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1970A&AS...1..281Colla
1972A&AS...7...11Colla
1973A&AS..11..291Colla
1974A&AS..18..147Fanti
See also Bologna 3
Bologna Sky Survey at 408 MHz (B2) (Dec = 21d40' to 40d18')
Description
This catalogue contains 9929 radio sources from the four parts of the
B2 sky survey performed with the Bologna 'Northern Cross' Radiotelescope.
The telescope's working frequency is 408 MHz and the resolving power is
3' in right ascension and 10' in declination. The limiting flux density
varies for the four parts, the survey is complete down to 0.2 Jy for
declinations between 29 and 34 degrees; it is complete down to 0.25 Jy
for declinations between 24 and 29.5 degrees, and between 34 and 40
degrees; and it is complete down to 0.6 Jy between declinations of
21.7 and 24 degrees. These data were originally published
in four papers: Colla et al. (1970), Colla et al. (1971), Colla, et al.
(1972), and Fanti et al. (1974).
2 name B2 name of source (char8, ex: '0512+24A')
1 cat Part of B2 catalog which contained the source (char4, example: 'B2.1')
3 dec_1950 radians Declination of source in radians (B1950) (real, example: 0.474555)
4 ra_1950 radians Right ascension of source in radians (B1950) (real, example: 5.125028)
5 dec_1950_deg degrees Declination of source in degrees (B1950) (real, example: 27.190001)
6 ra_1950_deg degrees Right ascension of source in degrees (B1950) (real, example: 293.642487)
7 flux Jy Flux density at 408 MHz (real, example: 0.277)
8 ref Reference to 3C or 4C catalog containing source (char2, example: '4C')
1. COLUMNS name cat
The name column gives the shortened B2 name of the source, obtained
by combining the hours and minutes of right ascension with the degrees
of declination. If necessary, a letter is added at the end to
distinguish between sources with similar positions. For example,
sources at 00h 24m 16.5s, 32d 43.7' and 00h 24d 29.4s, 32d 29.6'
would be named 0024+32A and 0024+32B. Note that in the literature,
sources are typically referred to as 'B2 0024+32A'. The cat column
gives the part of the B2 catalog in which the source is contained.
Example (name) (char8): '0512+24A'
Example (cat) (char4): 'B2.1'
2. COLUMNS dec_1950 ra_1950 dec_1950_deg ra_1950_deg
The first two columns list the declination and right ascension of the
source (epoch 1950) in radians. The second two columns list the same
position in degrees. Positional errors vary with flux density and
declination; for part 1 of the catalog (B2.1), it is as follows:
Flux Density RA Error Dec error
(Jy) (arcsec) (arcsec)
-----------------------------------------
>1.00 4" 16"
0.70 5 22
0.40 9 34
0.25 10 40
0.20 12 60
For B2.2, it is as follows:
Flux Density RA Error Dec error
(Jy) (arcsec) (arcsec)
-----------------------------------------
>1.00 6" 24"
0.70 7 35
0.40 11 50
0.30 13 60
0.25 15 70
For B2.3, it is as follows:
Flux Density RA Error Dec error
(Jy) (arcsec) (arcsec)
-----------------------------------------
>1.00 6" 25"
0.70 7 35
0.40 10 50
0.30 13 60
0.25 15 70
For B2.4, it is as follows:
Flux Density RA Error Dec error
(Jy) (arcsec) (arcsec)
-----------------------------------------
>1.00 6" 25"
<1.00 10 40
Example (dec_1950) (real): 0.474555
Example (ra_1950) (real): 5.125028
Example (dec_1950_deg) (real): 27.190001
Example (ra_1950_deg) (real): 293.642487
Field List
3. COLUMN flux
This column gives the peak flux density in Jy. For each region of the
record corresponding to a source, nearby sources were maintained only if
they had a flux density larger than twice the side-lobe due to that source.
The flux-scale calibration used is the one suggested by Kellermann (1964).
Flux density errors vary with flux density; for part 1 of the catalog
(B2.1), it is as follows:
Flux Density Error in flux density
(Jy) (Jy)
-------------------------------------
>1.00 5%
0.70 0.05
0.40 0.05
0.25 0.05
0.20 0.05
For B2.2, it is as follows:
Flux Density Error in flux density
(Jy) (Jy)
random systematic
errors errors
-----------------------------------------
>1.00 +/-8% +0.00
0.70 +/-0.08 +0.00
0.40 +/-0.06 +0.012
0.30 +/-0.05 +0.020
0.25 +/-0.05 +0.025
For B2.3, it is as follows:
Flux Density Error in flux density
(Jy) (Jy)
random systematic
errors errors
-----------------------------------------
>1.00 +/-8% +0.00
0.70 +/-0.08 +0.00
0.40 +/-0.06 +0.010
0.30 +/-0.05 +0.016
0.25 +/-0.05 +0.020
For B2.4, it is as follows:
Flux Density Error in flux density
(Jy) (Jy)
-----------------------------------------
>1.0 +/-8%
<1.0 +/-0.08
Example (flux) (real): 0.277
4. COLUMN ref
This column gives the reference as to whether the source is contained
in the 3C or 4C catalog.
Example (ref) (char2): '4C'
References
Colla G., Fanti C., Fanti R., Ficarra A., Formiggini L., Gandolfi E.,
Grueff G., Lari C., Padrielli L., Roffi G., Tomasi P., Vigotti M.:
A CATALOGUE OF 3235 RADIO SOURCES AT 408 MHz. 1970, Astron. Astrophys.
Suppl. Ser., 1, 281.
Colla G., Fanti C., Fanti R., Ficarra A., Formiggini L., Gandolfi E., Lari C.,
Marano B., Padrielli L., Tomasi P.: THE B2 CATALOGUE OF RADIO SOURCES -
SECOND PART. 1972, Astron. Astrophys. Suppl. Ser., 7, 1.
Colla G., Fanti C., Fanti R., Ficarra A., Formiggini L., Gandolfi E., Gioia I.,
Lari C., Marano B., Padrielli L., Tomasi P.: THE B2 CATALOGUE OF RADIO SOURCES
- THIRD PART. 1973, Astron. Astrophys. Suppl. Ser., 11, 291.
Fanti C., Fanti R., Ficarra A., Padrielli L.: THE B2 CATALOGUE OF RADIO SOURCES
- FOURTH PART. 1974, Astron. Astrophys. Suppl. Ser., 18, 147.
Kellermann, K.I. 1964, A.J., 140, 969.
Additional Information
According to a finding by A.E.Wright (ATNF) the positions given for the B2.1
catalogue differ (by a few tens of seconds) from those given in the electronic
version distributed by R. and C.Fanti. The latter is in use in the ADS, DIRA2,
EINLINE, and COMRAD databases. Note that although Dixon's Master List is in
fact consistent with the printed publication, the ADS/DIRA/EINLINE/COMRAD
are not! However, according to R. and C.Fanti the latter (distributed)
version is the more reliable one, since some correction (better precession?)
was made after the publication. This seems to imply that what is in the
Dixon list was TYPED from the publication, not taken from the tape.
Note that the inconsistency is present only for the B2.1 objects and not the
other parts of B2. (L.Feretti, priv.comm., Sep. 1993)
Origin submitted by M. Nanni
Date 24-Sep-1992
Revised 09-Nov-1992
Columns 8
Rows 9929
For catalog content:
D. E. Harris, SAO; harris@cfa.harvard.edu (9/92)