VIII/37 The Third Bologna Survey (B3) (Ficarra+ 1985)
Third Bologna Survey at 408 MHz
Ficarra A., Grueff G., Tomassetti G.
<Astron. Astrophys. Suppl. Ser. 59, 255 (1985)>
=1985A&AS...59..255F 1985A&AS...59..255F
ADC_Keywords: Radio sources ; Surveys
Keywords: radiotelescope - radiosources - catalogue
Description:
This catalogue contains the first section of a sky survey performed at
408MHz with the 'Northern Cross' Radiotelescope. It contains about
13.000 radiosources. Although sources down to about 70mJy were
measured, only sources brighter than 0.10Jy are retained in the
catalogue. According to our estimate of confusion errors, this
corresponds to a detection threshold of about 5σ. The list is
meant to include all the sources with a measured flux S>0.10Jy, in the
sky area included between the declinations +37°15' and +47°37',
epoch 1978.0. A number of zones however are affected by interferences,
malfunctions, etc. The principal one is centered about the radiosource
Cyg A, which is itself in the map, but not in the catalogue. The zone
between RA 19h30m to 20h30m is entirely lacking, due to strong
confusion. In the zone from 19h00m to 19h30m and from 20h30m to
21h00m, only sources brighter than 0.75Jy are listed, and to this
level the catalogue is espected to be complete. For detailed
discussion of the completeness of the catalogue see the original
publication cited above.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
b3.dat 48 13340 The Bologna Third Catalogue
--------------------------------------------------------------------------------
See also:
VIII/36 : The Second Bologna Servey (B2)
J/AJ/98/419 : Observed quantities from B3 sources
Byte-by-byte Description of file: b3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- B3 Source name, (IAU-style), eventually followed
by a multiplicity letter A, B...
12- 13 I2 h RAh Right Ascension (1950.0)
14- 15 I2 min RAm Right Ascension (1950.0)
16- 19 F4.1 s RAs [0/60] Right Ascension (1950.0)
20 A1 --- DE- [+] Declination sign
21- 22 I2 deg DEd Declination (1950.0)
23- 24 I2 arcmin DEm Declination (1950.0)
25- 26 I2 arcsec DEs Declination (1950.0)
29- 33 F5.2 Jy Flux The source total flux. In the large majority
of cases, this is practically equivalent to
the peak flux
35- 37 F3.1 --- Fit Goodness of the fitting algorithm, related to
the R.M.S. value of te residuals in the
fitting matrix
39- 42 I4 --- ACOD1 ? Four digit string indicating source
reliability (1)
44 A1 --- n_Diam [RD] If not blank the source were measured by
a double source algorithm.
R => resolved D => double
45- 48 F4.1 arcmin Diam ? If the source is double: the separation
--------------------------------------------------------------------------------
Note (1): An algorithm was devised by which every source was marked with a
four-digit number n1, n2, n3, n4 with each digit indicating a
separate reason for problems, as follows:
n1: a disturbing, strong source is present, very close in R.A., or
very close in DEC. The flux ratio R is indicated by n1 and is
n1 = R/10, truncated to the integer.
n2: if non-zero, it indicates that the source lies in the vertical
part of the cross-shaped area, and in the position of a grating
response in N-S. It thus indicates a larger chance for the
source to be spurious. The value itself is the rank of the
grating response (n2 = 5 means the grating closer to the source,
etc. down to n2 = 1)
n3: if non-zero it means that the source is very close to a very
strong source, although not in the cross-shaped area mentioned
above. A circular area is defined with radius r=2.8sqrt(R)pix;
n3 indicates how close the source is to the disturbing source,
in units of 1/r
n4: if n4 > 4, it indicates that the source lies within a disturbed
area with the following code:
5: solar interferences
6: sidelobes of Cyg A
7: supernova remnant G160.4+2.8 (Felli et al., 1977A&AS...27..181F 1977A&AS...27..181F)
8: supernova remnant G166.0+4.3 (Willis, 1973A&A....26..237W 1973A&A....26..237W)
9: man-made interferences
If n4 < 4, it indicates that n4 (and no more) disturbing sources
are present. In this case the previous digit refer to the
stronger disturbing source.
--------------------------------------------------------------------------------
Acknowledgements:
The file and the basic documentation were kindly provided by
Marzia Cannizzaro in September 1995.
(End) Patricia Bauer [CDS] 16-Sep-1997