Access to Astronomical Catalogues

← Click to display the menu
VIII/85A   SPECFIND V2.0 Catalog of radio continuum spectra   (Vollmer+ 2009)

A method for determining radio continuum spectra, and its application to large surveys Vollmer B. <Astron. Astrophys. 511, 53 (2010)> =2010A&A...511A..53V
ADC_Keywords: Radio sources ; Galaxies, radio ; Radio continuum Keywords: astronomical data bases: miscellaneous - radio continuum: general Description: This is the second release of the SPECFIND catalogue. For the radio cross-identification we included 3.76 million sources from 105 VizieR radio catalogues. The SPECFIND V2.0 catalogue contains about 107000 physical objects with associated radio spectra. With an increase of 8% of available sources with respect to the first release, we could increase the number of radio objects by 60%. The results of the spectrum identification process are provided as a master table, where a spectrum is attached to each radio source. Due to the SPECFIND algorithm, different radio sources of the same physical object can have somewhat different slopes and zero-points. We also present radio sources from positional cross-identification only taking into account the source extent and the survey resolution (overlapping beams or extents). The source flux densities were not taken into account as it was done for the SPECFINDV2.0 catalogue. In this sense, it represents the waste basket of SPECFINDV2.0. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file spectra.dat 124 631736 The parameters of the radio spectra waste.dat 114 1497216 Source parameters based on positional cross-id beam.dat 90 115 Characterisation of catalogues in SPECFIND simbadz.dat 86 107488 Redshifts from Simbad database (November 2015)
See also: VIII/13 : A new catalog of 53522 4.85GHz sources (BWE) (Becker+ 1991) VIII/14 : 87GB Catalog of radio sources (Gregory et al., 1991) VIII/15 : Parkes Radio Sources Catalogue (PKS) (Wright+ 1990) VIII/16 : Molonglo Reference Catalogue of Radio Sources (MRC) (Large+ 1991) VIII/17 : The North 20cm Survey (WB) (White+ 1992) VIII/36 : The Second Bologna Survey (B2) (Colla+ 1970-1974) VIII/37 : The Third Bologna Survey (B3) (Ficarra+ 1985) VIII/38 : The Parkes-MIT-NRAO 4.85GHz (PMN) Surveys (Griffith+ 1993-1996) VIII/40 : GB6 catalog of radio sources (Gregory+ 1996) VIII/42 : Texas Survey of radio sources at 365MHz (TXS) (Douglas+ 1996) VIII/44 : Miyun 232MHz survey (MIYUN) (Zhang+ 1997) VIII/52 : The MIT-Green Bank 5GHz Survey (Bennett+, 1986-91) VIII/60 : Interferometer phase calibration sources (JVAS) (Patnaik+ 1998) VIII/62 : The Westerbork Northern Sky Survey (WENSS) (Leiden, 1998) VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998) VIII/69 : The WISH catalogue at 352 MHz (de Breuck+ 2002) VIII/70 : Sydney University Molonglo Sky Survey (SUMSS) (Mauch+ 2003) VIII/71 : The FIRST Survey Catalog, Version 03Apr11 (Becker+ 2003) J/A+AS/85/805 : 11cm radio continuum survey. IV. (F3R) (Fuerst+ 1990) Byte-by-byte Description of file: spectra.dat
Bytes Format Units Label Explanations
1- 6 I6 --- Seq [1,107498] Sequential number of the spectrum (1) 8- 38 A31 --- Name Main name of the radio source (G1) 40- 41 I2 --- N [2,31] Number of points in spectrum 43- 48 F6.2 --- a Slope of spectrum (3) 50- 55 F6.2 [mJy] b Abscissa of spectrum (3) 57- 61 I5 MHz nu [30,15000] Frequency 63- 71 E9.3 mJy S(nu) Flux density at frequency nu 73- 80 E8.2 mJy e_S(nu) Mean error on S(nu) 82- 89 F8.4 deg RAdeg Right ascension (J2000) of source 91- 98 F8.4 deg DEdeg Declination (J2000) of source 100-108 E9.3 mJy dFlux Difference with flux expected from NVSS 110-116 F7.1 arcsec dRA Offset in RA from NVSS source 118-124 F7.1 arcsec dDE Offset in DE from NVSS source
Note (1): This number relates the sources that contribute to a single spectrum, i.e. there are N radio sources sharing the same Seq number. The number of independent spectra is 107498. Note (3): The coefficients of a and b of the flux density parametrization log(S(ν)) = a.log(ν) + b where the log is decimal (log10), S expressed in mJy and ν in MHz. Thus b represents log(S(1MHz)/1mJy).
Byte-by-byte Description of file: waste.dat
Bytes Format Units Label Explanations
1- 31 A31 --- Assoc Main name of the radio association (G1) 32- 38 I7 --- Seq [-272182,107498] Spectrum Sequential number (1) 40- 45 I6 MHz nu [30,15000] Frequency 47- 55 E9.3 mJy S(nu) Flux density at frequency nu 57- 64 E8.2 mJy e_S(nu) Mean error on S(nu) 66- 73 F8.4 deg RAdeg Right ascension (J2000) of source 75- 82 F8.4 deg DEdeg Declination (J2000) of source 84-114 A31 --- Name Name of the associated radio source (G1)
Note (1): when positive, the radio flux matches a spectrum and is therefore also included in the "spectra.dat" file; when negative, the flux does not match a spectrum.
Byte-by-byte Description of file: beam.dat
Bytes Format Units Label Explanations
1- 11 A11 --- Name Catalog abbreviation used in SPECFIND (G1) 13 A1 --- I [IS-] interferometer or Single dish 16- 20 I5 MHz nu [30,15000] Frequency 21- 22 A2 --- --- [. ] 24- 30 F7.4 arcmin beam Beam size 32- 37 F6.1 mJy Smin ? Sensitivity limit 39- 45 I7 --- N Number of sources in catalog 47- 50 F4.1 % sp ? Percentage of sources having a spectrum 52- 70 A19 --- BibCode Reference's bibcode 72- 90 A19 --- Cat Catalog acronyms in VizieR
Byte-by-byte Description of file: simbadz.dat
Bytes Format Units Label Explanations
1- 6 I6 --- Seq [1/107498] 8- 35 A28 --- SName Simbad name 37- 52 A16 --- SType Simbad object type 54- 63 F10.7 --- z ? Simbad redshift 65- 77 A13 --- n_z Simbad nature redshift 79- 86 F8.6 --- e_z ? rms uncertainty on z
Global Notes: Note (G1): a summary of the acronyms used, with indication of interferometric or single dish instrumentation, frequency, resolution, sensitivity limit (mJy), number of sources, percentage of sources with identified spectrum, and the identification of the catalog in the CDS collection is given as file "beam.dat". To distinguish sources of the same survey observed at different frequencies, we added a lowercase letter to the source acronym (e.g. FORa, FORb).
History: * 27-Jan-2009: First version, with 551852 records (66985 spectra) * 06-Jul-2009: Second version (A), with addition of "waste.dat" file * 04-Dec-2015: File simbadz.dat added
(End) Bernd Vollmer, Francois Ochsenbein [CDS] 06-Jul-2009
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

catalogue service

© Unistra/CNRS