Dolgikh G.I., Valentin D.I., Batyushin G.N., Dolgikh S.G., Kovalev S.N., Koren' I.A., Ovcharenko V.V., Yakovenko S.V. «Seismoacoustic hydrophysical complex for monitoring the atmosphere–hydrosphere–lithosphere system» Приборы и техника эксперимента, 45, № 3, с. 120-122 (2002)

The seismoacoustic hydrophysical complex intended for investigation of the interaction of geospheres wave fields in a frequency range from 1 μHz to 1 Hz is described. The complex consists of a shorebased system of laser strain meters, laser nanobarograph, bottom station with a hydrophone and a temperature-sensitive element, weather station, and seismoacoustic radiator. The use of modern laser-interferometry methods provided a deformation sensitivity of ≈10^–10 and an atmospheric-pressure sensitivity of 10 mPa.

Verkhoturov V.I., Grafodatskij O.S., Zhukov V.K., Ekimenko V.Yu., Kargapol'tsev A.V., Rudenko V.N., Simanchuk V.I. «Installation for acoustic sounding of electric fields in dielectric materials» Приборы и техника эксперимента, 34, № 2, с. 186-190 (1991)

The installation was described permitting to study accumulation and relaxation processes of space change and electric field connected with it. The spatial resolution of the installation when using OGM-20 laser was ≈100 μm for polymethylmethacrylate samples. The spatial resolution can be reached to several micrometers due to nanosecond LP-3 lasers, providing the formation in solid state media of acoustic signals of the length up to several nanoseconds and below. In connection with it the investigation of thin (tens-hundreds micrometers) dielectric and polymer films is possible.

Volovik G.E. «First law of de Sitter thermodynamics» Письма в ЖЭТФ, 122, № 10, с. 806-808 (2025)

The de Sitter state has a special symmetry: it is homogeneous, and its curvature is constant in space. Since all the points in the de Sitter space are equivalent, this state is described by local thermodynamics. This state has the local temperature T≪em>H/π (which is twice the Gibbons–Hawking temperature), the local entropy density, the local energy density, and also the local gravitational degrees of freedom – the scalar curvature and the effective gravitational coupling ′K. On the other hand, there is the cosmological horizon, which can be also characterized by the thermodynamic relations. We consider the connections between the local thermodynamics and the thermodynamics of the cosmological horizon. In particular, there is the holographic connection between the entropy density integrated over the Hubble volume and the Gibbons–Hawking entropy of the horizon, S_volume=S_horizon≪em>A/4G. We also consider the first law of thermodynamics in these two approaches. In the local thermodynamics, on the one hand, the first law is valid for an arbitrary volume V of de Sitter space. On the other hand, the first law is also applicable to the thermodynamics of the horizon. In both cases, the temperature is the same. This consideration is extended to the contracting de Sitter with its negative entropy, S_volume=S_horizon≪em>A/4G.

Bavizhev M.D., Burlikov V.L., Vorob'ev S.A., Kargapol'tsev A.V., Simanchuk V.I. «An acoustic method for determination of heavy high-energy charged particle energy» Приборы и техника эксперимента, 34, № 4, с. 47-48 (1991)

A method for determination of heavy charged particle energy using the results of acoustic measurements is suggested. To test the method, the energy of protons has been determined at the IHEP I-100 linac with the following parameters: 100±1 MeV particle energy; 1·10¹⁰–1,5·10¹¹ sm^–2 particle pulse intensity; 0.3–60 μs current pulse length. Determination error for about 100 MeV protons doesn’t exceed 3%.

Voronov B.B., Kokshajskij I.N., Korobov A.I. «Application of microcomputers and the CAMAC system for automation of acoustic measurements» Приборы и техника эксперимента, 34, № 4, с. 96-99 (1991)

An experimental facility for study on acoustic properties of solids operating on-line with the Electronica-NTs-80 microcomputer is described. Operating frequency range is 1–400 MHz, temperature range is 4.2–400 K. The accuracy of determination of acoustic wave velocity relative variation is 10^–7, wave amplitude is ≲2%. The method of quadratures is used for measuring acoustic wave velocity relative variation, attenuation factor and secondary harmonic.