Effective moment of inertia for several fission reaction systems induced by nucleons, light particles and heavy ions

Compound nucleus effective moment of inertia has been calculated for several fission reaction systems induced by nucleons, light particles, and heavy ions. Determination of this quantity for these systems is based upon the comparison between the experimental data of the fission fragment angular distributions as well as the prediction of the standard saddle-point statistical model (SSPSM). For the systems, the two cases, namely with and without neutron emission corrections were considered. In these calculations, it is assumed that all the neutrons are emitted before reaching the saddle point.It should be noted that the above method for determining of the effective moment of inertia had not been reported until now and this method is used for the first time to determine compound nucleus effective moment of inertia. Hence, our calculations are of particular importance in obtaining this quantity, and have a significant rule in the field of fission physics. Afterwards, our theoretical results have been compared with the data obtained from the rotational liquid drop model as well as the Sierk model, and satisfactory agreements were found. Finally, we have considered the effective moment of inertia of compound nuclei for the systems that formed similar compound nuclei at similar excitation energies.Comment: 9 pages, 2 Figures, 2 Table

Synthesis of transactinide nuclei in cold fusion reactions using radioative beams

Chances of synthesis of transactinide nuclei in cold fusion reactions (one-neutron-out) reactions using radioactive beams are evaluated. Because intensities of radioactive beams are in most of the cases significantly lower than the ones of the stable beams, reactions with the highest radioactive beam intensities for the particular elements are considered. The results are compared with the recent ones obtained by Loveland who investigated the same nuclei.Comment: 5 page

Fission Decay Widths for Heavy-Ion Fusion-Fission Reactions

Cross-section and neutron-emission data from heavy-ion fusion-fission reactions are consistent with a Kramers-modified statistical model which takes into account the collective motion of the system about the ground state; the temperature dependence of the location of fission transition points; and the orientation degree of freedom. We see no evidence to suggest that the nuclear viscosity departs from the surface-plus-window dissipation model. The strong increase in the nuclear viscosity above a temperature of ~1 MeV deduced by others is an artifact generated by an inadequate fission model.Comment: 14 pg, 6 fig, submitted to Physical Revie

Scaling of the giant dipole resonance widths in hot rotating nuclei from the ground state values

The systematics of the giant dipole resonance (GDR) widths in hot and rotating nuclei are studied in terms of temperature T, angular momentum J and mass A. The different experimental data in the temperature range of 1 - 2 MeV have been compared with the thermal shape fluctuation model (TSFM) in the liquid drop formalism using a modified approach to estimate the average values of T, J and A in the decay of the compound nucleus. The values of the ground state GDR widths have been extracted from the TSFM parametrization in the liquid drop limit for the corrected T, J and A for a given system and compared with the corresponding available systematics of the experimentally measured ground state GDR widths for a range of nuclei from A = 45 to 194. Amazingly, the nature of the theoretically extracted ground state GDR widths matches remarkably well, though 1.5 times smaller, with the experimentally measured ground state GDR widths consistently over a wide range of nuclei.Comment: 15 pages, 4 figures, Accepted for publication in Physical Review

A simple ansatz for the study of velocity autocorrelation functions in fluids at different timescales

A simple ansatz for the study of velocity autocorrelation functions in fluids at different timescales is proposed. The ansatz is based on an effective summation of the infinite continued fraction at a reasonable assumption about convergence of relaxation times of the higher order memory functions, which have a purely kinetic origin. The VAFs obtained within our approach are compared with the results of the Markovian approximation for memory kernels. It is shown that although in the "overdamped" regime both approaches agree to a large extent at the initial and intermediate times of the system evolution, our formalism yields power law relaxation of the VAFs which is not observed at the description with a finite number of the collective modes. Explicit expressions for the transition times from kinetic to hydrodynamic regimes are obtained from the analysis of the singularities of spectral functions in the complex frequency plane.Comment: 14 pages, 2 figure

Лідерство як системна компетентність майбутнього конкурентоспроможного фахівця

The article is dedicated to improving the quality of the preparation of future competitive engineers in higher education. The paper presents the author's view of the structure and criteria of leadership competencies. The focus is on the ways to develop leadership competencies in the academic environment and modern methods for assessing leadership skills. The significance of leadership as a systemic competence of the future specialist was introduced on the basis of the theoretical and practical experience in pedagogy, psychology and management. The results of psychological and pedagogical research on leadership competencies development of future professionals in the academic environment of the technical university are discussed in the article.Статтю присвячено питанням підвищення якості підготовки сучасних конкурентоспроможних фахівців у вищій школі. У роботі представлений авторський погляд на структуру та критерії лідерських компетентностей. У центрі уваги перебувають способи розвитку лідерських компетентностей в академічному середовищі та сучасні методи оцінки лідерських здібностей. На підставі досвіду теоріїї і практики педагогіки, психології і менеджменту доведена значущість лідерства як системної компетентності майбутнього конкурентоспроможного фахівця. Обговорюються результати психолого-педагогічного дослідження спрямованого на розвиток лідерських компетентностей майбутніх фахівців в освітньому середовищі технічного університету

Activation cross-sections of proton induced reactions on nat^{nat}Sm up to 65 MeV

Activation cross sections for proton induced reactions on Sm are presented for the first time for $^{nat}$Sm(p,xn)$^{154,152m2,152m1,152g,150m,150g,149,148,147,146,145}$Eu, $^{nat}$Sm(p,x)$^{153,145}$Sm, $^{nat}$Sm(p,x)$^{151,150,149,148g,148m,146,144,143}$Pm and $^{nat}$Sm(p,x)$^{141}$Nd up to 65 MeV. The cross sections were measured via activation method by using a stacked-foil irradiation technique and high resolution gamma ray spectroscopy. The results were compared with results of the nuclear reaction codes ALICE, EMPIRE and TALYS (results taken from TENDL libraries). Integral yields of the activation products were calculated from the excitation functions.Comment: arXiv admin note: text overlap with arXiv:1411.716