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We developed an algorithm to search automatically for LSB galaxies in the DPOSS plate scans. The algorithm consists of three different steps in which: i) the original image is processed with a standard image analysis package (e.g. SExtractor) and normal high surface brightness objects are removed; ii) a series of filters with an exponential compensated profile are applied at different scales; iii) significance maps are pruned by selecting, for each detection, the characteristic scale and significance; iv) candidates are then trimmed by measuring them on the original image with a fit with an exponential profile. Multicolor optical follow-up with CCD has begun on some of the best candidates. [ABSTRACT FROM AUTHOR]

We describe the telescope concept of the VST - the VLT survey telescope - and the scientific and instrumental background which lead to the kick-off of the project for the realization of a 2.6 m telescope for wide field to be placed at Paranal, on the VLT plateau within the year 2001. The project for the camera and the data handling and archiving, plus the analysis pipeline are outlined, with particular emphasis on the possible scientific surveys and stand alone projects. We will briefly review some of the scientific projects for which the VST was conceived, and its impact on the VLT science. [ABSTRACT FROM AUTHOR]

We study here the visibility function of emission lines expected for GOHSS. This spectrograph will accomplish, on spectra observed at resolution 4000, OH night -sky suppression by mean of a software subtraction. In this way only a small fraction of pixels is lost because of atmospheric OH contamination. Moreover, for strong emission lines, (i.e. redshifted $H\alpha$), where OH lines are strong it is possible by a weighted fit to recover part of the lost flux of the target object. Taking into account the expected noise sources and the instrument eciency we find that lines with a flux limit of $\gtrsim 5 10^{-17}$ erg cm-2s -1 can be detected in 2 hrs with $S/N \backsimeq 3$. [ABSTRACT FROM AUTHOR]

The Principal Component Analysis (PCA), allows to describe a spectrum with few physical significative parameters and it has demonstrated to be a powerful tool in order to classify galaxy spectra. Here we present a method capable to extend this technique to the case of unfluxed data, which also deels with the problem of having different spectral coverage in restframe wavelength range (typical in the case of redshift surveys spectra). Despite an increase of the computational burden we are able, for $m_{B_{j}} \!=\! 19.5$ galaxies, to both classify the unfluxed spectra and to extrapolate them to derive k-corrections from the spectra themselves with reasonable uncertainty. [ABSTRACT FROM AUTHOR]