DECAY PROPERTIES OF SHORT LIVED RESONANCES OF LIGHT NUCLEI IN MANY-PARTICLE NUCLEAR REACTIONS

2010 ◽  
Vol 19 (05n06) ◽  
pp. 1220-1226 ◽  
Author(s):  
YU. N. PAVLENKO ◽  
V. N. DOBRIKOV ◽  
N. L. DOROSHKO ◽  
O. K. GORPINICH ◽  
T. A. KORZINA ◽  
...  
Keyword(s):  
Excitation Energy ◽  
Nuclear Reactions ◽  
Coulomb Field ◽  
Light Nuclei ◽  
Final State ◽  
Resonance Parameters ◽  
Decay Properties ◽  
Unbound States ◽  
Decay Threshold

The decay properties of nuclear unbound states formed in the reactions with three particles in the final state are reviewed. The modification of resonance parameters observed in these reactions and caused by the influence of the Coulomb field of accompanied particles is analyzed for the resonances with excitation energy near and far from the decay threshold.

Proposed Solutions to Achieve Nuclear Fusion

Engevista ◽  
2017 ◽  
Vol 19 (5) ◽  
pp. 1496
Author(s):  
Relly Victoria Virgil Petrescu ◽  
Raffaella Aversa ◽  
Antonio Apicella ◽  
Florian Ion Petrescu
Keyword(s):  
Nuclear Reactor ◽  
Nuclear Reactions ◽  
Nuclear Fusion ◽  
Nuclear Fission ◽  
Light Nuclei ◽  
Fast Neutrons ◽  
Fusion Reactions ◽  
Nuclear Fusion Reactions ◽  
The Masses ◽  
Fusion Products

Despite research carried out around the world since the 1950s, no industrial application of fusion to energy production has yet succeeded, apart from nuclear weapons with the H-bomb, since this application does not aims at containing and controlling the reaction produced. There are, however, some other less mediated uses, such as neutron generators. The fusion of light nuclei releases enormous amounts of energy from the attraction between the nucleons due to the strong interaction (nuclear binding energy). Fusion it is with nuclear fission one of the two main types of nuclear reactions applied. The mass of the new atom obtained by the fusion is less than the sum of the masses of the two light atoms. In the process of fusion, part of the mass is transformed into energy in its simplest form: heat. This loss is explained by the Einstein known formula E=mc2. Unlike nuclear fission, the fusion products themselves (mainly helium 4) are not radioactive, but when the reaction is used to emit fast neutrons, they can transform the nuclei that capture them into isotopes that some of them can be radioactive. In order to be able to start and to be maintained with the success the nuclear fusion reactions, it is first necessary to know all this reactions very well. This means that it is necessary to know both the main reactions that may take place in a nuclear reactor and their sense and effects. The main aim is to choose and coupling the most convenient reactions, forcing by technical means for their production in the reactor. Taking into account that there are a multitude of possible variants, it is necessary to consider in advance the solutions that we consider them optimal. The paper takes into account both variants of nuclear fusion, and cold and hot. For each variant will be mentioned the minimum necessary specifications.

DEGENERATING CLUSTERS IN AN UNBOUND REGION OF 12Be

2009 ◽  
Vol 24 (11) ◽  
pp. 2175-2182 ◽  
Author(s):  
MAKOTO ITO
Keyword(s):  
Excitation Energy ◽  
Single Particle ◽  
Cluster Model ◽  
Particle Decay ◽  
Decay Threshold

The generalized two-center cluster model (GTCM), which can treat various single particle configurations in general two center systems, is applied to the light neutron-rich system, 12 Be = α+α+4N. We discuss the change of the neutrons' configuration around two α-cores as a variation of an excitation energy. We found that the covalent, ionic and atomic configurations appear with a prominent degenerating feature above the α+8 He g.s. particle-decay threshold.

EFFECT OF NEGATIVELY-CHARGED MASSIVE PARTICLES ON BIG-BANG NUCLEOSYNTHESIS AND A SOLUTION TO THE LITHIUM PROBLEMS

2008 ◽  
Vol 23 (17n20) ◽  
pp. 1668-1674
Author(s):  
MOTOHIKO KUSAKABE ◽  
TOSHITAKA KAJINO ◽  
RICHARD N. BOYD ◽  
TAKASHI YOSHIDA ◽  
GRANT J. MATHEWS
Keyword(s):  
Charged Particle ◽  
Nuclear Reactions ◽  
Charged Particles ◽  
Big Bang ◽  
Light Nuclei ◽  
Big Bang Nucleosynthesis ◽  
Spectroscopic Observations ◽  
Halo Stars ◽  
Wmap Data ◽  
Ionization Processes

Spectroscopic observations of metal poor halo stars give an indication of a possible primordial plateau of 6 Li abundance as a function of metallicity similar to that for 7 Li . The inferred abundance of 6 Li is ~1000 times larger than that predicted by standard big bang nucleosynthesis (BBN) for the baryon-to-photon ratio inferred from the WMAP data, and that of 7 Li is about 3 times smaller than the prediction. We study a possible solution to both the problems of underproduction of 6 Li and overproduction of 7 Li in BBN. This solution involves a hypothetical massive, negatively-charged particle that would bind to the light nuclei produced in BBN. The particle gets bound to the existing nuclei after the usual BBN, and a second epoch of nucleosynthesis can occur among nuclei bound to the particles. We numerically carry out a fully dynamical BBN calculation, simultaneously solving the recombination and ionization processes of negatively-charged particles by normal and particle-bound nuclei as well as many possible nuclear reactions among them. It is confirmed that BBN in the presence of these hypothetical particles can solve the two Li abundance problems simultaneously.

