RTV9C15GHZ ivo://nasa.heasarc/rtv9c15ghz NASA/GSFC HEASARC Waldram et al. 2026-10-09 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source The fields chosen for the first observations of the cosmic microwave background (CMB) with the Very Small Array (VSA) have been surveyed with the Ryle Telescope at 15 GHz. The authors have covered three regions around RA = 00<sup>h</sup>20<sup>m</sup> and Dec = +30<sup>o</sup>, RA = 09<sup>h</sup>40m and Dec = +32<sup>o</sup> and RA = 15<sup>h</sup>40<sup>m</sup> and Dec = +43<sup>o</sup> (J2000.0), comprising an area of 520 deg<sup>2</sup>. There are 465 sources in this entire area which are above the estimated completeness limit of ~ 25 mJy, although a total of ~ 760 sources were detected, some as faint as 10 mJy. The prime motivation of this study was to define a catalog of the foreground sources that must be monitored by the VSA during its observations at 34 GHz. In particular, it provides a means of identifying GigaHertz peaked spectrum (GPS) sources, which are important for the study of radio source evolution, as well as being a significant foreground for CMB observations over a range of wavelengths. Since this will be a new and quite extensive survey, it was desgignated as '9C' or the Ninth Cambridge survey. For the purpose of this particular component of the 9C survey, the authors designated as a subset, 3 circular areas, VSA1, VSA2 and VSA3, defined by the properties listed in Table 2 of the reference paper and reproduced below: <pre> Field Centre J2000.0 Center B1950.0 Radius Area RA Dec RA Dec (degrees) (sq. degrees) VSA1 00 17 36.5 +30 16 39 00 15 00.0 +30 00 00 5.5 95.0 VSA2 09 40 57.7 +31 46 21 09 38 00.0 +32 00 00 6.0 113.0 VSA3 15 36 42.7 +43 20 11 15 35 00.0 +43 30 00 5.0 78.5 </pre> There are 242 sources which were both above the 25 mJy completeness limit and were in the 286.5 deg<sup>2</sup> contained within these 3 circular fields. These source were listed in 3 tables in the reference paper, Table 4 (VSA1), Table 5 (VSA2) and Table 6 (VSA3). These have been combined into this one HEASARC table, in which the HEASARC added a new parameter vsa_field, which is set to 1 for the VSA1 sources, 2 for the VSA2 sources, and 3 for the VSA3 sources. This table was created in November 2010 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/342/915">CDS catalog J/MNRAS/342/915</a> files table4.dat, table5.dat and table6.dat. This is a service provided by NASA HEASARC . 2003MNRAS.342..915W https://heasarc.gsfc.nasa.gov/W3Browse/all/rtv9c15ghz.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=rtv9c15ghz& GET text/xml 180 99999 true 4.16583333 25.17444444 0.0166666666666667 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=rtv9c15ghz GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_rtv9c15ghz&Action=More+Options&Action=Parameter+Search&ConeAdd=1 RADIO CATALOG 0.0166666666666667 Radio public rtv9c15ghz 9C 15-GHz Ryle Telescope Survey of VSA Fields Source Catalog name Source Designation (9C JHHMM+DDMMa) meta.id;meta.main char nullable ra Right Ascension degree pos.eq.ra;meta.main double nullable dec Declination degree pos.eq.dec;meta.main double nullable flux_2_cm Flux Density at 15 GHz (2 cm) mJy phot.flux.density;em.radio.12-30GHz double nullable date_observed Observation Date mjd time.epoch;obs int nullable vsa_field VSA Field Number (Also Indicates Published Table/Sample Entry Originates from) meta.number;obs short nullable lii Galactic Longitude degree pos.galactic.lon double nullable bii Galactic Latitude degree pos.galactic.lat double nullable "__x_ra_dec" System unit vector column double nullable "__y_ra_dec" System unit vector column double nullable "__z_ra_dec" System unit vector column double nullable "__row" System index column char nullable