Strong gravitational lensing of gravitational waves from double compact
  binaries - perspectives for the Einstein Telescope
  Gravitational wave (GW) experiments are entering their advanced stage which
should soon open a new observational window on the Universe. Looking into this
future, the Einstein Telescope (ET) was designed to have a fantastic
sensitivity improving significantly over the advanced GW detectors. One of the
most important astrophysical GW sources supposed to be detected by the ET in
large numbers are double compact objects (DCO) and some of such events should
be gravitationally lensed by intervening galaxies.
  We explore the prospects of observing gravitationally lensed inspiral DCO
events in the ET. This analysis is a significant extension of our previous
paper. We are using the intrinsic merger rates of the whole class of DCO
(NS-NS,BH-NS,BH-BH)located at different redshifts as calculated by Dominik et
al. by using {\tt StarTrack} population synthesis evolutionary code. We discuss
in details predictions from each evolutionary scenario. Our general conclusion
is that ET would register about $50-100$ strongly lensed inspiral events per
year. Only the scenario in which nascent BHs receive strong kick gives the
predictions of a few events per year. Such lensed events would be dominated by
the BH-BH merging binary systems. Our results suggest that during a few years
of successful operation ET will provide a considerable catalog of strongly
lensed events.
