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1501. Radio observations of the HDFS region. IV.
ID:
ivo://CDS.VizieR/J/AJ/135/2470
Title:
Radio observations of the HDFS region. IV.
Short Name:
J/AJ/135/2470
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Australia Telescope Hubble Deep Field-South (ATHDF-S) survey of the Hubble Deep Field-South (HDF-S) reaches sensitivities of ~10uJy at 1.4, 2.5, 5.2, and 8.7GHz, making the ATHDF-S one of the deepest surveys ever performed with the Australia Telescope Compact Array (ATCA). Here, we present the optical identifications of the ATHDF-S radio sources using data from the literature. We find that ~66% of the radio sources have optical counterparts to I=23.5mag. Deep Hubble Space Telescope (HST) imaging of the area identifies a further 12% of radio sources. We present new spectroscopic observations for 98 of the radio sources and supplement these spectroscopic redshifts with photometric ones calculated from five-band optical imaging.
1502. Radio properties of z < 0.3 quasars
ID:
ivo://CDS.VizieR/J/MNRAS/466/921
Title:
Radio properties of z < 0.3 quasars
Short Name:
J/MNRAS/466/921
Date:
21 Oct 2021
Publisher:
CDS
Description:
To better constrain the hypotheses proposed to explain why only a few quasars are radio loud (R_L_), we compare the characteristics of 1958 nearby (z<=0.3) SDSS (Sloan Digital Sky Survey) quasars, covered by the FIRST (Faint Images of the Radio Sky at Twenty Centimeters) and NVSS (NRAO VLA Sky Survey) radio surveys. Only 22 per cent are R_L_ with log(L_1.4GHz_)>=22.5W/Hz, the majority being compact (C), weak radio sources (WRS), with log(L_1.4GHz_)<24.5W/Hz. 15 per cent of the RL quasars have extended radio morphologies: 3 per cent have a core and a jet (J), 2 per cent have a core with one lobe (L), and 10 per cent have a core with two lobes (T), the majority being powerful radio sources (PRS), with log(L_1.4GHz_)>=24.5W/Hz. In general, RL quasars have higher bolometric luminosities and ionization powers than radio-quiet (RQ) quasars. The WRS have comparable black hole (BH) masses as the RQ quasars, but higher accretion rates or radiative efficiencies. The PRS have higher BH masses than the WRS, but comparable accretion rates or radiative efficiencies. The WRS also have higher FWHM_{[OIII]} than the PRS, consistent with a coupling of the spectral characteristics of the quasars with their radio morphologies. Inspecting the SDSS images and applying a neighbour search algorithm reveal no difference between the RQ and RL quasars of their host galaxies, environments, and interaction. Our results prompt the conjecture that the phenomenon that sparks the RL phase in quasars is transient, intrinsic to the active galactic nuclei, and stochastic, due to the chaotic nature of the accretion process of matter on to the BHs.
1503. Radio sources in the 6dFGS
ID:
ivo://CDS.VizieR/J/MNRAS/375/931
Title:
Radio sources in the 6dFGS
Short Name:
J/MNRAS/375/931
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have identified 7824 radio sources from the 1.4GHz NRAO VLA Sky Survey (NVSS, Cat. <VIII/65>) with galaxies brighter than K=12.75mag in the Second Incremental Data Release of the 6 degree Field Galaxy Survey (6dFGS DR2, Cat. <VII/249>). The resulting sample of redshifts and optical spectra for radio sources over an effective sky area of 7076deg^2^ (about 17 per cent of the celestial sphere) is the largest of its kind ever obtained. NVSS radio sources associated with galaxies in the 6dFGS span a redshift range 0.003<z<0.3 and have median z{bar}=0.043. Through visual examination of 6dF spectra we have identified the dominant mechanism for radio emission from each galaxy. 60 per cent are fuelled by star formation and 40 per cent are fuelled by an active galactic nucleus (AGN) powered by a supermassive black hole. We have accurately determined the local radio luminosity function (RLF) at 1.4GHz for both classes of radio source and have found it to agree well with other recent determinations. From the RLF of star-forming galaxies we derive a local star formation density of 0.022+/-0.001M_{sun}_/yr/Mpc^3^, in broad agreement with recent determinations at radio and other wavelengths.
