scholarly journals Continuous spectra of light charged particles from interaction of 30 MeV energy protons with cooper

2020 ◽  
Vol 239 ◽  
pp. 01033
Author(s):  
Timur Zholdybayev ◽  
Zhuldyz Mukan ◽  
Bakhtiyar Sadykov ◽  
Bek Duisebayev ◽  
Maulen Nassurlla ◽  
...  

This paper presents the experimental double-differential and integral cross sections of reactions (p,xp), and (p,xα) on natCu nucleus. The experiment with the protons, accelerated to energy of 30.0 MeV was performed at the isochronous cyclotron of Institute of Nuclear Physics (Kazakhstan). We investigated the adequacy of the theoretical models in explaining the measured experimental data and contributions of direct, preequilibrium and compound processes in the formation of the cross sections were determined. We assert that the traditional frameworks are valid for the description of the experimental data.

2011 ◽  
Vol 20 (04) ◽  
pp. 1054-1057
Author(s):  
◽  
G. ADEMARD ◽  
J.P. WIELECZKO ◽  
E. BONNET ◽  
A. CHBIHI ◽  
...  

Fragments with atomic number 6≤ Z ≤28 were measured in singles and in coincidence with emitted light charged particles in the 78 Kr +40 Ca reactions at 5.5 AMeV incident energy by means of the 4π-INDRA array at GANIL. Kinematical features of the fragments are compatible with a binary fission from compound nucleus. The cross-sections σZ indicate the coexistence of macroscopic behaviour and structure effects. Fragment-particle coincidences show that fragments with Z ≤12 are excited below the separation energies of light particles.


2016 ◽  
Vol 104 (8) ◽  
Author(s):  
Junhua Luo ◽  
Chunlei Wu ◽  
Li Jiang ◽  
Long He

Abstract:The cross sections for (n,x) reactions on samarium isotopes were measured at (d-T) neutron energies of 13.5 and 14.8 MeV with the activation technique. Samples were activated along with Nb and Al monitor foils to determine the incident neutron flux. Theoretical calculations of excitation functions were performed using the nuclear model codes TALYS-1.6 and EMPIRE-3.2 Malta with default parameters, at neutron energies varying from the reaction threshold to 20 MeV. The results were discussed and compared with experimental data found in the literature. At neutron energies 13.5 and 14.8 MeV, the cross sections of the


1971 ◽  
Vol 26 (2) ◽  
pp. 317-319 ◽  
Author(s):  
H.-U. Fabian

AbstractThe pulse height spectrum of all heavy charged particles induced by 14.0 MeV neutrons in a 1" × 1" stilbene scintilla­ tor was measured using a pulse shape discriminator and the associated particle technique. The proton pulse spectrum was subtracted and the remaining alpha-pulse distribution is shown in a diagram. The sum of the cross sections for the reactions 12C (n, n') 3 α and 12C (n, α)9 Be was determined to be σc= (260±20) mb.


2018 ◽  
Vol 18 (4) ◽  
pp. 362-378
Author(s):  
Yu. A. Gosteev ◽  
A. D. Obukhovskiy ◽  
S. D. Salenko