scholarly journals The pre-equilibrium and equilibrium double differential cross sections for the nucleons and light nuclei induce nuclear reactions on 27Al nuclei

2019 ◽  
Vol 15 (32) ◽  
pp. 77-91
Author(s):  
Maha Taha Idrees
Keyword(s):  
Cross Sections ◽  
Differential Cross ◽  
Nuclear Reactions ◽  
State Density ◽  
Light Nuclei ◽  
Hole State ◽  
Differential Cross Sections ◽  
Mass System ◽  
Shell Effects ◽  
27Al Target

The pre - equilibrium and equilibrium double differential crosssections are calculated at different energies using Kalbach Systematicapproach in terms of Exciton model with Feshbach, Kerman andKoonin (FKK) statistical theory. The angular distribution of nucleonsand light nuclei on 27Al target nuclei, at emission energy in the centerof mass system, are considered, using the Multistep Compound(MSC) and Multistep Direct (MSD) reactions. The two-componentexciton model with different corrections have been implemented incalculating the particle-hole state density towards calculating thetransition rates of the possible reactions and follow up the calculationthe differential cross-sections, that include MSC and MSD models.The finite well depth, isospin, shell effects, Pauli effect, chargeeffect, pairing, surface, angular and linear momentum distributionscorrections are considered in this work. The nucleons (n and p) andlight nuclei (2D and 3T) have been employed as projectiles at thetarget 27Al nuclei and at different incident energies (4MeV, 14 MeVand 14.8MeV). The results have been compared with the availableexperimental and theoretical published work. The comparisons showan acceptable agreement with the TALAYS code (Tendel 2014) forthe reactions: 27Al (n, n) 27Al, 27Al (p, n) 63Zn, 27Al (p, D) 62Cu, 27Al(p, p) 63Cu and 27Al (p, 4He)60Ni and at different emission energiesand angles.

scholarly journals Electronically driven neutrons synthesis-generator with the magneto-optical flow seal

2019 ◽  
Vol 222 ◽  
pp. 02014
Author(s):  
Mikhail Dolgopolov ◽  
Albina Gurskaya ◽  
Andrey Privalov ◽  
Vitaly Radenko ◽  
Alexandr Radenko ◽  
...  
Keyword(s):  
Multiphase Flow ◽  
Optical Flow ◽  
Neutron Generator ◽  
Nuclear Reactions ◽  
Theoretical Description ◽  
Light Nuclei ◽  
Plasma Target

We develop the description of a neutron generator construction for the synthesis of light nuclei. The design of the neutron generator with plasma target is given together with a description of the types of nuclear reactions that are implemented in it. The brief theoretical description of the ion multiphase flow in the synthesis generator is considered.

scholarly journals Applications of Nuclear Techniques, Computer Simulation and Microscopy to Depth Profiling of Light Nuclei

2012 ◽  
Vol 18 (S5) ◽  
pp. 83-84
Author(s):  
J. Pacheco de Carvalho ◽  
C. F. R. Pacheco ◽  
A. D. Reis
Keyword(s):  
Nuclear Reactions ◽  
Ion Beam ◽  
Depth Profiling ◽  
Light Nuclei ◽  
Analysis Method ◽  
Target Composition ◽  
Nuclear Techniques ◽  
Surface Analysis Techniques ◽  
Wide Range ◽  
Non Destructive

There is a wide range of surface analysis techniques which are, generally, complementary and provide target information for depths near the surface. Nuclear techniques, which are non-destructive, provide for analysis over a few microns close to the surface giving absolute values of concentrations of isotopes and elements. They have been applied in areas such as scientific, technologic, industry, arts and medicine, using MeV ion beams. Nuclear reactions permit tracing of isotopes with high sensitivities. We use ion-ion reactions and the energy analysis method. At a suitable energy of the incident ion beam, an energy spectrum is recorded of ions from the reaction, coming from several depths in the target. Such spectra are computationally predicted, giving target composition and concentration profile information. Elastic scattering is a particular and important case. A computer program has been developed in this context, mainly for flat targets. The non-flat target situation arises as an extension.

LEVEL DENSITIES IN LIGHTER NUCLEI

1965 ◽  
Vol 43 (7) ◽  
pp. 1248-1258 ◽  
Author(s):  
A. Gilbert ◽  
F. S. Chen ◽  
A. G. W. Cameron
Keyword(s):  
Excitation Energy ◽  
Ground State ◽  
Shell Structure ◽  
Mass Number ◽  
State Energy ◽  
Binding Energies ◽  
Light Nuclei ◽  
Cumulative Number ◽  
Additional Consideration ◽  
Level Densities

There has been discussion in the literature as to whether the cumulative number of levels in light nuclei varies more nearly as exp(const. [Formula: see text]) or exp(const. E), where E is the excitation energy. The question is examined in this paper. It is found that if one constructs "step diagrams" by plotting the cumulative number versus the energy, both formulas represent the data almost equally well. However, additional consideration of levels counted above neutron and proton binding energies shows that exp(const. [Formula: see text]) fails badly to represent the data, whereas exp(const. E) continues to give good fits. In either case E may be measured above an arbitrary ground-state energy E0. If the satisfactory formula is written in the form exp(E–E0)/T, then it is found that the dependence of the slope on mass number may be expressed in approximately the form T−1 = 0.0165A MeV−1, but there are significant deviations from this relation apparently related to shell structure. The intercepts E0 are quite variable but are roughly clustered according to the oddness or evenness of the neutron and proton numbers of the nucleus.

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