1504. Radio survey of the 1H XMM/Chandra field
ID:
ivo://CDS.VizieR/J/MNRAS/378/995
Title:
Radio survey of the 1H XMM/Chandra field
Short Name:
J/MNRAS/378/995
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a deep 610-MHz survey of the 1^H^ XMM-Newton/Chandra survey area with the Giant Metre-wave Radio Telescope. The resulting maps have a resolution of ~7arcsec and an rms noise limit of 60Jy. To a 5{sigma} detection limit of 300Jy, we detect 223 sources within a survey area of 64arcmin in diameter. We compute the 610-MHz source counts and compare them to those measured at other radio wavelengths.
1505. Radio Survey of 7 X-ray Clusters of Galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/391/297
Title:
Radio Survey of 7 X-ray Clusters of Galaxies
Short Name:
J/MNRAS/391/297
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Australia Telescope Compact Array (ATCA) has been used at 1.38 and 2.38GHz to survey seven southern Abell clusters of galaxies with high X-ray luminosities: A2746, A2837, A3126, A3216, A3230, A3827 and A3836. The clusters have also been surveyed at 0.843GHz with the Molonglo Observatory Synthesis Telescope (MOST). We have listed a complete 1.38-GHz sample of 149 radio sources within the Abell circles centred on their X-ray centroids. We compare their identification fractions, emitted 1.38-GHz and optical powers, radio spectral indices and radial variation in projected source density with those of the radio-selected samples of Slee et al. (1998AuJPh..51..971S). We compare our fractional radio luminosity function with that of the radio-selected samples of Ledlow and Owen (1996AJ....112....9L) and Slee et al. (1998AuJPh..51..971S). Three significant differences are noted between X-ray and radio-selected samples of clusters; (1) the X-ray sample has an excess of flat-spectrum radio sources; (2) the fractional radio luminosity function for the FR I sources in the X-ray selected sample is much steeper, implying that fewer of their cluster galaxies become hosts for the stronger FR I radio galaxies; (3) a complete absence of FR II radio galaxies in the X-ray selected sample. The average excess projected density of radio sources near our cluster centres is approx. 5 times the background source density.
1506. RASS-6dFGS catalogue
ID:
ivo://CDS.VizieR/J/MNRAS/401/1151
Title:
RASS-6dFGS catalogue
Short Name:
J/MNRAS/401/1151
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalogue of 3405 X-ray sources from the ROSAT All Sky Survey (RASS) Bright Source Catalogue which fall within the area covered by the 6dF Galaxy Survey (6dFGS). The catalogue is count-rate limited at 0.05cts/s in the X-ray and covers the area of sky with {delta}<0{deg} and |b|>10{deg}. The RASS-6dFGS sample was one of the additional target catalogues of the 6dFGS and as a result we obtained optical spectra for 2224 (65 per cent) RASS sources. Of these, 1715 (77 per cent) have reliable redshifts with a median redshift of z=0.16 (excluding the Galactic sources). For the optically bright sources (b_J_<=17.5) in the observed sample, over 90 per cent have reliable redshifts. The catalogue mainly comprises quasi-stellar objects (QSOs) and active galaxies but also includes 238 Galactic sources. Of the sources with reliable redshifts the majority are type 1 active galactic nuclei (AGN, 69 per cent), while 12 per cent are type 2 AGN, 6 per cent absorption-line galaxies and 13 per cent are stars. We also identify a small number of optically faint, very low redshift, compact objects which fall outside the general trend in the b_J_-z plane. The RASS-6dFGS catalogue complements a number of Northern hemisphere samples, particularly the ROSAT Bright Source Catalogue-NRAO VLA Sky Survey (RBSC-NVSS) sample (Bauer et al., 2000, Cat. J/ApJS/129/547/), and furthermore, in the same region of sky (-40{deg}<{delta}<0{deg}) reveals an additional 561 sources that were not identified as part of that sample. We detect 918 sources (27 per cent) of the RASS-6dFGS sample in the radio using either the 1.4GHz NVSS or the 843MHz Sydney University Molonglo Sky Survey (SUMSS) catalogues and find that the detection rate changes with redshift. At redshifts larger than 1 virtually all of these sources have radio counterparts and with a median flux density of 1.15Jy, they are much stronger than the median flux density of 28.6mJy for the full sample. We attribute this to the fact that the X-ray flux of these objects is being boosted by a jet component, possibly Doppler boosted, that is only present in radio-loud AGN. The RASS-6dFGS sample provides a large set of homogeneous optical spectra ideal for future studies of X-ray emitting AGN.
