Fluctuations and the magnetic equation of state

The influence of inhomogeneity of magnetization on the equation of state for a magnetic system has been considered in the approximation of homogeneous fluctuations of magnetic moment. The fluctuations have been described in the molecular field approximation. It has been shown that taking into account the fluctuations of magnetic moment at the derivation of the equation of state changes the relation among the variablesM, H andT, the temperature dependence of the spontaneous magnetization near the critical point, and shifts the critical temperature.The author would like to thank Prof. J.Kocinski and Prof. L.Wojtczak for their interest in the subject of the paper and for numerous elucidating discussions. The author is indebted to Prof. L.Valenta for his helpful remarks concerning this paper.     

Generalization of von Neumann's theorem to nonreproducible measurements in the framework of quantum field theory. I

One of von Neumann's three theorems - the one on the reduction of the wave packet – is extended to the most general case of nonreproducible measurements in the framework of quantum field theory. The proof of the generalization uses only the most general principles of theory: unitarity of the operator and the standard probability interpretation of the state vector of a physical system.Lecture at the Fall School 1976 on Axiomatic Quantum Field Theory (Uzhgorod, September 15–21, 1976) and at the Nuclear-Physics Section Session of the Academy of Sciences of the USSR (Moscow, February 1–4, 1978).Uzhgorod Branch of Hadron Theory. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 108–113, April, 1978.I am very grateful to Academician N. N. Bogolyubov for approval of the resulta of this paper (preliminary publications of some results were given in [16–22]), to Professors M. I. Podgoretskii (JINR, Dubna), V. Ya. Fainberg (P. N. Lebedev Physics Institute, Moscow) for numerous fruitful and stimulating discussions, to Professor Yu. M. Shirokov (V. A. Steklov Mathematics Institute, Moscow) for valuable comments, and to L Yu. Krivskii and E. P. Sabada for helpful discussions.     

Effect of quenching on the electrical conductivity of doped KCl crystals

Electrical conductivity and optical absorption of divalent cation and anion doped KCl crystals have been measured before and after quenching from 750 °C. The conductivity after quenching is found to decrease in undoped and cation doped crystals while it increases in the anion doped crystals. This is due to higher coagulation rate of cation impurities as compared to anion impurities. Since the divalent impurities diffuse in the form of impurity-vacancy complexs, the higher mobility of cation vacancies (which form dipoles with divalent cation impurities) accounts for the higher aggregation rate of the cation impurities. The aggregation rate, during annealing after quenching, has also been found to depend on concentration.The author is indebted to Prof. H. N.Bose for helpful discussions. Thanks are also due to Dr. M. L.Mukherjee for providing the crystals.     

Spectroscopic studies of Ni2+ in calcium tartrate tetrahydrate

The optical absorption spectrum of a single crystal of calcium tartrate tetrahydrate, doped with Ni²⁺ ions, is investigated at laboratory and liquid nitrogen temperatures. From the analysis of the unpolarised and polarised spectra, the site symmetry of the Ni²⁺ ion is attributed to an elongated octahedron with a small tetragonal (C_4v) distortion.The analysis results in the following crystal field parametersB=875 cm^–1,C=3980 cm^–1,Dq=900 cm^–1, Dt=32cm^–1.The authors wish to express their thanks to the Head of the Department of Physics, I.I.T., Madras for providing the facilities to conduct experiments on a Cary-14 spectrophotometer. They wish to express their thanks to Prof. S.Radhakrishna (I.I.T., Madras) and Prof. S.V. J.Lakshman (S.V. University) for thier interest in the work. The authors are grateful to the U.G.C. (India) for financial assistance.     

Conduction mechanisms in pyrolytically grown dielectrics

Various conduction mechanisms in thin SiO₂, Al₂O₃, In₂O₃ layers were investigated experimentally by analyzing the behavior of the current as a function of field strength and temperature. The films were obtained by pyrolytic dissociation of organic compounds in the vapor phase.The author is indebted to P. S. Kireev for guidance, and to M. I. Elinson and V. B. Sandomirskii for interest in the investigation.     

