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The observations are carried out by exicuting a sequence of alternating north- and south-bound declination scans across the galactic plane with two beams aligned at 11^o to the sky track. Since the declination scans are a fixed length (4.3^o in 1977-1979 and 4.0^o in 1980-1984) the galactic latitude coverage varies with the inclination of the galactic plane to the meridian, from +2.15^o at the northern extreme (DEC= 62^o) to +-1.2^o at DEC=0^o. Coverage of the observing region is achieved by interleaving 14 scan sequences. Short-term variability information is obtained by repeating a particular sequence five to six times during one observing session. The same sequences is repeated two to three timesd a year later to provide long-term variability information. In general, each region of sky has been repearted surveyed eight times with a northbound scan in one sequence and a further eight times with a southbound scan from another sequence, for a total of 16 repeats over 5 yr. ...
The analysis of the 1984 observations is incomplete and will not be discussed further in this paper. In three longitude intervals 40^o < l < 55^o, 87^o < l < 86^o and 111 <l < 114^o, the galactic confusion was too large to permit the detection of discrete sources. These regions are not included in the analysis presented here but will the subject of another paper describing a new analysis technique.
Column 1 gives the source name in the 8-digit "Parkes" system.
Columns 2-3 and 3-4 give source coorditanes 1950 with 1sigma errors.
The mean flux density and estimated 1sigma error are listed in columns 5-6.
Column 7 is size (diam) in arcmin in direction of the scan throgh the source.
Column 8-14 present the results of the search for variability.
Column 8 gives the number of observations of the source in that observing
epoch which exhibits the largest short-term variability. This was the epoch
used tio calculate the short-term variability indices, V1 and V2, which are
listed in colimn 9 and 10. The V1 index is the ratio of the measured rms
variation to the expected 1sigma variation due to the noise and instrumental
effects combined. For nonvariable sources, the index V1, by definition,
has an expectation value of one. This index is effective in detecting
variability that occurs continuously. However, for sources that vary only
a small fraction of the time, or when there are only two or three mesurements,
V1 will considerably underestimate the degree of variability.
To ovewcome this problem we calculate a second index, V2, which measures
the largest deviation from the mean signal strength, in units of the expected
1sigma variation (see Taylor & Gregory 1983).
Sources are classified as short-term variables if the probability of
occurrence, by chance, of the measured values of V1 and/or V2 is less than
0.1 %. Sources for which the probability of V1 and/or V2 is less than 1%,
but greater than 0.1% are classified as possible variables.
GTname RA_1950+-s DEC_1950+-" S4.79+-mJy size' M V_1 V_2 ? ? ? ? ? long_ind term_var ----+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1--- GT0001+625 000100 10 +623129 43 200 23 1.2 14 0.70 1.44 63.16 57.28 3.58 238.40 1.00 0.78 0 1