Introduction. The technique of numerical modeling of the transverse flow over span structures of bridges on the basis of the two-dimensional URANS (Unsteady Reynolds-averaged Navier-Stokes) approach used in the modern methods and software packages for computational fluid dynamics is verified. The work objective was debugging and experimental substantiation of this technique with the use of the database on the aerodynamic characteristics of the cross-sections of span structures of girder bridges of standard shapes pre-developed by the authors.Materials and Methods. A numerical simulation of the transverse flow of low-turbulent (smooth) and turbulent air flows around the bridge structures in a range of practically interesting attack angles is carried out. SST  k − ω turbulence model was used as the closing one. The technique was preliminarily tested on the check problem for the flow of the rectangular crosssection beams. Calculations were carried out using the licensed ANSYS software.Research Results. The calculated dependences on the attack angle of the aerodynamic coefficients of forces (drag and lift) and the moment of the cross sections of the girder bridges of standard shapes are obtained. These data refer to the span structures at the construction phase (without deck and parapets, without parapets) and operation phase, under the conditions of model smooth and turbulent incoming flow. The latter allows us to outline the boundaries for more weighted estimates of the aerodynamic characteristics of thegirder bridges in a real wind current. The best agreement with the experimental data was obtained from the drag of the cross-section. The magnitude of the lifting force is more sensitive to the presence and extent of the separation regions, so its numerical determination is less accurate. The reproduction of the angle-of-attack effect on the aerodynamic moment of the cross-section is the most challenging for the majority of configurations.Discussion and Conclusions. Comparison of the calculated and experimental data indicates the applicability of the URANS approach to the operational prediction of the aerodynamic characteristics of the single-beam span structures. In the case of multi-beam span structures, where the aerodynamic interference between separate girders plays an important role, the URANS approach must apparently give way to more accurate eddy-resolving methods. The results obtained can be used in the aerodynamic analysis of structures and in practice of the relevant design organizations in the field of transport construction.


Author(s):  
Susshma Nagarajan ◽  
Deepa Seetharaman ◽  
Gowrishankar Ramadurai

Synthesizing nuclei through reactions that produce a reasonable yield is important for the experimental study of neutron-rich nuclei. In this study, the cross-section values of 184Ta and 186Ta nuclei in various experiments were reviewed and analysed. The experimental data of (n, p), (p, x) and (n, α) reactions were compared to identify the best reaction to produce these nuclei for further study. Our study shows that (n, p) reactions on natural Tungsten targets are the most feasible reactions with a good yield of the neutron-rich Tantalum isotopes. New reactions have been proposed for the effective synthesis of 184Ta and 186Ta using tritium beams on Hafnium targets. The cross-section values of the proposed reactions were calculated by PACE4 software simulations.


1983 ◽  
Vol 55 (4) ◽  
pp. 656-660 ◽  
Author(s):  
V. N. Dushin ◽  
A. V. Fomichev ◽  
S. S. Kovalenko ◽  
K. A. Petrzhak ◽  
V. I. Shpakov ◽  
...  

1972 ◽  
Vol 27 (5) ◽  
pp. 769-776 ◽  
Author(s):  
F. J. Comes ◽  
F Speier

Abstract Photoionization has been used to produce ions of N2, O2. and CO in definite excited states. Deactivating collisions of these ions with molecular gases were described in paper I, where the cross sections of ions with thermal velocity are given for various electronic and vibrational states. By application of an electric field the charged particles are accelerated yielding information on the influence of the kinetic energy of the collision partners on these deactivating collisions. The cross section is found to follow an exponential law σ ~ E-α, with a varying between 0.34 and 0 41 for the different excited stales of the molecular ions. The observations were carried out for a range of kinetic energies from the thermal energy up to 6 eV maximum. This simple exponential law is followed for kinetic energies up to at least 2 eV. At higher energies slight deviations were found to occur


2020 ◽  
Vol 239 ◽  
pp. 03021
Author(s):  
Andrey Denikin ◽  
Alexander Karpov ◽  
Mikhail Naumenko ◽  
Vladimir Rachkov ◽  
Viacheslav Samarin ◽  
...  

The paper describes the NRV web knowledge base on low-energy nuclear physics developed in the Joint Institute for Nuclear Research. The NRV knowledge base working through the Internet integrates a large amount of digitized experimental data on the properties of nuclei and nuclear reaction cross sections with a wide range of computational programs for modeling of nuclear properties and nuclear dynamics. Today, the NRV becomes a powerful instrument for nuclear physics research as well as for educational applications. Advantages of the functioning scheme of the knowledge base provide the synergy of coexistence of the experimental data and computational codes within one platform.


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