The VLT observations of the HDF-S NICMOS field: photometric catalog and high redshift galaxy candidates

We present the deep UBVRI observations of the HDF-S NICMOS field obtained a s part of the Science Verification of the VLT Unit 1 telescope. The images have been used to construct object catalogs and to obtain photometric redsh ifts. The effective field of view is similar or equal to 70 x 70 arcsec(2), and the formal 5 sigma limiting magnitudes (in a 2 FWHM aperture) are 26.3 , 27.8, 27.5, 26.9, 25.2 in the U, B, V, R and I bands, respectively. Thank s to the sub-arcsecond image quality, relatively long exposure time, and la rge collecting area of the VLT, this is the deepest set of multicolor image s ever obtained from a,groundbased telescope. Galaxy counts have been derived independently in each band, and show no sig nificant departures from previous data from wider areas. A multicolor photo metric catalog of all the galaxies selected in the R band has also been obt ained and used to derive photometric redshifts for all galaxies with R less than or equal to 26.5, using also the J,H and K magnitudes from the NICMOS deep observations. A significant fraction (similar or equal to 28%)of the galaxies is placed at z greater than or equal to 2. Among them, six robust candidates are found at z greater than or equal to 2.5.