7 Description of the released catalogue

After the fluctuation calibration has been carried out, the data frames undergo a further 6-parameter linear fit (see Eq. (1)) using the Tycho 2 standards. This is done since the residuals have been reduced and a more accurate fit can be achieved.

The final catalogue consists of the averaged positions from the calibrated data frames. For the current version only a simple algorithm is used whereby any images within 2'' of each other are considered as the same source. However, considering that the average image size is larger than this, it is likely that this algorithm is sufficient.

The current release of the catalogue (version 1.0) covers the declination zone $-3^\circ<\delta<+3^\circ$. The data is available over the Internet where the format of the catalogue is described. The main part of the survey extends to $+30^\circ$ and further releases of the catalogue which will complete the coverage will be available in the future from the same location. An extension of the survey is planned, extending it to $+50^\circ$ in the North and $-15^\circ$in the South.