1507. RATAN COLD Reined (RCR) catalogue
ID:
ivo://CDS.VizieR/J/other/AstBu/72.150
Title:
RATAN COLD Reined (RCR) catalogue
Short Name:
J/other/AstBu/72
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the additional list of radio sources of the RCR (RATAN Cold Refined) catalog. The sources was obtained on the observation data of the COLD experiment which included a series of surveys carried out in 1980-1999 on the RATAN-600 radio telescope. This part of RCR catalogue contains the right ascensions, integrated flux densities at 7.6cm (3.94GHz) and their spectral indices 3.94 and 0.5GHz of 269 objects detected in the right-ascension interval 2h<R.A.<7h and also additional 24 radio sources found in only one survey and 3 transient candidates in the right-ascension interval 2h<R.A.<17h. We constructed radio spectra of the sources using data of the catalogues from CATS and VizieR databases which the strip of COLD surveys overlays, and, in cases of weak sources, for this purpose we used the flux density values estimated from VLSSr, GLEAM, TGSS, and GB6 survey maps. 6% of the sources, which are mostly weaker than 30 mJy at 3.94GHz, have flux density data only at two frequencies - 1.4 and 3.94GHz. About 30% of these sources have flat or inverse spectra (alpha>-0.5) at 3.94GHz. We verified the reliability of identifications of the sources detected in the scans by comparing the coordinates and integrated flux densities with the corresponding parameters of the sources of the NVSS catalogue. In the central 10'-part of the strip at 10mJy level completness of the catalogue is about 90% and we found no objects that lack in decimeter-wave catalogues.
1508. RATAN-600 Zenith-Field sky survey (RZF) catalog
ID:
ivo://CDS.VizieR/J/AZh/84/227
Title:
RATAN-600 Zenith-Field sky survey (RZF) catalog
Short Name:
J/AZh/84/227
Date:
21 Oct 2021
Publisher:
CDS
Description:
A catalog of radio sources detected in a deep RATAN-600 survey is presented. The catalog was obtained in the region 0h<=RA(2000.0)<=24h, Dec(2000.0)=41:30:42+/-2, at the declination of the bright radio source 3C 84. There were nine sessions of multi-wavelength observations at wavelengths lambda=1-55cm, and more than 300 daily scans were accumulated at each wavelength. This is the first stage in the reduction of an extensive database accumulated by the Cosmological Gene Project. The RATAN-600 Zenith Field (RZF) catalog was obtained at the central wavelength of 7.6cm, and contains 437 radio sources, virtually all of which have been identified with NVSS objects. Most of the flux densities for the catalog sources are above the 5 level. Noise from faint (mainly new) background sources at a level of about 0.8mJy has been detected. The minimum flux density of the catalog, 2.5mJy, is comparable to the flux-density limit of the NVSS catalog. The catalog is more than 80% complete for sources with flux densities >3mJy.
1509. RAVE double-lined spectroscopic binaries
ID:
ivo://CDS.VizieR/J/AJ/140/184
Title:
RAVE double-lined spectroscopic binaries
Short Name:
J/AJ/140/184
Date:
21 Oct 2021
Publisher:
CDS
Description:
We devise a new method for the detection of double-lined binary stars in a sample of the Radial Velocity Experiment (RAVE) survey spectra. The method is both tested against extensive simulations based on synthetic spectra and compared to direct visual inspection of all RAVE spectra. It is based on the properties and shape of the cross-correlation function, and is able to recover ~80% of all binaries with an orbital period of order 1 day. Systems with periods up to 1 yr are still within the detection reach. We have applied the method to 25,850 spectra of the RAVE second data release and found 123 double-lined binary candidates, only eight of which are already marked as binaries in the SIMBAD database. Among the candidates, there are seven that show spectral features consistent with the RS CVn type (solar type with active chromosphere) and seven that might be of W UMa type (over-contact binaries). One star, HD 101167, seems to be a triple system composed of three nearly identical G-type dwarfs. The tested classification method could also be applicable to the data of the upcoming Gaia mission.
1510. RAVE DR5 Cone Search
ID:
ivo://org.gavo.dc/rave/q/cone
Title:
RAVE DR5 Cone Search
Short Name:
rave_scs
Date:
27 Dec 2024 08:31:12
Publisher:
The GAVO DC team
Description:
The RAdial Velocity Experiment (RAVE) contains stellar atmospheric parameters (effective temperature, surface gravity, overall metallicity), radial velocities, chemical abundances and distances. Observations between 2003 and 2013 were used to build the five RAVE data releases.

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