1. Experimental base of the United Experimental laboratory for Gravitational-Optical Investigations (UELGOI).
The main experimental base of UELGOI is presented by the located in FSPC SIAO specialized compartments, equipped with any necessary facilities: lasers, high-reflective mirrors, polarizing prisms, hologram diffraction gratings, piezoelectric cells, phase modulators, multichannel analyzers of spectral information, photodetectors, radio and optoelectronic devices and computers.
All the investigations are performed in the specialized experimental cage (EC), placed in the underground laboratory (UL) at the depth 12 m from the ground level, what provides minimization of the vibration background effect and reduction of the temperature stabilization problem. The laboratory walls and the flour are displaced in the all-metal chamber, which is rested on the sand cushion and dampproof from the wall sides. The laboratory has technical underground with depth 2 m from the flour level, which serves for installing the foundations of the main equipment of UL as well as for displacing the electric communications and systems of power supply of the main equipment. Experimental cage consists of two departments, one containing another. In the internal compartment all the high-sensitive devices including the developed two-resonator laser system are mounted on the special foundation, which, in its turn, is vibroisolated from the room foundation. The foundation represents the ferroconcrete block of 100 tonn weight and is vibroisolated by means of the spiral car springs. The equipment is additionally vibroisolated by means of various special vibration isolators.
To provide necessary temperature conditions the three-stage system of thermal stabilization is incorporated. the first stage is provided with conditioner, which warms the air flow, coming as an influent ventilation to UL, and keeps the temperature within the limits ±0.250C from the set nominal value. The second and the third stages are provided with specially developed independent system of temperature stabilization. At the second stage the temperature in the external room of the compartment is stabilized within tenths degree from the nominal value, and at the third one the temperature in the internal room of the compartment is correspondingly stabilized within hundredths degree.
2. Passive variant of GW-detector.
The first step in realizing the complex programme of gravitational experiments on "Dulkyn" project was the construction of passive variant of GW-detector on the basis of pentagonal ring two-contour interferometer, which optical radiation source being out of it.
The pentagonal interferometer, operating at the wave length 0,63 mm, was mounted and adjusted on the polished round glass plate of 10 cm thickness and with diameter 65 cm, the pentagonal side being 30 cm, in December of 1995. The following technical problems were solved in the course of test experiments on the passive interferometer:
3. Active-type GW-detector.
The second step in realizing the 'Dulkyn' project is the creation of a prototype of GW detector active variant that is the compact two-resonator laser system.
In summer of 1999 two-resonator laser systems of pentagonal ring configuration (running waves)  and of triangle linear configuration (standing waves)  were built and adjusted. Using these schemes, stable lasing at the wavelength 3,39 mm was obtained.
All the optical elements, forming a specific two-resonator laser system, were rigidly fixed on a single basement. For the pentagonal resonator configuration the plate basement was used, made of thermally treated to stabilize its dimensions aluminum alloy D 16 (its weight is 400 kg), its diameter and thickness being 1,4 m and 8 cm correspondingly. Thermal treatment included four regimes of heating and cooling at various temperatures to remove all the internal strains in metal.
At present time the GW-detector active variant prototype is used to adjust and debug servosystems of frequency and phase stabilization of generated optical radiation.
4. Vacuum chamber.
The specialized vacuum chamber (VC) with diameter 1,7 m and height 0,67 m (550 kg weight) is fabricated, designed to isolate outside the two-resonator laser system. The residual pressure inside the vacuum chamber does not cross the level 10-3 torr.
The two-resonator laser system plate basement rests inside the VC on three bearing supports, displaced at the corners of a proper triangle and distant from the plate centre by 2/3 of its radius.
5. Preparation to performing of calibration for GW-detector the first level of imitation signal (Lunar test).
The following work was fulfilled after restarting of funding since February 2006 till March 2007:
6. Results of Lunar Test experiment.
Long-term continuous Lunar Test experiment has started on 8th of September 2008 and successfully accomplished on 5th of March 2009 by Scientific Center for Gravitational Wave Research (SC GWI) of Tatarstan Republic Academy of Sciencies. Its performance had confirmed the validity of concept for the construction of gravitational wave detector Dulkyn and highlighted accomplishing the first of three successive stages of low frequency gravitational detector creation.
Performance of Lunar Test is the result of theoretical, design and experimental work during more than 15 years effort of the whole set scientific collectives and leading enterprises: AS RT SC GWI Dulkyn, KGU, FGUP NPO GIPO, ннн FITRAN etc.
The success of scientific collective is certified: the diploma and golden medal were acquired by the results of scientific Dulkyn presentation at the international exposition of innovations in Brussels in 2005.
While performing the 1st phase (Lunar Test) of the III (final) stage of scientific-technical project Dulkyn the following tasks were accomplished:
Summarizing the results of the unique experiment Lunar Test, it is necessary to point out that all goals and tasks of the 1st phase of science-technical project Dulkyn ь (final) stage are achieved.
Calibration problem of Dulkyn-1 - extraction of calibration signals in the predetermined infra-low range - is completely fulfilled. Operation ability of detector and all supplementary equipment during many months is proved.
The achieved sensitivity of Dulkyn-1 detector that is 10-12 - 8*10-16 in the frequency range 10-5 - 1 Hz, corresponds to values necessary to detector of the first level and is unique in the world for this infra-low frequency range in present time (up to the launch in 2015 of international space project LISA).
Einstein's equivalence principle is checked (for universality of gravitational red shift law for clocks of various physical nature) at the level of 0.9% that is twice higher than the best world achievement (1.7% - USA, 1983)! The experiment of such a kind was performed for the first time in Russia (and former USSR).
The construction conception validity was confirmed for GW detector Dulkyn, which elasto-dynamic response is calculated on the basis of G. Mozhene approach corresponding to the value of phenomenological parameter ξ=1 in contrast to alternative approach of J. Weber (ξ=0), since experimental value got at the testing of equivalence principle was ξ=1±0.009.
In whole, successful accomplishing of Lunar Test, reach material and experience accumulated during its conduction inspire confidence in fast successful accomplishing of 2nd and 3rd phases tasks for Dulkyn project which final goal is the creation of gravitational wave detector and the beginning of astrophysical research in the field of gravitational wave astronomy.
In the case of science-technical project Dulkyn funding prolongation, the fulfillment of the project 2nd phase will be started that is creation of the second level detector Dulkyn-2 with a sensitivity three orders higher than that of Dulkyn-1. Supposed time of detector Dulkyn-2 creation and calibration is 3 years.
The final goal is the construction of the third level detector Dulkyn-3 with sensitivity three orders higher than Dulkyn-2, i.e. the creation of real gravitational-wave detector capable to discover low-frequency gravitational radiation from double astrophysical objects. SC GWI Dulkyn is open to the collaboration with scientific and commercial organizations that are interested in the prolongation of this work.