- ID:
- ivo://CDS.VizieR/J/MNRAS/479/807
- Title:
- Catalogue of faint local radio AGN
- Short Name:
- J/MNRAS/479/807
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of 2210 local (z<0.1) galaxies that contain faint active galactic nuclei (AGN). We select these objects by identifying galaxies that exhibit a significant excess in their radio luminosities, compared to what is expected from the observed levels of star formation activity in these systems. This is achieved by comparing the optical (spectroscopic) star formation rate (SFR) to the 1.4GHz luminosity measured from the Faint Images of the Radio Sky at Twenty centimeters survey. The majority of the AGN identified in this study are fainter than those in previous work, such as in the Best and Heckman (2012, Cat. J/MNRAS/421/1569) catalogue. We show that these faint AGN make a non-negligible contribution to the radio luminosity function at low luminosities (below 10^22.5^W/Hz), and host ~13 per cent of the local radio luminosity budget. Their host galaxies are predominantly high stellar-mass systems (with a median stellar mass of 1011 M), are found across a range of environments (but typically in denser environments than star-forming galaxies) and have early-type morphologies. This study demonstrates a general technique to identify AGN in galaxy populations where reliable optical SFRs can be extracted using spectro-photometry and where radio data are also available so that a radio excess can be measured. Our results also demonstrate that it is unsafe to infer SFRs from radio emission alone, even if bright AGN have been excluded from a sample, since there is a significant population of faint radio AGN that may contaminate the radio-derived SFRs.
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- ID:
- ivo://CDS.VizieR/VIII/99
- Title:
- Catalogue of Radio Stars
- Short Name:
- VIII/99
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The first version of this catalogue was published in Abh.Hamburger Sternw. 1978, Vol.10, p 1ff. (CDS Catalogue II/129). A second version was published in 1987 (1987A&AS...69...87W) and microfiches (CDS Catalogue II/147). A third version was published 1995A&AS..109..177W (CDS Catalogue II/199). The basic concept of the earlier versions is preserved (in file "catalog.txt"), namely one entry per star per frequency per paper. Space is now provided, however, to add more informations. These may be of technical or astronomical nature. Usually month and year of observation and the number of independent data points or length of monitoring session are given. In the file "catalog.txt", all radio data are preceded by a header which contains information on the star or stellar system. (Note, that a physical stellar system is regarded as one single entry and that comments pertaining to individual components are found directly behind the observational data). Stellar data like names, position, proper motion, magnitudes and spectroscopic types are given in fixed format in a self-explanatory fashion. It is tried to have typical values from commonly available references. It is not intended to compete here with other compilations. These header informations are collected when the star is entered for the first time. They are only changed when new values are available while additional radio references are added. An arbitrarily expandable section for unformatted text finishes the header. Finally, the units of the radio data remain in MHz (column#1) and mJy (columns #2. and #3). All coordinates refer to epoch and equinox 1950.0 (e.g. B1950). This is a so-called merged version e.g. all stars, those detected at least once and those with upper limits only, are listed in order of ascending right ascension. The detected stars are marked with a "D" in the outermost right hand column in lines 1 to 5 ('D' in column "Det" of the file "stars.dat"). The last updating occurred on 2001-Mar-06. In this version stars have new running numbers.
- ID:
- ivo://CDS.VizieR/VIII/67
- Title:
- Catalogue of scintillating radio sources
- Short Name:
- VIII/67
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A surveys of compact (<1") radio sources exhibiting interplanetary scintillation were conducted at 102MHz on the Large Phased Array of the Lebedev Institute of Physics. The surveys cover a 0.047 steradian area of the 7C survey in the direction RA=6h28m and DE=45{deg} and a 0.097-steradian area in the direction RA=10h28m and DE=41{deg}. A total of 395 scintillating radio sources in a 0.144 sr region were detected.
