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VIII/84   A final non-redundant catalogue for 7C 151-MHz survey (Hales+ 2007)

A final non-redundant catalogue for the 7C 151-MHz survey Hales S.E.G., Riley J.M., Waldram E.M., Warner P.J., Baldwin J.E. <Mon. Not. R. Astron. Soc. 382, 1639 (2007)> =2007MNRAS.382.1639H
ADC_Keywords: Radio sources ; Surveys Keywords: catalogues - surveys - radio continuum: general Description: We present a final unified catalogue for the 7C survey at 151 MHz with resolution 70x70cosec(dec) arcsec2. This has been constructed by amalgamating the existing catalogues derived from individual fields imaged at this resolution and eliminating redundancy in regions of mutual overlap. This is a non-trivial procedure because the flux in multiple-component sources may be fitted differently on alternative images, owing, for example, to differences in local noise and beam distortion. The final catalogue thus produced contains 43683 sources. Separate final catalogues have been published for the 7C Galactic Plane survey (7CG, see Cat. J/MNRAS/294/607) and the lower-resolution survey of the low-declination strip 9h<RA<16h, 20deg<Dec<35deg (Cat. J/MNRAS/282/779). The individual catalogues for about 40 of the regions contributing to the total have already been published, together with full details of the methodology, in MNRAS or A&AS: Lacy et al. 1995, MNRAS, 276, 614 (=1995MNRAS.276..614L) (#92 below) Visser et al. 1995, A&AS, 110, 419 (=1995A&AS..110..419V) (#93 below) Pooley et al. 1998, MNRAS, 298, 637 (=1998MNRAS.298..637P) (#94-96 below) Riley et al. 1999, MNRAS, 306, 31 (=1999MNRAS.306...31R) (# 1-33 below) and these data are also available via the MRAO website at http://www.mrao.cam.ac.uk/surveys/7C/ Individual catalogues for the remaining 58 regions by Riley et al. (#34-91 below) were released electronically via the MRAO website in November 2001. These include a re-analysis of data originally published in rather a different parametrization by McGilchrist et al. 1990, MNRAS, 246, 110 (=1990MNRAS.246..110M) The regions re-analyzed are those numbered #41,44,59,60,62 and 63 below and they supersede McGilchrist's 1990 publication. The RAxDec coverage, average rms noise, flux density of the faintest source listed and completeness limit for each of the individual regions contributing to the final catalogue are given in the table "regions.dat". 1-sigma errors on the listed source positions may be approximated by: RA..error(arcsec) = SQRT(1.0**2 + (32/SNR)**2) Dec.error(arcsec) = Kcosec(dec) x (RA error) where (approx) K= 1.0 around dec 70, increasing to 1.3 below dec 50, and 1-sigma errors on the listed flux densities may be approximated by: Error on S beam-fitted(Jy) = SQRT(0.03**2 + SNR**-2) x S(Jy) Error on SINT(Jy) = 1.5 x SQRT(0.03**2 + SNR**-2) x SINT(Jy) where SNR, S and SINT correspond to the columns denoted by those names in the byte-by-byte description below. For multi-component sources the SNR for the brightest component is used to estimate the SINT error. For further details of the surveys and data analysis procedures please refer to the published papers referenced at the head of this file and references therein. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file 7c.dat 86 43683 7C sourcelist of 43683 sources regions.dat 52 96 List of fields observed
See also: J/MNRAS/282/779 : 7C: 151-MHz survey of region 9-16h 20-35deg (Waldram+ 1996) J/MNRAS/294/607 : 7C(G) 151MHz survey of the Galactic plane (Vessey+ 1998) Nomenclature Note: Sources of the 7C catalogue should be designated with their full B1950 beam-fitted position with 'format' 7C HHMMSS.s+DDMMSS, e.g. 7C 001920.0+451334 Byte-by-byte Description of file: 7c.dat
