Review of the ASTROVIRTEL Experience at the end of its Three Approved Cycles

ASTROVIRTEL has concluded its three-year life cycle. A review of the last two cycles is presented. The program selection process was instrumental in ensuring that the tools and methods developed for the successful PIs were general enough to be reused by a wider community of users of the ESO/ST-ECF archive. It will be here shown how such goal was achieved. The programs of the last two cycles will be described touching upon scientific and technical requirements, technical challenges (quite typical for any astronomical archive) technical and scientific achievements. The overall exercise of hosting scientific investigators with quite spread scientific interests has been very effective in revisiting and augmenting various ESO/ST-ECF archive functionalities and scientific products. Some of the developed tools and methods are already integral part of the ESO/ST-ECF archive, while some others are still being optimised before becoming operational. ASTROVIRTEL forced the developers to look into both the HST and ESO archives, each with its own peculiarities, and come up with solutions as general as possible. Furthermore, ASTROVIRTEL has also played an important role in the Virtual Observatory phase A study, particularly in the area of data centres inter-operability and scientific requirements.