3MgO · Be2O3 (Ce,Sm), A phosphor with Ce4+-sensitized emission

This phosphor has a strong orange-red emission due to the Sm³⁺, the Ce⁴⁺ serving as activator.I am indebted to M. A. Konstantinova-Shlezinger, M. D. Galanin, V. V. Antonov-Romanovskii, and N. A. Gorbacheva for advice and discussions.     

The adiabatic approximation in problems in nonlinear optics

The frequency dependence in the adiabatic approximation is examined for the third-rank polarizability tensors of a crystal lacking a center of symmetry. These tensors contain electronic, ionic, and mixed terms, the first type being independent of temperature.I am indebted for discussions to L. M. Belyaev, D. N. Zubarev, S. V. Tyablikov, V. V. Nabatov, Yu. V. Pisarevskii, and Yu. V. Shaldin.     

Influence of band non-parabolicity on the oscillatory dependence of the Debye screening length in degenerate semiconductors on magnetic quantization

The Debye screening length in degenerate non-parabolic bands is shown to have an oscillatory dependence on a quantizing magnetic field as in degenerate parabolic bands. The period of oscillations is, however, found to decrease with increasing non-parabolicity which also is observed to have no effect on the amplitude of the same.On leave of absence fromthe Department of Physics, B.N. College, Patna University, Patna 800004.The authors are indebted to Prof. J. N.Bhar for his keen interest in the work.     

The Faraday effect in silicate glasses containing rare earths at low temperatures

The frequency dependence is reported for glasses containing Ce³⁺, Nd³⁺, and Dy³⁺ at 4046–5770 Å at 1.39 to 6.7° K in fields up to 4 kOe. The results are ascribed to allowed 4f ⁿ-4f ^n–1 5d electric-dipole transitions. The concentration dependence at low concentrations has been measured for the Ce³⁺ glass at 1.4° K.We are indebted to V. A. Kaplun, Yu. A. Pereverzev, and E. G. Berzing for the specimens and to I.M. Dmitrenko and V. V. Eremenko for a discussion of the results.     

Cyclotron resonance in a semiconductor in a steady electric field

The classical kinetic equation is solved to find the carrier distribution in the valence band for germanium in cyclotron resonance, the carriers being generated by the electric field. Negative power absorption is demonstrated.I am indebted to V. G. Veselago for proposing the topic and to Yu. M. Kagan for a discussion.     

Elimination of systematic errors in applied accurate lattice parameter measurements

The method of accurate lattice parameters evaluation of polycrystalline materials is described which does not require direct quantitative data expressing the magnitude of systematic errors. Positions of a series of lines in back reflection region are used as input data for the computer evaluation, which are a linear function of the Bragg angle (or its complement) so that in the case of film measurement the diameter of the camera, and in the case of diffractometer measurement, the zero setting of the goniometer need not be determined independently. The method is illustrated in detail for back reflection film measurements in a cylinder camera. The method is aimed at making easy the applied accurate lattice parameter measurements.The author is deeply indebted to the late Professor M. E.Straumanis for valuable discussions in 1970 about the experimental problems of accurate lattice parameters measurements by film method and for making possible to use the original instruments in his laboratory. The author expresses his thanks to Mrs. V.Gregorová and Mr. M.Jelínek for taking part in the experiments.     

On the stationary state of a plasma in magnetostatic and potential fields II

The density distribution on the lines of force of the magnetostatic field is established under certain simplifying conditions for a plasma bounded by a combination of a magnetostatic and a potential field. The distribution functions of the particles, too, are determined for some of the cases being examined. It is found that certain non-linear effects given by the action of the averaged high-frequency forces in the plasma can occur in experiments concerning the magnetoacoustic resonance of the plasma column.The author is indebted to I. A. Kovan, V. D. Rusanov and V. P. Smirnov (Institute of Atomic Energy, Moscow) for valuable discussions concerning the experiments reported in [6 to 8]. His thanks are also due to the participants of the Seminar held on March 15, 1966, at the Institute of Plasma Physics, Czechoslovak Academy of Sciences, for their review of his results.     