- ID:
- ivo://CDS.VizieR/VIII/19
- Title:
- Catalogues from a deep 327 MHz Westerbork Survey
- Short Name:
- VIII/19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a deep survey of six fields with the Westerbork Synthesis Radio Telescope at 327 MHz. In total we have detected ~4500 sources brighter than our 5-sigma noise level, which ranges from 2.4-3.5 mJy/beam, over an area of ~95 square degrees. For four fields we also obtained 608 MHz observations, for the remaining two fields 608 MHz observations were already available. We present the source catalogues at both frequencies and derive source counts and spectral indices. The data were calibrated using the DWARF redundancy package and absolute calibration is based on 3C286, using a flux of 26.93 Jy at 327 Mhz and 21.47 Jy at 608 MHz. The source parameters were determined using a gaussian fitting procedure for all but the most complex sources and statistical corrections for noise bias were applied. As part of my PhD-thesis at Leiden Observatory I made the following surveys at 327 and 608 MHz using the Westerbork Synthesis Radio Telescope: -------------------------------------------------------------------------- 64W2: Lynx, 327 MHz only (this field has been mapped at this frequency before by M.J.A. Oort (thesis), I've added a 2 after the W to indicate the revised list), numbers do not correspond because the present survey is more sensitive. 69W : Draco, a survey of 2 overlapping fields at 327 MHz and 6 fields at 608 MHz. 70W : Umi, 327 MHz only, one field. 75W : OH471, one 327 MHz field and three 608 MHz fields 76W : Cam, one 327 MHz field and three 608 MHz fields -------------------------------------------------------------------------- Sources detected at both frequencies have corresponding numbers in the 327 MHz (92cm) and 608 MHz (50cm) lists. Multiple sources are indicated by a '*' after the name, their components by 'A','B', etc. Components of multiple sources do not necessarily correspond between the two frequencies, also in some cases one or more components may not be detected at the other frequency. The .tex files are in plain TeX format The .dat files were written with the following format (fortran): FORMAT(A8,1X,F9.2,1X,F4.2,1X,F9.1,1X,F4.1,1X,F8.2,1X,F7.2,1X,A2, 1 1X,F5.1,1X,F4.1,1X,F4.0,1X,F3.0,1X,F5.1,1X,F5.2,1X,F7.2, 1 1X,F5.2,1X,F5.2)
- ID:
- ivo://CDS.VizieR/J/A+A/501/801
- Title:
- CBI sample at 4.85GHz and 10.45GHz
- Short Name:
- J/A+A/501/801
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of the flux density measurements at 4.85GHz and 10.45GHz of a sample of 5998 NVSS radio sources with the Effelsberg 100m telescope. The initial motivation was the need to identify the NVSS radio sources that could potentially contribute significant contaminating flux in the frequency range at which the Cosmic Background Imager experiment operated.
- ID:
- ivo://CDS.VizieR/VIII/30
- Title:
- 5C14/5C15/5C16 Radio Survey at 408 and 1407 MHz
- Short Name:
- VIII/30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains the fourteenth, fifteenth, and sixteenth sections of the 5C Cambridge survey of radio sources. This catalog reports further 408 and 1407 MHz observations of the 5C12 area (Benn et al. 1982), which were carried out with the One-Mile Telescope at Cambridge to provide more accurate positions for the 5C12 sources and to extend the 5C12 catalog. Positions and flux densities were measured for 691 sources in a 5 degree x 5 degree area near the north galactic pole. The catalog data include the serial (source) number, right ascension (B1950.0) and declination (B1950.0), rms uncertainty in 408 MHz position, peak 408 MHz flux density and rms uncertainty, effective envelope attenuation (P_eff) at 408 MHz, difference between the 408 MHz and 1407 MHz positions, rms uncertainty in 1407 MHz position, peak 1407 MHz flux density and uncertainty, envelope attenuation P at 1407 MHz and radio spectral index between 408 MHz and 1407 MHz.
