ON THE EMISSION OF HEAVY CLUSTERS FROM MEDIUM MASS COMPOUND NUCLEUS

2011 ◽  
Vol 20 (04) ◽  
pp. 1054-1057
Author(s):  
◽  
G. ADEMARD ◽  
J.P. WIELECZKO ◽  
E. BONNET ◽  
A. CHBIHI ◽  
...  
Keyword(s):  
Atomic Number ◽  
Compound Nucleus ◽  
Cross Sections ◽  
Incident Energy ◽  
Charged Particles ◽  
Binary Fission ◽  
Medium Mass ◽  
Light Particles ◽  
The Cross ◽  
Light Charged Particles

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.

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.

Interaction of 14.0 MeV-Neutrons with 12C in Stilbene

1971 ◽  
Vol 26 (2) ◽  
pp. 317-319 ◽  
Author(s):  
H.-U. Fabian
Keyword(s):  
Cross Sections ◽  
Pulse Shape ◽  
Charged Particles ◽  
Pulse Height ◽  
Pulse Height Spectrum ◽  
Pulse Spectrum ◽  
Heavy Charged Particles ◽  
The Cross

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.

A STUDY OF THE Be9(He3, n)C11 REACTION

1963 ◽  
Vol 41 (7) ◽  
pp. 1036-1046 ◽  
Author(s):  
L. van der Zwan ◽  
A. T. Stewart ◽  
J. Y. Park ◽  
E. Merzbacher
Keyword(s):  
Compound Nucleus ◽  
Cross Sections ◽  
Interaction Mechanism ◽  
Direct Interaction ◽  
Particle Energy ◽  
Energy Spectra ◽  
Angular Distributions ◽  
Proton Recoil ◽  
The Cross ◽  
Photographic Emulsions

The energy spectra and angular distributions of the emergent neutrons from the Be9(He3, n)C11 reaction have been obtained for an incident He3-particle energy of 2 Mev with the technique of observing proton recoil in photographic emulsions. The cross sections were normalized to Be9(He3, p)B11 data observed simultaneously at 90° to the beam. The lack of similarity in the (He3, n) and (He3, p) mirror reactions to some residual states suggests a direct interaction mechanism rather than compound nucleus. An attempt to analyze some of the data in terms of double particle stripping has been made.

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.

COLD FUSION REACTIONS USING NEUTRON-RICH PROJECTILES

2013 ◽  
Vol 22 (08) ◽  
pp. 1350061 ◽  
Author(s):  
A. SULAKSONO
Keyword(s):  
Cross Section ◽  
Compound Nucleus ◽  
Cross Sections ◽  
Estimation Method ◽  
Cold Fusion ◽  
Evaporation Residue ◽  
Fusion Reactions ◽  
Fusion Barrier ◽  
The Cross ◽  
Evaporation Residues

This paper studies the formation cross-sections of super heavy (SH) nuclei in some cold fusion reactions of radioactive neutron-rich projectiles with double-magic 208 Pb target. In this study, the cross-sections of capture, fusion and evaporation residues in one- and two-neutron (1n and 2n) channels are calculated by using neutron-rich Fe , Ni and Zn projectiles are compared to the cross-sections calculated using stable Fe , Ni and Zn projectiles. The heights of fusion barrier and their positions in all reactions considered in this study are also compared to the heights and positions calculated using the estimation method proposed by Dutt and Puri. For cold fusion reactions with stable Fe , Ni and Zn projectiles, the heights of fusion barrier and the cross-sections of evaporation residues in 1n and 2n channels are compared to their corresponding experimental data. In general, for reactions using projectiles with the same proton number, the neutron-rich projectile is found to yield relatively-heavier mass of SH nucleus and larger evaporation residue cross-section, compared to those of the corresponding stable projectiles. However, in certain reactions, the cross-sections of neutron-rich projectile can be slightly larger or slightly smaller than that of the corresponding stable projectile. This behavior is highly affected by the charge of projectile and the fission barrier of the formed compound nucleus (CN). In addition, the 292114 is found to be the heaviest compound nucleus formed in cold fusion reaction by using neutron-rich nuclei as the projectile, but the cross-section of evaporation residue in one-neutron channel is still around few pico barns (pb).

scholarly journals Dependence of the ROT effect on the energy of different light charged particles and on the incident neutron energy

2021 ◽  
Vol 256 ◽  
pp. 00006
Author(s):  
Irina Guseva ◽  
Alexei Gagarski ◽  
Friedrich Gönnenwein ◽  
Yuri Gusev
Keyword(s):  
Angular Distribution ◽  
Angular Velocity ◽  
Compound Nucleus ◽  
Charged Particles ◽  
Ternary Fission ◽  
Incident Neutron ◽  
Incident Neutron Energy ◽  
Trajectory Calculations ◽  
The Moment ◽  
Light Charged Particles

The shift of the angular distribution of different light charged particles in ternary fission of 235U induced by polarized neutrons, the so-called ROT effect, was estimated by modified trajectory calculations, which take into account the rotation of the compound nucleus. In previous publications only α-particles were considered. It is shown here that inclusion of tritons significantly improves the agreement of the energy dependence of the ROT effect with experiment while the inclusion of 5He particles practically does not influence this dependence. In particular, the change in the magnitude of the ROT effect depending on the energy of incident neutrons is correctly predicted. Also, the ROT effect for gamma quanta and neutrons in binary fission is discussed along the same lines, because all mentioned effects are proportional to the effective angular velocity of the compound nucleus at the moment of scission.

scholarly journals The emission of light charged particles in the slow neutron fission of uranium

1948 ◽  
Vol 241 (833) ◽  
pp. 323-343 ◽  
Keyword(s):  
Long Range ◽  
Fission Fragment ◽  
Short Range ◽  
Photographic Plate ◽  
Charged Particles ◽  
Slow Neutron ◽  
Neutron Fission ◽  
Green Is ◽  
Light Particles ◽  
Light Charged Particles

This paper describes the extension of the photographic plate technique to the recording of fission fragment tracks and the application of this method to the study of rare modes of fission in the case of the slow neutron fission of uranium. The emission of a short-range group of light particles in the fission of U 235 , reported by Cassels, Dainty, Feather & Green, is confirmed and the angular and range distributions of these particles described. In addition, the emission of long-range light particles with ranges up to 45 cm. of air is described. The abundance of this mode of fission is 1 in 340 + 40 fission events. The angular and range distributions of these long-range particles are given.

Luminescence of Diatomic Molecules II. Energy Dependence of Collisional Deactivation Cross Sections

1972 ◽  
Vol 27 (5) ◽  
pp. 769-776 ◽  
Author(s):  
F. J. Comes ◽  
F Speier
Keyword(s):  
Excited States ◽  
Cross Section ◽  
Cross Sections ◽  
Charged Particles ◽  
Molecular Ions ◽  
Thermal Velocity ◽  
Vibrational States ◽  
Molecular Gases ◽  
Exponential Law ◽  
The Cross

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

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