Today, great observatories around the world, devote a substantial amount of observing time to sky surveys. The resulted images are inputs of source finder modules. These modules search for the target objects and provide us with source catalogues. We sought to quantify the ability of detection tools in recovering faint galaxies regularly encountered in deep surveys. Our approach was based on com...

We present a spectroscopic determination of the redshift second source in Jackpot gravitational lens system J0946+1006, for which only photometric estimate $z_{\rm phot}$ = 2.41$^{+0.04}_{-0.21}$ has previously been available. By visually inspecting an archival VLT X-Shooter observation, we located single emission line from H-band. Among possible options find that this is most likely to be [OII...