Evolution of Nuclear Shapes in Light Nuclei from Proton- to Neutron-rich Side

The presence of alpha cluster structures in light nuclei is well established. This paper concentrates on the medium light nuclei between 16 O and 44 Ti . Especially the nucleus 32 S has been examined in detail and new data is presented. The elastic scattering data of alpha particles on 28 Si forming 32 S shows a peculiar disappearance of cross section at 31 MeV excitation energy and above. Also, the energy versus J(J + 1) plot shows at least one clear rotational-like band of alpha cluster states, with the main energy levels split into many narrow and closely lying levels with the same spin. Furthermore, few experiments have been carried out investigating the alpha cluster structure of non-nα nuclei, especially on the proton rich side of stability. The evidence at hand indicates that adding neutrons retains some alpha cluster structures and in some cases might even enhance them, but adding protons seems to destroy the structures.

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Proposed Solutions to Achieve Nuclear Fusion

Engevista ◽

10.22409/engevista.v19i5.968 ◽

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.

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Nuclear Electrons and Nuclear Structure

10.1093/oso/9780198827870.003.0006 ◽

2018 ◽

Author(s):

Roger H. Stuewer

Keyword(s):

Nuclear Structure ◽

Beta Decay ◽

Gamma Rays ◽

Alpha Particle ◽

Continuous Distribution ◽

Alpha Particles ◽

Light Nuclei ◽

Coincidence Method ◽

Wolfgang Pauli ◽

Beta Particles

Serious contradictions to the existence of electrons in nuclei impinged in one way or another on the theory of beta decay and became acute when Charles Ellis and William Wooster proved, in an experimental tour de force in 1927, that beta particles are emitted from a radioactive nucleus with a continuous distribution of energies. Bohr concluded that energy is not conserved in the nucleus, an idea that Wolfgang Pauli vigorously opposed. Another puzzle arose in alpha-particle experiments. Walther Bothe and his co-workers used his coincidence method in 1928–30 and concluded that energetic gamma rays are produced when polonium alpha particles bombard beryllium and other light nuclei. That stimulated Frédéric Joliot and Irène Curie to carry out related experiments. These experimental results were thoroughly discussed at a conference that Enrico Fermi organized in Rome in October 1931, whose proceedings included the first publication of Pauli’s neutrino hypothesis.

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