Аннотация:New combined opto – acoustical gravitational antenna (OGRAN) is installed in the
underground lab of Baksan Neutrino Observatory INR RAS. The designed sensitivity at the level of
10^-19 in term of metric perturbation was realized successfully. It is enough for a registering of short GW signals from relativistic events type of SN explosion and other asymmetrical star collapses in
our Galaxy and close environment with radius 100 Kpc. To expend the frequency reception band
of this resonance antenna some modernization associated with Hi-Tech mirrors was carried out.
Mirrors of high reflectivity and very small losses were installed in both FP cavities of the setup. It
resulted in increased finesse of cavities up to 25 thousand and the corresponded value of transfer
function in two order of value. Expected reception frequency band has to consist 30–40 Hz around
the resonance frequency 1.3 KHz. However for to check it experimentally one need to change main
characteristics of feed back circuits adapted to increased transform factor of the modernized setup.
These works are planned to be finished in a few months of current year. At the end of the year
the new gravitational detector has to be put in operation regime of monitoring collapses in multi
channel detection with Baksan Underground Neutrino Scintillate Telescope (BUST).