- ID:
- ivo://CDS.VizieR/J/MNRAS/457/1496
- Title:
- 10C cont.: a deeper radio survey at 15.7GHz
- Short Name:
- J/MNRAS/457/1496
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep 15.7-GHz observations made with the Arcminute Microkelvin Imager (AMI) Large Array in two fields previously observed as part of the Tenth Cambridge (10C) survey. These observations allow the source counts to be calculated down to 0.1mJy, a factor of five deeper than achieved by the 10C survey. The new source counts are consistent with the extrapolated fit to the 10C source count, and display no evidence for either steepening or flattening of the counts. There is thus no evidence for the emergence of a significant new population of sources (e.g. starforming) at 15.7GHz flux densities above 0.1mJy, the flux density level at which we expect starforming galaxies to begin to contribute. Comparisons with the de Zotti et al. model and the SKADS Simulated Sky show that they both underestimate the observed number of sources by a factor of two at this flux density level. We suggest that this is due to the flat-spectrum cores of radio galaxies contributing more significantly to the counts than predicted by the models.
- ID:
- ivo://CDS.VizieR/J/MNRAS/346/627
- Title:
- CENSORS (Combined EIS-NVSS Survey) catalog
- Short Name:
- J/MNRAS/346/627
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A new sample of radio sources, with the designated name CENSORS (A Combined EIS-NVSS Survey Of Radio Sources), has been defined by combining the National Radio Astronomy Observatory Very Large Array Sky Survey (NVSS) at 1.4GHz with the ESO Imaging Survey (EIS) Patch D, a 3x2deg^2^ region of sky centred at RA = 09 51 36.0, DE = -21 00 00 (J2000). New radio observations of 199 NVSS radio sources with NVSS flux densities S_1.4GHz_>7.8mJy are presented, and are compared with the EIS I-band imaging observations which reach a depth of I~23; optical identifications are obtained for over two-thirds of the ~150 confirmed radio sources within the EIS field.
- ID:
- ivo://CDS.VizieR/J/MNRAS/366/1265
- Title:
- CENSORS infrared imaging
- Short Name:
- J/MNRAS/366/1265
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Combined EIS-NVSS Survey of Radio Sources (CENSORS) is a 1.4-GHz radio survey selected from the National Radio Astronomy Observatories (NRAO) Very Large Array (VLA) Sky Survey (NVSS) and complete to a flux density of 7.2mJy. It targets the European Southern Observatory (ESO) Imaging Survey (EIS) Patch D, which is a 3x2{deg}^2^ field centred on right ascension 09:51:36.0 and declination 21:00:00 (J2000). This paper presents K-band imaging of 142 of the 150 CENSORS sources. The primary motivation for beginning infrared imaging of the sample was to identify the host galaxies of ~30 per cent of sources for which the EIS I-band imaging failed to produce a likely candidate. In addition, K-band magnitudes allow photometric redshift estimation and IK colours aid the identification of host galaxies (which are typically old, red ellipticals). Of the sources observed in the I and K bands, four remain undetected, possibly indicating high redshifts for the host galaxies, and eight involve complicated radio structures, or several candidate host galaxies, which have yet to be resolved. Thus, the host galaxy identifications are brought to 92 per cent completeness.
- ID:
- ivo://CDS.VizieR/J/MNRAS/416/1900
- Title:
- CENSORS + other 1.4GHz sources
- Short Name:
- J/MNRAS/416/1900
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents a new grid-based method for investigating the evolution of the steep-spectrum radio luminosity function, with the aim of quantifying the high-redshift cut-off suggested by previous work. To achieve this, the Combined EIS-NVSS Survey of Radio Sources (CENSORS) has been developed; this is a 1.4-GHz radio survey, containing 135 sources complete to a flux density of 7.2mJy, selected from the NRAO VLA Sky Survey (NVSS) over 6deg^2^ of the ESO Imaging Survey Patch D (EISD). The sample is currently 7% spectroscopically complete, with the remaining redshifts estimated via the K-z or I-z magnitude-redshift relation. CENSORS is combined with additional radio data from the Parkes All-Sky, Parkes Selected Regions, Hercules and Very Large Array (VLA) COSMOS samples to provide comprehensive coverage of the radio power versus redshift plane. The redshift distributions of these samples, together with radio source count determinations, and measurements of the local luminosity function, provide the input to the fitting process.