Nuclear orientation study of155Tb decay

The angular distribution of gamma-rays following the electron capture decay of¹⁵⁵Tb nuclei oriented in a gadolinium host has been studied at temperatures between 16 and 80 mK. The magnetic dipole hyperfine splitting parameter for¹⁵⁵Tb(Gd) has been deduced and the value of the magnetic dipole moment of¹⁵⁵Tb ground state has been found to be=2.0(2) _N. The multipole mixing ratios have been determined for 9 gamma-transitions in¹⁵⁵Gd.On leave fromthe Department of Physics, University of Jyväskylä, Finland.The authors are indebted to Dr. N. A.Lebedev and to the mass-separator group of Nuclear spectroscopy and radiochemistry department at JINR for preparing the¹⁵⁵Tb activity. The assistance of Ing. M.I.Fominikh and Ing. P.Brada in computer analysis of spectra should be acknowledged. Organisation support of Dr. V. M.Tsupko-Sitnikov and his permanent interest during the course of our work is to be recognized here.     

The existence of (n, γf) process on235U nucleus and uranium X-ray yields

The measurement of X-rays emitted before the fission of²³⁵U induced by resonance neutrons is described. Preliminary results show the dependence of the X-ray yield on fission width _f. It is explained on the bases of the existence of the two-step (n,f) process. The estimate of the width of the (n,f) process is of the order of 4 MeV and the-transitions taking place before fission of²³⁶U compound nucleus are mostly of the M1 type.In conclusion the authors would like to express their gratitude to L. B.Pikelner for many useful discussions, to I. M.Salamattn and A.Mateeva for the programme supply of the experiment, V. G.Tisin, A. A.Bogdzel, Yu. I.Kolgin and N.Chikov for taking part in the different steps of the work. The authors are also grateful toYu. P.Popov and I.Wilhelm for taking interest in the work.     

Measurement of the e+e? → π+π? cross section with the CMD-2 detector in the 370–520-MeV energy range

The results of the experiment on the measurement of the e ⁺ e ⁻ → π⁺π⁻ cross section in a cm energy range of 370–520 MeV are presented. The systematic measurement error is equal to 0.7%. In the vector dominance model, the pion electromagnetic radius is calculated using all the CMD-2 data on the pion form factor. The cross section for the production of a muon pair is measured in the energy range of the experiment. Original Russian Text ? V.M. Aul’chenko, R.R. Akhmetshin, V.Sh. Banzarov, L.M. Barkov, N.S. Bashtovoĭ, D.V. Bondarev, A.E. Bondar’, A.V. Bragin, N.I. Gabyshev, D.A. Gorbachev, A.A. Grebenyuk, D.N. Grigor’ev, S.K. Dhawan, D.A. Epifanov, A.S. Zaĭtsev, S.G. Zverev, F.V. Ignatov, V.F. Kazanin, S.V. Karpov, I.A. Koop, P.P. Krokovny, A.S. Kuz’min, I.B. Logashenko, P.A. Lukin, A.P. Lysenko, A.I. Mil’shteĭn, K.Yu. Mikhaĭlov, I.N. Nesterenko, M.A. Nikulin, A.V. Otboev, V.S. Okhapkin, E.A. Perevedentsev, A.S. Popov, S.I. Redin, B.L. Roberts, N.I. Root, A.A. Ruban, N.M. Ryskulov, A.L. Sibidanov, V.A. Sidorov, A.N. Skrinsky, V.P. Smakhtin, I.G. Snopkov, E.P. Solodov, J.A. Thompson, G.V. Fedotovich, B.I. Khazin, V.W. Hughes, A.G. Shamov, Yu.M. Shatunov, B.A. Shvarts, S.I. éĭdel’man, Yu.V. Yudin, 2006, published in Pis’ma v Zhurnal éksperimental’noĭ i Teoreticheskoĭ Fiziki, 2006, Vol. 84, No. 8, pp. 491–495.     

Hadron-nucleon elastic scattering at high energies

A review of experiments on high energy hadron-nucleon elastic scattering is given. Emphasis is placed on the most recent experiments at FNAL and CERN/ISR. Results (mostly preliminary) are discussed and compared with earlier experiments.Presented at the Symposium on Hadron-Hadron Scattering at High Energies, Liblice, Czechoslovakia, June 16–21, 1975.I like to thank the Czechoslovakian Academy of Sciences and the Organizing Committee of the Symposium, especially Dr. J.Fischer, for their invitation and hospitality. I am indebted to D. D.Jovanovitch of the Michigan-Argonne-Fermilab-Indiana collaboration for sending me their data prior to publication.     

