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Nucleus-2010 Methods of Nuclear Physics for Femto- and Nanotechnologies |
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LX International Conference on Nuclear Physics Date: 6-9 July 2010 Place: Russia, St. Petersburg, Peterhof, State University Russian Academy Of Sciences Petersburg Nuclear Physics Institute Section 1 "Experimental Study of Nuclear Properties and Fundamental Interactions". "Study Fresnel phase shifts in the differential cross sections and their relationship with the shape of the nuclei" V.V. Dyachkov, A.V. Yushkov, A.L. Shakirov In [1,2] theoretically predicted the existence of Fresnel phase shifts (PSF) in the differential cross sections for elastic scattering of ions at large Sommerfeld parameters. These shifts are the extrema of the oscillations of differential cross sections determined by the shape of the nuclei: for spherical nuclei (signb = 0) are not available; for deformed oblate nuclei (signb < 0) the extrema of Fresnel oscillations are shifted toward larger angles (compared to the angular position of the extrema for a spherical nucleus of the same mass); for deformed prolate nuclei (signb > 0) PSF shifted toward small angles. We first obtained for an array of heavy nuclei on the basis of measurements and generalizations from literary sources the experimental values of the PSF, which vary in the range 0.5-3.00. Studies have shown that the magnitudes and signs of nuclear quadrupole non-sphericity derived from the PSF in satisfactory agreement with those values obtained previously from the effects of shifts Blaire's phases [3,4]. Significant difference phenomenon of PSF from the phenomenon of shifts Blaire's phases is that the PSF observed in the extremes of the elastic scattering without recourse to data on inelastic scattering. This allows you to measure the first signs of nuclear non-sphericity for the odd nuclei, in which, as a rule, the inelastic scattering is strongly suppressed due to the spin-spin interaction. Thus, our findings for the surface shape of odd nuclei were in addition to "The surface of the nuclear deformation b(Z,N)", obtained earlier in [4]. Literature 1. V.V. Kotlyar, A.V. Shebeko // About the diffraction phenomena in the elastic scattering of heavy ions. Nuclear Physics, v. 34, no.2 (8), 1981, pp. 370-385. 2. V.V. Kotlyar, A.V. Shebeko // Effects of higher approximations in the parameters of nuclear deformations in the elastic scattering of heavy ions. Nuclear Physics, v. 35, no. 4, 1982, pp. 912-916. 3. N.N. Pavlova, A.V. Yushkov // Direct measurement of the sign of the deformation of nuclei by shear blerovskih phases. JETP Letters, Volume 20, no. 7, 1974, p. 501-503. 4. A.V. Yushkov // Surface b(Z, N) nuclear deformations for nuclei with Z = 2-102. Nuclei, v. 24, no. 2, 1993, pp. 348-408. Section 5 "Experimental Techniques and Their Applications". "Study of the calorimetric effect of natural radioactivity with the inclusive energy and mass spectra" V.V. Dyachkov, A.L. Shakirov, A.V. Yushkov In search of alternative energy sources hold a special place to develop techniques of recycling radioactive decay and the kinetic energy fluxes of elementary particles and ions. In numerous works the energy of radioactive decay used to create electric batteries, typically for use in spacecraft. Numerous measurements of the calorimetric effect are knew that arises in the active zones of nuclear reactors [1]. We have established experimental systems to study the calorimetric effect of underground streams of neutrons, isotopes of radon, as well as from cosmic radiation. Applied to the measurement was to determine the volume of "critical mass" of the absorbing material to obtain a noticeable calorimetric effect. The fundamental aim is to attempt to determine the differential energy spectrum of cosmic rays in the region of ultrahigh energies. The figure shows the results of measurements on an experimental model with a volume of working fluid 10-3 m3. The method of differential thermocouples with termooporoy in the form of liquid nitrogen was used. It is seen that the calorimetric effect in these conditions is noticeable. To go to higher energies constructed a model with a working volume of 1 m3. In this model provides the possibility of registration of individual particles of ultrahigh-energy track-and autoradiographic methods. Literature 1. V.I. Vladimirov // Practical problems in the operation of nuclear reactors / Moscow, Atomizdat, 1976 S. 296. ... some moments of conference ...
Participant: Dyachkov V.V. Source of Conference: LX International Conference on Nuclear Physics NUCLEUS-2010
Russia, St. Petersburg, Peterhof, State University Russian Academy Of Sciences Petersburg Nuclear Physics Institute, 6-9 July 2010 |
