Opto acoustical gravitational bar detector with cryogenic mirrors

TL;DR

This paper discusses enhancing the sensitivity of the OGRAN gravitational wave detector by cooling its components to cryogenic temperatures, achieving a two-order sensitivity improvement and describing a modernized cryogenic design with experimental results.

Contribution

It introduces a cryogenic version of the OGRAN detector, demonstrating a significant sensitivity increase and providing a practical design and experimental validation.

Findings

Sensitivity improved by two orders at nitrogen temperature.

Successful testing of a cooled pilot model with cryogenic mirrors.

Maintained optical scheme at low temperatures.

Abstract

Enhancing of sensitivity of the opto-acoustical gravitational wave (GW) antenna OGRAN installed in the underground facilities of Baksan Neutrino Observatory is analyzed. Calculations are presented showing a sensitivity improving on two orders of value after a cooling the solid body acoustical part of the antenna to the nitrogen temperature. A possibility of keeping of the same optical scheme of the antenna at low temperature is discussed. Design of modernized construction for cryogenic version of the antenna OGRAN is described. Test experiments with cooled pilot model carrying cryogenic mirrors illuminated by the optical pump up to 0.5 W are presented.