The S-matrix in classical mechanics

In the Hilbert-space version of classical mechanics, scattering theory forN-particle systems is developed in close analogy to the quantum case. Asymptotic completeness is proved for forces of finite range. Infinite-range forces lead to the problem of stability of bound states and can be dealt with only in some simple cases.It is a pleasure to thank Prof.L. Motchane for his kind hospitality at the I.H.E.S., where most of this work was done, and where the author profited from discussions withD. Ruelle andO. E. Lanford.     

Vavilov-Cherenkov radiation in the biaxial triglycine sulphate crystal

Some properties of the Vavilov-Cherenkov radiation in the biaxial triglycine sulphate crystal have been analysed. The radiation properties have been studied for the cases of protons moving along the main three dielectric axes. The measurements were performed with the 660 MeV proton beam.A quantitative agreement of experiment with Muziká's theoretical calculations on the directional properties was observed. In all the cases a qualitative agreement concerning azimuthal distribution of the radiation intensity of the extraordinary waves of both polarities as well as concerning the polarization properties predicted by Obdrálek's formulae has been obtained.Dedicated to the Memory of Professor . Muziká.On leave from Department of Nuclear Physics, Comenius University, Bratislava, Czechoslovakia.The authors are grateful to Prof. V. P.Dzhelepov, Director of the Laboratory of Nuclear Problems, to Prof. L. I.Lapidus for support of the experiment as well as to Prof. L. M.Belyaev and I. V.Gavrilova (the Institute of Crystallography of the USSR Academy of Sciences) for supplying triglycine sulphate crystals, to J.Obdrálek (Charles University, Prague) for fruitful discussions and helpful advice, to Dr. R.Pose for assistance in obtaining negative colour film, to E.Janikova and R.Janik for great assistance in the experiment.     

About X0 (958) spin determination

The likelihood analysis of all the production and decay information about the reaction K^–pX⁰ is suggested, instead of the one-dimensional Adair analysis. It is shown that even the analysis of the present data could yield the likelihood ratio of the 0^– and 2^– hypotheses less than 10^–5.The author is much grateful to V. I.Ogievetsky, V. I.Rud, W.Tybor and A. N.Zaslavsky for valuable discussions.     

Studying of hypernuclei with nuclotron beams

A spectrometer is created to study relativistic hypernuclei produced with beams of accelerated nuclei from the Nuclotron facility (Dubna, JINR). Test runs have been carried out and the conclusion is drawn that the properties of the facility meet the requirements of the task of searching for unknown and studying poorly known neutron-rich hypernuclei. Original Russian Text ? A.V. Averyanov, S.A. Avramenko, V.D. Aksinenko, M.Kh. Anikina, S.N. Bazylev, V.P. Balandin, Yu.A. Batusov, Yu.A. Belikov, Yu.T. Borzunov, O.V. Borodina, A.I. Golokhvastov, L.B. Golovanov, C. Granja, A.B. Ivanov, Yu.L. Ivanov, A.Yu. Isupov, Z. Kohout, A.M. Korotkova, A.G. Litvinenko, J. Lukstiņš, A.I. Malakhov, L. Majling, O. Majlingova, P.K. Manyakov, V.T. Matyushin, I.I. Migulina, G.P. Nikolaevsky, O.B. Okhrimenko, A.N. Parfenov, N.G. Parfenova, V.F. Peresedov, S.N. Plyashkevich, S. Pospišil, P.A. Rukoyatkin, I.S. Saitov, R.A. Salmin, V.M. Slepnev, I.V. Slepnev, M. Solar, B. Sopko, V. Sopko, E.A. Strokovsky, V.V. Tereshchenko, A.A. Feshchenko, T. Horazdovsky, D. Chren, Yu.A. Chencov, I.P. Yudin, 2008, published in Yadernaya Fizika, 2008, Vol. 71, No. 12, pp. 2137–2145.