Preliminary results on the cryogenic payload for the 3rd generation g.w. interferometers

Thermal Noise is one of the limiting factor in the low and intermediate frequency range of the interferometric Gravitational Wave (GW) detectors. For beating this limit, a full scale last stage suspension (payload) prototype has been designed and built. Together with a mirror made of silicon, it has been cooled down at low temperature. Suspending the mirror from a cradle system, identical to that one used in the present VIRGO payload, the cooling strategy, the thermal behavior as well as the system mechanical response have been deeply studied. In this paper, the results obtained during the first cooling of the tested prototype are reported. © 2010 IOP Publishing Ltd.