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J/AJ/110/880                           Radio reference frame (Johnston+ 1995)

A radio reference frame Johnston K.J., Fey A.L., Zacharias N., Russell J.L., Ma C., de Vegt C., Reynolds J.E., Jauncey D.L., Archinal B.A., Carter M. S., Corbin T.E., Eubanks M.T., Florkowski D.R., Hall D.M., McCarthy D.D., McCulloch P.M., King E.A., Nicolson G., Shaffer D.B. <Astron. J. 110, 880 (1995)> =1995AJ....110..880J
ADC_Keywords: Radio sources ; Positional data ; VLBI Abstract: A catalogue is presented based on the radio positions of 436 extragalactic sources distributed over the entire sky. The positional accuracy of the sources is better than 3 milliarcsec (mas) in both coordinates, with the majority of the sources having errors better than 1mas. This catalogue is based upon a general solution of all applicable dual frequency 2.3 and 8.4GHz Mark-III VLBI data available through the end of 1993 consisting of 1,015,292 pairs of group delay and phase delay rate observations. Details and positions are also given for an additional 124 objects that either need further observation or are currently unsuitable for the definition of a reference frame. The final orientation of the catalogue has been obtained by a rotation of the positions into the system of the International Earth Rotation Service and is consistent with the FK5 J2000.0 optical system, within the limits of the link accuracy. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table4.dat 136 436 Radio positions of sources used to define the reference frame table5.dat 136 124 Radio positions of candidate and other sources table6.dat 51 53 Sources observed unsuccessfully table9.dat 144 613 Supplementary source identification
See also: I/251 : VLBI International Celestial Reference Frame (ICRF) (Ma+, 1997) J/ApJS/128/17 : VLBA obs. of radio reference frame sources. III. (Fey+, 2000) Byte-by-byte Description of file: table4.dat table5.dat
Bytes Format Units Label Explanations
3 I1 --- Class Source Classification (1) 13- 20 A8 --- IERS Source Name 28- 29 I2 h RAh Right ascension (J2000) 31- 32 I2 min RAm Right ascension (J2000) 37- 45 F9.6 s RAs Right ascension (J2000) 50- 57 F8.6 s e_RAs Right ascension (J2000) Formal Error (2) 62 A1 --- DE- Declination sign 64- 65 I2 deg DEd Declination (J2000) 67- 68 I2 arcmin DEm Declination (J2000) 73- 80 F8.5 arcsec DEs Declination (J2000) 85- 91 F7.5 arcsec e_DEs Declination (J2000) Formal Error (2) 95-100 F6.3 yr Epoch-1900 Mean Epoch of Observation (Epoch-1900) 104-109 F6.3 yr EpF-1900 Epoch of First Observation (Epoch-1900) 113-118 F6.3 yr EpL-1900 Epoch of Last Observation (Epoch-1900) 123-127 I5 --- EpNexp Number of experiments in which a source was observed 132-136 I5 --- Nobs Number of delay/rate observations used in solution
Note (1): 1,2-defining; 3-candidate; 4,5-other; 6-not detected Note (2): The formal errors refer to a position based on all observations of a source, which is different from the level of accuracy expected from only one observation or experiment. Systematic errors are estimated to be at the 0.5mas level. The right ascension formal error for 0420-014 was taken from the CTF solution because the right ascension of this source was fixed in the ICF solution to its a priori value in order to define the equinox. Consequently, the right ascension uncertainty of 0420-014 should be added in quadrature to the right ascension uncertainties of the remaining sources.
Byte-by-byte Description of file: table6.dat
Bytes Format Units Label Explanations
3 I1 --- Class Source Classification (1) 13- 20 A8 --- IERS Source Name 28- 29 I2 h RAh Right ascension (J2000) 31- 32 I2 min RAm Right ascension (J2000) 34- 37 F4.1 s RAs Right ascension (J2000) 42 A1 --- DE- Declination sign 44- 45 I2 deg DEd Declination (J2000) 47- 48 I2 arcmin DEm Declination (J2000) 50- 51 I2 arcsec DEs Declination (J2000)
Note (1): 1,2-defining; 3-candidate; 4,5-other; 6-not detected
Byte-by-byte Description of file: table9.dat
Bytes Format Units Label Explanations
1- 8 A8 --- IERS Source name 12- 14 A3 --- Type Optical identification (1) 18- 22 F5.3 --- z ? Redshift 26- 30 F5.2 mag mv ? Visual Magnitude 34- 37 F4.1 Jy S6cm ? 6cm (5GHz) Radio flux density 49- 72 A24 --- Alt Alternate name(s) 74- 92 A19 --- BibCode Reference in standard coded form 95-144 A50 --- Text Authors and Reference
Note (1): QSO = quasar, BSO = blue stellar object, GAL = galaxy, LAC = BL Lac object, EF = empty field
Origin: AAS CD-ROM series, Volume 5, 1995 Lee Brotzman [ADS] 27-Sep-1995 History: * 10-Jan-1996; first archive * 06-Nov-2000: Added bibcodes in table9.dat (F. Ochsenbein, CDS)
(End) [CDS] 10-Jan-1996
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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