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J/A+AS/99/545   The Miyun 232 MHz survey. I                  (Zhang+, 1993)

The Miyun 232 MHz survey. I. Fields centred at RA: 00h41m, Dec: 41°12' and RA: 07h00m, Dec: 35°00' Zhang X., Zhen Y., Chen H., Wang S. <Astron. Astrophys. Suppl. Ser. 99, 545 (1993)> =1993A&AS...99..545Z (SIMBAD/NED BibCode)
ADC_Keywords: Radio continuum ; Radio sources ; Surveys Keywords: radio sources - survey Description: This catalogue contains a new meter-wave survey of the sky region north of declination 30°, carried out with the Miyun 232 MHz SSSynthesis Radio Telescope (MSRT) at HPBW 3.8' x 3.8' cosec(dec). Results from two fields are presented here; the fields are 8 degrees on a side, centered at 0041+41.2 and 0700+35.0. The accuracy of flux determination is limited by background fluctuation which is about 30 mJy. The catalogue is complete for sources with flux greater than 0.25 Jy. The total number of sources listed in the catalogue is 687. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file miyun232.dat 68 687 Miyun 232 MHz Survey of Two Fields: 0041+41.2 and 0700+35.0
See also: J/A+AS/121/59 : Miyun 232MHz survey (Zhang+ 1997) J/other/AcApS/16.103 : Miyun 232 MHz survey. II. The main list (Zhang+ 1996) Byte-by-byte Description of file: miyun232.dat
Bytes Format Units Label Explanations
2- 11 A10 --- Name Name of source (1) 13- 14 I2 h RAh Right Ascension (B1950) (hour) (2) 16- 17 I2 min RAm Right Ascension (B1950) (min) 19- 22 F4.1 s RAs Right Ascension (B1950) (sec) 24 A1 --- DE- Declination sign (B1950) (2) 25- 26 I2 deg DEd Declination (B1950) (deg) 28- 29 I2 arcmin DEm Declination (B1950) (arcmin) 31- 34 F4.1 arcsec DEs Declination (B1950) (arcsec) 36- 40 F5.2 Jy S232p Peak flux density in Jy (3) 42- 46 F5.2 Jy S232i ? Integrated flux density (3) 48- 51 F4.2 Jy Bkgr Local background level around source (4) 53- 62 A10 --- GB87name Name from 1987 Green Bank Catalogue (5) 64- 68 F5.2 --- Sp+Index ? Estimated spectral index from 232-4850 MHz (6)
Note (1): This column gives the name of the source, comprised of the letters "MY" followed by the hours and minutes of right ascension, the sign of the declination, and the degrees, to the nearest tenth of a degree. Note (2): These columns give the B1950 position of the source, Errors in position were estimated in three ways and the resulting rms of position errors can be expressed as RA_err (arcsec) = 5" / S (Jy) Dec_err = RA_err * cosec(Dec) Note (3): These columns give the peak flux density and the integrated flux density of the source, in Jy. The flux density scale of Baars et al. (1977A&A....61...99B) has been used. Errors in flux density were also estimated by three different methods: (a) the Monte-Carlo method, which serves to estimate the degradation of position and flux accuracy by background noise; (b) method of direct comparison, ie, comparing the observed data with well-chosen references; and (c) experimental formulas. Monte Carlo experiments were used at four different levels, i.e. 0.7 Jy, 1.0 Jy, 1.5 Jy and 2.0 Jy. From the results, the uncertainty of flux density was found to be independent of the artificial sources. These results showed that about 60% of the sources had apparent flux densities within ±30 mJy of their "true" flux densities. Note (4): This column gives the local zero level (in Jy), i.e. the average background level near the source. Note (5): This column gives the source name from the 1987 Green Bank Catalogue (Gregory and Condon 1991ApJS...75.1011G) (Cat. VIII/14) in the same IAU-format as in column 1 of the present data table [note that the original 87GB does NOT present IAU-names and that truncation to a tenth of a degree might lead to non-unique names!]. Note (6): This column gives the estimated spectral index between 232 MHz and 4850 MHz. Alpha is defined in the sense S ∝ να.
History: Prepared from the tables available at the "ADS Catalogue Service" (CfA, Harvard-Smithsonian Center for Astrophysics, Cambrigde MA)
(End) Patricio Ortiz [CDS] 30-Mar-1999
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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