Bytes Format Units Label Explanations
1- 2 I2 h RAh Beam-fitted position right ascension B1950 4- 5 I2 min RAm Beam-fitted position right ascension B1950 7- 10 F4.1 s RAs Beam-fitted position right ascension B1950 12 A1 - DE- Beam-fitted position declination (sign) 13- 14 I2 deg DEd Beam-fitted position declination B1950 16- 17 I2 arcmin DEm Beam-fitted position declination B1950 19- 20 I2 arcsec DEs Beam-fitted position declination B1950 24- 25 I2 h RAIh Centroid position right ascension B1950 27- 28 I2 min RAIm Centroid position right ascension B1950 30- 33 F4.1 s RAIs Centroid position right ascension B1950 35 A1 - DEI- Centroid position declination (sign) 36- 37 I2 deg DEId Centroid position declination B1950 39- 40 I2 arcmin DEIm Centroid position declination B1950 42- 43 I2 arcsec DEIs Centroid position declination B1950 47- 52 F6.3 Jy S Beam-fitted flux density, in Jy/beam 54- 59 F6.3 Jy Sint Integrated flux density 61- 65 F5.1 --- SNR Signal-to-noise ratio 67- 70 F4.1 --- Extent Extent of the source in units of local beam area 74 I1 --- Nmax *Number of local maxima within the integrated region 76- 79 I4 --- ICOMP *Serial number identifying complex source (set to 0 if Nmax=1) 81- 86 I06 --- Map *Field from which data record originates
Note on Nmax and ICOMP: ICOMP is a serial number denoting a particular complex source - it has the same value for all the Nmax components (local maxima) which belong to that particular source, allowing the user to associate its individual components listed in the catalogue, no matter how the catalogue is ordered. Nmax specifies the total number of components. For a source with only one component Nmax=1 and ICOMP is set to 0 Note on Map: Field from which data record originates with + sign excluded, e.g. Map 072245 denotes the region 0722+45
Byte-by-byte Description of file: regions.dat
Bytes Format Units Label Explanations
1- 2 I2 --- Reg Region number 4- 9 I06 --- Map Name of map 11 A1 --- r_Map [*a-e] Origin of the region data (1) 14- 15 I2 h RA1.h Coverage RA1-RA2xDE1-DE2 B1950 (2) 17- 18 I2 min RA1.m Coverage RA1-RA2xDE1-DE2 B1950 (2) 20 A1 --- --- [-] 22- 23 I2 h RA2.h Coverage RA1-RA2xDE1-DE2 B1950 (2) 25- 26 I2 min RA2.m Coverage RA1-RA2xDE1-DE2 B1950 (2) 27 A1 --- DE1.- Coverage RA1-RA2xDE1-DE2 B1950 (2) 28- 29 I2 deg DE1.d Coverage RA1-RA2xDE1-DE2 B1950 (2) 31- 32 I2 arcmin DE1.m Coverage RA1-RA2xDE1-DE2 B1950 (2) 34 A1 --- --- [-] 35 A1 --- DE2.- Coverage RA1-RA2xDE1-DE2 B1950 (2) 36- 37 I2 deg DE2.d Coverage RA1-RA2xDE1-DE2 B1950 (2) 39- 40 I2 arcmin DE2.m Coverage RA1-RA2xDE1-DE2 B1950 (2) 43- 44 I2 mJy Noise Average rms noise before primary beam correction 46- 48 I3 mJy Sfaint Flux density of the faintest source listed 50- 52 I3 mJy Scomp Completeness limit
Note (1): Origin for the region data as follows: a = from Riley et al. 1999MNRAS.306...31R (1-33) b = from Riley et al. 2001: 58 regions at (34-91) www.mrao.cam.ac.uk/surveys/7C/ c = from Lacy et al. 1995MNRAS.276..614 (92) d = from Visser et al. 1995A&AS..110..419 - an amalgamation of seven pointings (93) e = from Pooley et al. 1998MNRAS.298..637 (94-96) * = 150056 corrupted replaced by 150060 (an amalgamation of data from unpublished regions 144060, 152060) Note (2): RA coverage is indicated by approx RA range at Dec of field centre. Dec coverage is indicated by approx Dec range at RA of field centre.
History: * 24-Jan-2008: a spurious negative value of Nmax in row 28028 of 7c.dat was corrected on 24-Jan-2008
(End) Sally Hales [MRAO] 25-Jan-2008
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

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