Yu. P. Popov

Time Reversal Invariance and Parity Violation in Neutron Reactions

Introductory overview, V.E. Bunakov sign correlation in PV effects, M.B. Johnson calculation of the weak matrix elements between compound states, V.V. Flambaum PV potentials in nucleon - nucleon interactions, G.A. Lobov reactions test of TRI, E.B. Davis strength and level densities - from compound nuclear spectroscopy to symmetries violations, S. Tomsovic charged particle tests of P- and T-violation with interfering resonances, G. Mitchell mass dependence of the effective weak couplings, A. Hayes feasibility study of T-violation with nuclei of Van Vleck ions, M. Goldman P- and T-violation in neutron-nucleus reactions - experiments in Japan, A. Masaike PV study with polarized targets and nonpolarized neutrons, L.B. Pikelner test of TRI in proton deuteron transmission, S.M. Beyer Neutron spin rotation and P-, T-violation KEK experiment, Y. Masuda new possibility for search P-, T-violation, A.P. Serebrov. (Part contents).

Investigation of α-decay of 148Sm resonance states

Abstract By means of two large multisectional grid ionization chambers the yield of the 147 Sm (n, α) 144 Nd reaction in the neutron energy interval E n ≈ 0–230 eV was measured. The α-particle spectra of the decay of 14 resonances were obtained. The values of the total α-widths or their upper limits were calculated for 24 resonances. The partial α-widths of transitions to the ground and two first excited levels of the final nucleus and the spin of 10 resonances are given. A comparison of the partial and total α-widths with statistical-model predictions was made. The prediction of the α-width distribution is reasonably consistent with the experimental one. This may be regarded as a confirmation of the Porter-Thomas assumptions concerning the distribution of partial α-widths and the independence of fluctuations of the reduced α-widths in the individual exit channels. There was made an attempt to interpret some of the results obtained and their relationship to decay characteristics on the basis of the semi-microscopic description of high excited states proposed by V.G. Soloviev.

Investigation of the (n, α) reaction on sm and nd isotopes in the neutron energy region below 1 keV

Abstract Alpha widths for sixteen resonances in the 149Sm(n, α) reaction have been measured on the IBR Pulsed Reactor of the Joint Institute for Nuclear Research. The results obtained are discussed together with the improved data on α-widths for the 143Nd, 145Nd and 147Sm resonances in the neutron energy region 0.04–900 eV. From the dependence of α-widths on resonance spins, spin assignment of the 143Nd resonances is made. The experimental values of the average α-widths for the given isotopes are compared with those calculated from the statistical nuclear model. The effect of neutron pairing correlations on the probability of α-decay of excited states is discussed. Alpha-width fluctuations relative to the average value are considered.

Alpha decay from excited states of samarium isotopes

The (n,α) reactions on 147Sm and 149Sm have been investigated at neutron energies up to 200 eV. The life times with respect to alpha-decay have been obtained for thirteen excited states of 148Sm and 150Sm with Jπ = 4- and 3-. Calculations, made according to the statistical theory, of the probabilities of 4- → 2+ transitions in 150Sm are in good agreement with the experiments. The life times of nine 148Sm states are in the region of 0.2 to 4 ns. The life times of the 3- and 4- levels differ by an order of magnitude.

Conception of electron beam‐driven subcritical molten salt ultimate safety reactor

This paper is a preliminary sketch of a conception to develop the ‘‘ultimate safety reactor’’ using modern reactor and accelerator technologies. This approach would not require a long‐range R&D program. The ultimate safety reactor could produce heat and electric energy, expand the production of fuel, or be used for the transmutation of long‐lived wastes. The use of the combined double molten salt reactor system allows adequate neutron multiplication to permit using an electron accelerator for the initial neutron flux. The general parameters of such a system are discussed in this paper.

Levels of 137Ba studied with neutron-induced reactions

Abstract The nucleus 137 Ba has been studied via primary and secondary γ-rays as well as γγ-coincidences following thermal-neutron capture and inelastic neutron scattering. A level scheme was established up to 4.7 MeV consisting of 37 levels including 91 transitions. The neutron binding energy was determined to be 6905.59(8) keV. The thermal-neutron-capture cross section and isomer production of the 11 2 − state at 661.6 keV were determined to be 0.65 −0.04 +0.08 and 0.0098(4) b respectively. The experimental data on excitation energies and electromagnetic properties are compared with predictions of the SU(5) limit of the interacting boson-fermion model. A satisfactorily good agreement between experiment and theory can be stated.

Measurement of neutron capture on 48Ca at thermal and thermonuclear energies.

At the Karlsruhe pulsed 3.75 MV Van de Graaff accelerator the thermonuclear

Cross section of 36S(n, gamma )37S.

^{48}\mathrm{Ca}

Observation of neutron standing waves at total reflection of polarized neutrons by precision gamma-spectroscopy

(n,\ensuremath{\gamma}

Neutron capture of 26Mg at thermonuclear energies

{)}^{49}