V.N. Rudenko

The hypothesis of the variations of the gravitational constant when the distance between the attracting masses is increased is considered. It is shown that at the present time there are two possible ways of checking this hypothesis experimentally. The first consists in using sensitive modern gradiometers to measure G at distances ~ 10m with an accuracy of 1%. The second consists in using second-generation gravitational antennas, which should enable one to measure G at distances ~100 m with an accuracy of 0,1%. In the latter case the experiment is identical with the procedure for calibrating a gravitational antenna in components of the Riemann tensor. The results of these experiments enable one to formulate limitations on the mass of the particles of the hypothetical field responsible for the interaction, which differs from the Newtonian field.

V.B. Braginskii, Yu.B. Lanin and V.I. Panov

The construction of a displacement transducer for a gravitational antenna based on a superconducting microwave resonator of special construction which enables the effect of low-frequency seismic interference to be reduced, is proposed. A theoretical and experimental investigation of this transducer is described.

F.A. Korolev and V.G. Bogomolov

The field distribution of the radiation at the output of a confocal unstable resonator at a wavelength of 7.2 mm is measured. The results are compared with theory for the far-field region. The results obtained confirm the correctness of the theoretical approach used and enable the degree of directivity of the output radiation to be estimated.

V.S. Anchutkin

A practical method of measuring small transverse vibrations of diffusely reflecting objects, the basic principle of which is the use of the oscillatory motion of a system of Interference fringes modulating the spectrum-structure of the scattered field, is described. The main element of the system is a diffraction grating with specularly reflecting rulings and transparent gaps between them, which serve simultaneously to illuminate the specimen and to spatially filter the scattered radiation.

A.N. Goryaga and L.A. Skipetrova

The magnetization Is and coercive force Hс of ferrites of the system $NiFe_{2-x}VxO_{4}$ where x = 0.00, 0.25, 0.50, 0.67, 0.80 and 1.00 are invesdtigated. The effective value of the magnetic anisotropy constants are found for all the specimens using the equation |K$_eff$| = 4ПIsHс at 80K. It is shown that the contribution of the $V^{3+}_B$ ions to the magnetic anisotropy is small and has a positive sign. It is suggested that in the crystal field of an octahedral complex the orbital triplet of the $V^{3+}$ ion is split in such a way that the orbital singlet becomes lower.

L.P. Belov, A.N. Goryaga and L.G. Antoshina

Были изучены температурные зависимости энергии активации, магнитострикции, магнетосопротивления и других магнитных свойств медного феррита в низких температурах. На основе полученных экспериментальных данных сделан вывод о том, что аномальное поведение магнитострикции медного феррита связано с возникновением в низких температурах прямого обменного взаимодействия.

I.I. Pasha

E.I. Shakhnovich

A.D. Okhotsimskii

V.I. Grigor'ev

We examine theoretically the dependence of the probabilities of elastic and inelastic processes on the intensity of boson beams incident on a "target". As the intensity increases, the probabilities initially grow (generally not according to a linear law), reach a maximum, and then begin to die away. The maxima discussed in this paper are of a purely kinematical origin: they are due to the boson statistics and not to possible resonant properties of the target. Estimates are made for the optimum case, where all the boson wave packets are identical and interference effects are therefore most noticeable.