Semi-empirical systematics for the cross-sections of the reactions (n,α), (n,p) and (n,2n) at 14.5MeV neutrons on the basis of experimental data measured by Lanzhou University

2008 ◽  
Vol 266 (22) ◽  
pp. 4862-4868 ◽  
Author(s):  
Junhua Luo ◽  
Fei Tuo ◽  
Fengqun Zhou ◽  
Xiangzhong Kong
Keyword(s):  
Experimental Data ◽  
Cross Sections ◽  
The Cross ◽  
Semi Empirical

FRAGMENTATION PRODUCTION CROSS-SECTIONS IN RELATIVISTIC COLLISIONS

2006 ◽  
Vol 21 (38) ◽  
pp. 2881-2892 ◽  
Author(s):  
İSKENDER DEMİRKOL
Keyword(s):  
Experimental Data ◽  
Cross Sections ◽  
Reaction Mechanisms ◽  
Production Cross ◽  
Cascade Model ◽  
Exciton Model ◽  
Intranuclear Cascade ◽  
The Cross ◽  
Semi Empirical ◽  
Equilibrium Effect

In this study, the fragmentation production cross-sections of heavy residual nuclides in the reactions 238 U (1 A GeV ) + p and p (1.2 GeV ) + 232 Th were calculated and the production of more than 370 different isotopes for this incident reactions was presented. The calculations were made by using the Cascade-Exciton Model including pre-equilibrium effect, the Intranuclear Cascade Model, the empirical and the semi-empirical parametrization. The results of the cross-sections obtained were compared with available experimental data and examined the relation between each other. It is seen that the precision of this models to estimate residue production cross-sections is still far from the performance required for technical applications and this incident model should be improved to obtain a deeper understanding of the reaction mechanisms involved in the production of isotopes.

Cross sections for d-3H neutron interactions with samarium isotopes

2016 ◽  
Vol 104 (8) ◽  
Author(s):  
Junhua Luo ◽  
Chunlei Wu ◽  
Li Jiang ◽  
Long He
Keyword(s):  
Experimental Data ◽  
Neutron Flux ◽  
Cross Sections ◽  
Theoretical Calculations ◽  
Nuclear Model ◽  
Activation Technique ◽  
Incident Neutron ◽  
Reaction Threshold ◽  
Talys 1.6 ◽  
The Cross

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

SEMI-EMPIRICAL SYSTEMATICS OF (n, 2n), (n, α) REACTIONS CROSS SECTIONS AT 14–15 MeV NEUTRON ENERGY

2008 ◽  
Vol 17 (03) ◽  
pp. 567-583 ◽  
Author(s):  
E. TEL ◽  
Ş. OKUDUCU ◽  
M. H. BÖLÜKDEMIR ◽  
G. TANIR
Keyword(s):  
Cross Sections ◽  
Asymmetry Parameter ◽  
Incident Energy ◽  
Empirical Formulas ◽  
Chi Square ◽  
Fitting Method ◽  
The Cross ◽  
Experimental Values ◽  
Semi Empirical ◽  
Original Formula

In this study we propose new semi-empirical formulas by modifying the formula of Levkovskii with the new parameters for (n, 2n) and (n, α) reactions cross-sections at 14–15 MeV neutron incident energy. The cross sections have been calculated using the asymmetry parameter depending on empirical formulas for the incoming energies of 14–15 MeV neutrons. The parameters obtained by modifying the original formula of Levkovskii and Konno et al. have been determined by applying the least squares fitting method to the experimental cross sections, and the systematics of the (n, 2n) and (n, α) reactions have been studied. We have also suggested different parameters for the empirical formula to reproduce the cross sections of the (n, 2n) and (n, α) reactions for the neutron incident energy of 14–15 MeV. The modified formulas yielded cross sections representing markedly smaller chi-square (χ2) deviations from experimental values, and values much closer to units as compared with those calculated using Levkovskii's and Konno et al. original formulas. The results obtained have been discussed and compared with the other empirical formulas, and found to be well in agreement when used to correlate the available experimental σ(n, 2n) and σ(n, σ) data of different nuclei.

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 ◽  
...  
Keyword(s):  
Experimental Data ◽  
Cross Sections ◽  
Nuclear Physics ◽  
Charged Particles ◽  
Theoretical Models ◽  
Isochronous Cyclotron ◽  
The Cross ◽  
Light Charged Particles

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.

scholarly journals Numerical simulation of the transverse flow over spans of girder bridges

2018 ◽  
Vol 18 (4) ◽  
pp. 362-378
Author(s):  
Yu. A. Gosteev ◽  
A. D. Obukhovskiy ◽  
S. D. Salenko
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Cross Section ◽  
Cross Sections ◽  
Aerodynamic Characteristics ◽  
Transverse Flow ◽  
Single Beam ◽  
Weighted Estimates ◽  
Girder Bridges ◽  
The Cross

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.

scholarly journals Study of the Production Cross-Sections of the Neutron-rich 184Ta and 186Ta

2021 ◽  
Vol 9 (1) ◽  
pp. 25-29
Author(s):  
Susshma Nagarajan ◽  
Deepa Seetharaman ◽  
Gowrishankar Ramadurai
Keyword(s):  
Experimental Data ◽  
Experimental Study ◽  
Cross Section ◽  
Cross Sections ◽  
Good Yield ◽  
Production Cross ◽  
Effective Synthesis ◽  
The Cross

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.

