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V. S. Barashenkov

Publications and source records attributed to V. S. Barashenkov.

4 recordsLinked to original sources

Analysis of the JINR p(660 MeV) + 129I, 237Np, and 241Am Measurements with Eleven Different Models

We have analyzed the recent JINR measurements on nuclide production cross sections from interaction of 660 MeV proton beams with radioactive targets of enriched 129I (85% 129I and 15% 127I), 237Np, and 241Am with eleven different models, realized in eight transport codes and event-generators: LAHET (Bertini, ISABEL, INCL+ABLA, and INCL+RAL options), CASCADE, CEM95, CEM2k, LAQGSM+GEM2, CEM2k+GEM2, LAQGSM+GEMINI, and CEM2k+GEMINI. We found out that all these models have problems in a correct description of many of these cross sections, though some of these models describe very well most of the recent measurements done at GSI using inverse kinematics, as well as many other reactions. None of the tested here models is able to reproduce well all the JINR data and all of them should be further improved. Development of a better universal evaporation/fission model should be of a highest priority. We conclude that it is impossible to make a correct choice between fission and fragmentation reaction mechanisms analyzing only measurements on product cross sections; addressing this question would require analysis of two- or multi-particle correlation measurements.

nucl-th

Study of Proton Induced Reactions in a Radioactive 129-I Target at Ep=660 MeV

Two NaI (85% 129-I and 15% 127-I) targets were exposed to a beam of 660-MeV protons. Cross sections for formation of 76 residual nuclei were obtained by the induced activity method. The results are compared with other experimental data on 127-I and theoretical calculations by eleven models contained in the codes LAHET3 (using the Bertini+Dresner, ISABEL+Dresner, INCL+Dresner, and INCL+ABLA options), CASCADE, CEM95, CEM2K, LAQGSM+GEM2, CEM2k+GEM2, LAQGSM+GEMINI, and CEM2k+GEMINI. Most of the models describe spallation products with masses close to the target reasonably well while the reliability of the codes differs greatly in the deep spallation and fission/fragmentation regions. The difficulties in describing products with A=40-80 by all of the codes tested here except for CEM2k+GEMINI and LAQGSM+GEMINI is related to the neglect of fission (and fragmentation) processes for targets as light as 129-I.

nucl-ex

Nuclide Production Cross Sections for 59Co and nat-Cu Irradiated with 0.2 and 2.6 GeV Protons and 0.2 GeV/Nucleon Carbon Ions

Results of experimental cross sections for residual nuclide production in interactions of 200 MeV/A 12C ions and 0.2 and 2.6 GeV protons with nat-Cu, 59Co, and 27Al targets are presented. The residual products are measured at ITEP (Moscow) by gamma-spectrometry with a detector of 1.8 keV resolution in the 1332 keV 60Co gamma-line. The measured data are compared with predictions by the LANL (Los Alamos) code LAQGSM+GEM2 and JINR (Dubna) code CASCADE.

nucl-ex

Launching of Non-Dispersive Superluminal Beams

In this paper we analyze the physical meaning of sub- and superluminal soliton-like solutions (as the X-waves) of the relativistic wave equations and of some non-trivial solutions of the free Schrödinger equation for which the concepts of phase and group velocities have a different meaning than in the case of plane wave solutions. If we accept the strict validity of the principle of relativity, such solutions describe objects of two essentially different natures: carrying energy wave packets and inertia-free properly phase vibrations. Speeds of the first-type objects can exceed the plane wave velocity $c_*$ only inside media and are always less than the vacuum light speed $c$. Particularly, very fast sound pulses with speeds $c_* < v < c$ have already been launched. The second-type objects are incapable of carrying energy and information but have superluminal speed. If we admit the possibility of a breakdown of Lorentz invariance, pulses described, for example, by superluminal solutions of the Maxwell equations can be generated. Only experiment will give the final answer.

physics.class-ph