As already discussed in Sect. 4.2, two systematic effects are to be taken into account when dealing with ATESP flux densities, the clean bias and the bandwidth smearing effect.
Mosaic | cc's |
![]() ![]() |
RA range |
fld01to06 | 2033 | 78.7 | 22:32:35 - 22:39:24 |
fld05to11 | 1796 | 77.8 | 22:39:28 - 22:49:51 |
fld10to15 | 3104 | 88.1 | 22:49:54 - 22:56:46 |
fld20to25 | 2823 | 83.0 | 23:31:30 - 23:38:20 |
fld24to30 | 2716 | 82.8 | 23:38:27 - 23:48:51 |
fld29to35 | 2044 | 79.2 | 23:48:54 - 23:55:43 |
fld34to40 | 1616 | 76.3 | 23:55:51 - 00:06:15 |
fld39to45 | 2535 | 81.2 | 00:06:21 - 00:13:10 |
fld44to50 | 2377 | 78.0 | 00:13:20 - 00:23:35 |
fld49to55 | 2168 | 78.6 | 00:23:45 - 00:30:35 |
fld54to60 | 2504 | 77.3 | 00:30:40 - 00:41:01 |
fld59to65 | 2447 | 79.4 | 00:41:07 - 00:47:57 |
fld64to70 | 1899 | 75.1 | 00:48:03 - 00:58:29 |
fld69to75 | 3119 | 81.9 | 00:58:30 - 01:05:22 |
fld74to80 | 2558 | 77.1 | 01:05:26 - 01:15:50 |
fld79to84 | 1522 | 68.9 | 01:15:53 - 01:22:50 |
The flux densities reported in the ATESP source catalogue are not corrected
for such systematic effects. The corrected flux densities (
)
can be
computed as follows:
The clean bias correction is taken into account by the term in the square brackets. As discussed in Paper I, Sect. 5.3, the importance of the clean bias effect varies from mosaic to mosaic depending on the average number of clean components (cc's). In particular we derived the values for the parameters a and b in three different mosaics representing the case of low (fld34to40, 1616 cc's), intermediate (fld44to50, 2377 cc's) and high (fld69to75, 3119 cc's) average number of cc's (see Table 4 of Paper I).
In correcting the source fluxes for the clean bias, we suggest to set (a,b)=(0.09,0.85) whenever the mosaic average number of cc's is < 2000 (low-cc's case); (a,b)=(0.13,0.75) whenever the mosaic cc's average number is between 2000 and 3000 (intermediate-cc's case); (a,b)=(0.16,0.67) whenever the mosaic cc's average number exceeds 3000 (high-cc's case). The average number of clean components for each mosaic is reported in Table B1. In order to trace back the sources to the original mosaics, Table B1 lists also the right ascension range covered by each mosaic (indicated by the RA of the first and the last source in that mosaic).
The clean bias is a function of the source signal-to-noise ratio
.
Since the noise level is fairly uniform within each mosaic, it is possible
to assume
equal to the mosaic average noise value (
in
Table B1, we refer to Paper I for details on mosaic noise
analysis and average noise value definition).
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