Statistical analysis of experimental data on the cross sections of233,235,238U,237Np,239,242Pu fission by neutrons of energy 2.6, 8.5, and 14.5 MeV

1983 ◽  
Vol 55 (4) ◽  
pp. 656-660 ◽  
Author(s):  
V. N. Dushin ◽  
A. V. Fomichev ◽  
S. S. Kovalenko ◽  
K. A. Petrzhak ◽  
V. I. Shpakov ◽  
...  
Keyword(s):  
Experimental Data ◽  
Statistical Analysis ◽  
Cross Sections ◽  
The Cross

scholarly journals A comprehensive analysis of differential cross sections and analyzing powers in the proton–deuteron break-up channel at 135 MeV

2021 ◽  
Vol 57 (2) ◽  
Author(s):  
H. Tavakoli-Zaniani ◽  
M. Eslami-Kalantari ◽  
H. R. Amir-Ahmadi ◽  
M. T. Bayat ◽  
A. Deltuva ◽  
...  
Keyword(s):  
Experimental Data ◽  
Cross Section ◽  
Cross Sections ◽  
Theoretical Calculations ◽  
Nucleon Force ◽  
Satisfactory Description ◽  
Analyzing Powers ◽  
Global Comparison ◽  
Break Up ◽  
The Cross

AbstractA selection of measured cross sections and vector analyzing powers, $$A_{x}$$ A x and $$A_{y}$$ A y , are presented for the $$\vec {p}{d}$$ p → d break-up reaction. The data are taken with a polarized proton beam with a kinetic energy of 135 MeV using the Big Instrument for Nuclear-polarization Analysis (BINA) at KVI, the Netherlands. With this setup, $$A_{x}$$ A x is extracted for the first time for a large range of energies as well as polar and azimuthal angles of the two outgoing protons. For most of the configurations, the results at small and large relative azimuthal angles differ in behavior when comparing experimental data with the theoretical calculations. We also performed a more global comparison of our data with theoretical calculations. The cross-section results show huge values of $$\chi ^{2}$$ χ 2 /d.o.f.. The absolute values of $$\chi ^{2}$$ χ 2 /d.o.f. for the components of vector analyzing powers, $$A_{x}$$ A x and $$A_{y}$$ A y , are smaller than the ones for the cross section, partly due to larger uncertainties for these observables. However, also for these observables no satisfactory agreement is found for all angular combinations. This implies that the present models of a three-nucleon force are not able to provide a satisfactory description of experimental data.

scholarly journals Effects of Proximity Potentials on the Cross-Sections of 6,8He + 65Cu Halo Fusion Reactions

2019 ◽  
Vol 64 (5) ◽  
pp. 363
Author(s):  
M. Aygun
Keyword(s):  
Experimental Data ◽  
Cross Sections ◽  
Theoretical Study ◽  
Fusion Reactions ◽  
The Cross ◽  
Theoretical Results

The comprehensive theoretical study is performed to determine the best proximity potentials in reproducing 6,8He + 65Cu fusion reactions. Twenty three different versions of proximity potentials that consist of Prox 66, Prox 76, Prox 77, Prox 79, Prox 81-I, Prox 81-II, Prox 81-III, Prox 84, Prox 88, Mod-Prox-88, Prox 95, Prox 2003-I, Prox 2003-II, Prox 2003-III, Prox 2010, BW 91, AW 95, Bass 73, Bass 77, Bass 80, CW 76, Ngo 80, and D are used. The theoretical results are compared with experimental data on 6,8He + 65Cu fusion reactions. The appropriate proximity potentials are determined.

scholarly journals PROMPT PHOTON PRODUCTION IN p-p COLLISIONS

1995 ◽  
Vol 10 (20n21) ◽  
pp. 2941-2960 ◽  
Author(s):  
J. CLEYMANS ◽  
E. QUACK ◽  
K. REDLICH ◽  
D.K. SRIVASTAVA
Keyword(s):  
Experimental Data ◽  
Cross Section ◽  
Cross Sections ◽  
Systematic Study ◽  
Structure Functions ◽  
Photon Production ◽  
Prompt Photon ◽  
Centre Of Mass ◽  
The Cross ◽  
Photon Cross Section

A systematic study of the inclusive photon cross-section in p-p collisions is presented. The dependence of the γ rates on the renormalization and factorization scales is discussed. A comparison is made with experimental data for centre-of-mass energies ranging from 23 GeV to 1.8 TeV. Predictions of the cross-sections are given for two different sets of structure functions for RHIC and LHC energies.

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