Researchers from the Moscow State University, the Nuclear Research Institute and the Laser Physics Institute are working on the optic-acoustic gravitational antenna ORGAN, which will register gravitation waves from neutron stars. The new system will become an alternative to the American LIGO interferometers.
"Our system is an alternative to the LIGO interferometers (which made it possible to register gravitation waves for the first time). It functions in a substantially different range, and so in this sense we are expanding our abilities to see and hear the Universe", - the official publication Science in Siberia cites the director of the Laser Physics Institute, Alexey Taychenachev.
The gravitation signal was registered by LIGO in the range of about 100 Hertz. The Russian detectors work in the range of 3 kilohertz. They are aimed at lighter stars, such as neutron ones.
The Russian detector is set up in the Baksan Neutrino Observatory of the Nuclear Research Institute (in the vicinity of the Mt. Elbrus, Kabardino-Balkaria) at the depth of about 1 km underground, which protects it from cosmic rays and diminishes seismic and other disturbances. At the design level the system has sensitivity to gravitational waves, however it has to be put into the mode of continuous operation, which requires additional financing. Besides, its comparatively moderate sensitivity is yet to be enhanced.
"We are moving towards higher sensitivity, but it requires several complicated tasks to be solved first", - the head of  the Gravitational Measurements Department of the Shternberg State Astronomy Institute, Valentina Rudenko says.
A Beam between Two Mirrors
It is noteworthy that the Russian antenna has an optical resonator connected to the detector of acoustic waves.
The resonator consists of two mirrors with a beam running between them and creating a great number of reflections. The gravitational wave interacts with this optical component, that is directly with the light in there as well. Such an antenna will give information about the direction, which the wave comes from.
Now researchers are engaged in tuning the system for working at low temperatures, since the optical resonator is made up of mirrors that have to be cooled down to the nitric temperature. At the same time a one watt beam will hit into them thus heat the system up.