-noise ratios (S/N), flux densities, pulse widths, profiles, and where appropriate, refined measurements of dispersion measures (DMs) (656 out of 670) and new or improved spectral indices (339 out of 670 total, 47 new, 292 improved). We also measure the period-pulse width relation at 350MHz to scale as W{propto}P^-0.27^. Detection scans for several hundred sources were reanalyzed in order to inspect pulsars' single pulse behavior and 223 were found to exhibit evidence of nulling. With a detailed analysis of measured and expected S/N values and the evolving radio frequency interference environment at 350MHz, we assess the GBNCC survey's sensitivity as a function of spin period, DM, and sky position. We find the sky-averaged limiting flux density of the survey to be 0.74mJy. Combining this analysis with PsrPopPy pulsar population simulations, we predict 60/5 nonrecycled/MSP discoveries in the survey's remaining 21000 pointings, and we begin to place constraints on population model parameters.
- ID:
- ivo://CDS.VizieR/J/AJ/149/162
- Title:
- The GBT 67-93.6GHz spectral line survey of Orion-KL
- Short Name:
- J/AJ/149/162
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a 67-93.6GHz spectral line survey of Orion-KL with the new 4mm Receiver on the Green Bank Telescope (GBT). The survey reaches unprecedented depths and covers the low-frequency end of the 3mm atmospheric window which has been relatively unexplored previously. The entire spectral-line survey is published electronically for general use by the astronomical community. The calibration and performance of the 4mm Receiver on the GBT is also summarized.
- ID:
- ivo://CDS.VizieR/J/A+A/556/A1
- Title:
- The 2.3GHz continuum survey of the GEM project
- Short Name:
- J/A+A/556/A1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Determining the spectral and spatial characteristics of the radio continuum of our Galaxy is an experimentally challenging endeavour for improving our understanding of the astrophysics of the interstellar medium. This knowledge has also become of paramount significance for cosmology, since Galactic emission is the main source of astrophysical contamination in measurements of the Cosmic Microwave Background radiation. In this paper we present the scope of the Galactic Emission Mapping (GEM) project and its results at 2.3GHz. Its observational program was conceived and developed to reveal the large scale properties of Galactic synchrotron radiation in total intensity and polarisation through a self-consistent set of radio continuum surveys between 408MHz and 10GHz. GEM's unique observational strategy and experimental design aim at the production of foreground templates in order to address the mutual inconsistencies between existing surveys.
- ID:
- ivo://CDS.VizieR/VIII/105
- Title:
- The GLEAM 4-Jy (G4Jy) Sample
- Short Name:
- VIII/105
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Murchison Widefield Array (MWA) has observed the entire southern sky (Declination, {delta}<30{deg}) at low radio-frequencies, over the range 72-231MHz. These observations constitute the GaLactic and Extragalactic All-sky MWA (GLEAM) Survey, and we use the extragalactic catalogue (Galactic latitude, |b|>10{deg}) to define the GLEAM 4-Jy (G4Jy) Sample. This is a complete sample of the 'brightest' radio-sources (S_151MHz_>4Jy), the majority of which are active galactic nuclei with powerful radio-jets. Crucially, low-frequency observations allow the selection of such sources in an orientation-independent way (i.e. minimising the bias caused by Doppler boosting, inherent in high-frequency surveys). We then use higher-resolution radio images, and information at other wavelengths, to morphologically classify the brightest components in GLEAM. We also conduct cross-checks against the literature, and perform internal matching, in order to improve sample completeness (which is estimated to be >95.5%). This results in a catalogue of 1,863 sources, making the G4Jy Sample over 10 times larger than that of the revised Third Cambridge Catalogue of Radio Sources (3CRR; S_178MHz_>10.9Jy). Of these G4Jy sources, 78 are resolved by the MWA (Phase-I) synthesised beam (~2' at 200MHz), and we label 67% of the sample as 'single', 26% as 'double', 4% as 'triple', and 3% as having 'complex' morphology at ~1GHz (45" resolution). We characterise the spectral behaviour of these objects in the radio, and find that the median spectral-index is {alpha}=-0.740+/-0.012 between 151MHz and 843MHz, and {alpha}=-0.786+/-0.006 between 151MHz and 1400MHz (assuming a power-law description, S_{nu}_{prop.to}{nu}^{alpha}^), compared to {alpha}=-0.829+/-0.006 within the GLEAM band. Alongside this, our value-added catalogue provides mid-infrared source associations (subject to 6" resolution at 3.4um) for the radio emission, as identified through visual inspection and thorough checks against the literature. As such, the G4Jy Sample can be used as a reliable training set for cross-identification via machine-learning algorithms. We also estimate the angular size of the sources, based on their associated components at ~1GHz, and perform a flux-density comparison for 67 G4Jy sources that overlap with 3CRR. Analysis of multi-wavelength data, and spectral curvature between 72MHz and 20GHz, will be presented in subsequent papers, and details for accessing all G4Jy overlays are provided at https://github.com/svw26/G4Jy.
- 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.
- 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.
1828. 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).
1829. 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.
