ИСТИНА

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.