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It is important that accurate estimates of crew exposure to radiation are obtained for future long - term space missions. To predict the radiation environment, a few space radiation transport codes exist, all of which use basic nuclear cross section information for transport of radiation through materials. Little theoretical and experimental work has been conducted on reactions induced by the electromagnetic (EM) force, especially with regard to di?erential cross sections. Therefore, radiation transport codes have typically neglected to incorporate EM nuclear collision cross sections. EM cross sections for single nucleon removal have been included in some radiation codes, but better values can be obtained by using an energy dependent branching ratio. Most previous theoretical and experimental work has been devoted to total cross sections. Therefore, the energy dependent branching ratios presented can be extensively compared to past theory and experiment. Such comparisons indicate that using energy dependent branching ratios yield better estimates of total cross sections. Differential cross sections for electromagnetic dissociation in nuclear collisions are calculated for the first time. In order to be useful for three - dimensional transport codes, these cross sections have been calculated in both the projectile and lab frames. The formulas for these cross sections are such that they can be immediately used in space radiation transport codes. Only a limited amount of data exists, but the comparison between theory and experiment is good.

Lau, Yuk Yeung = 重離子核聚變驅動設備的最終壓縮離子束線系統 / 劉鈺暘. / "November 2011." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (p. 99-101). / Abstracts in English and Chinese. / Lau, Yuk Yeung = Zhong li zi he ju bian qu dong she bei de zui zhong ya suo li zi shu xian xi tong / Liu Yuyang. / Abstract --- p.i / 概要 --- p.iii / Acknowledgements --- p.iv / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Background --- p.5 / Chapter 2.1 --- Nuclear fusion --- p.5 / Chapter 2.1.1 --- Nuclear fusion as an energy source --- p.5 / Chapter 2.1.2 --- Lawson criterion --- p.7 / Chapter 2.1.3 --- Confinement method --- p.8 / Chapter 2.2 --- Inertial confinement fusion --- p.11 / Chapter 2.2.1 --- Driving beams --- p.11 / Chapter 2.2.2 --- Reactor chamber --- p.14 / Chapter 2.2.3 --- Ignition target --- p.14 / Chapter 2.3 --- Heavy ion inertial confinement fusion --- p.16 / Chapter 2.3.1 --- Beam source and accelerator system --- p.18 / Chapter 2.3.2 --- Drift compression section --- p.20 / Chapter 2.4 --- Beam dynamics --- p.23 / Chapter 2.4.1 --- Transverse dynamics --- p.24 / Chapter 2.4.2 --- Longitudinal dynamics --- p.26 / Chapter 2.4.3 --- Emittance --- p.27 / Chapter 2.5 --- Simulation codes --- p.28 / Chapter 2.5.1 --- Particle in cell simulation --- p.28 / Chapter 2.5.2 --- WARP code --- p.29 / Chapter 3 --- Drift compression beamline system for heavy ion fusion drivers --- p.31 / Chapter 3.1 --- Beam requirements for target implosion in HIF driver --- p.31 / Chapter 3.2 --- Drift compression beamline configuration --- p.33 / Chapter 3.3 --- Simulation example --- p.39 / Chapter 3.4 --- Minimization of centroid offset with bend strategies --- p.42 / Chapter 3.5 --- Neutralized drift section and final focusing --- p.50 / Chapter 3.6 --- "Final pulse length, spot size and emittance" --- p.52 / Chapter 4 --- Longitudinal emittance growth due to non-linear space charge effects --- p.61 / Chapter 4.1 --- Longitudinal emittance growth in the linear regime - Simulation results --- p.62 / Chapter 4.2 --- Longitudinal emittance growth in the linear regime - analytical results --- p.67 / Chapter 4.2.1 --- Beam with uniform radius --- p.68 / Chapter 4.2.2 --- Beam with uniform density --- p.73 / Chapter 4.2.3 --- Comparison with simulations --- p.76 / Chapter 4.2.4 --- Extension to more general beams --- p.78 / Chapter 4.3 --- Longitudinal emittance evolution in the nonlinear regime --- p.79 / Chapter 4.4 --- Target pulse length minimization --- p.86 / Chapter 4.4.1 --- Optimization of drift compression beamline and beam parameters --- p.86 / Chapter 4.4.2 --- Phase space correction with initial voltage waveform tailoring --- p.90 / Chapter 4.5 --- Coupling of Longitudinal and Transverse Emittances --- p.91 / Chapter 5 --- Summary --- p.95 / Bibliography --- p.99

Multifragmentation reactions have been used to study many of the complexities of the nucleus. Recently, work has been done to tie observables from multifragmentation reactions to astrophysical observables used in supernova explosions. To make this connection, it is necessary to have a highly excited, equilibrated system. The creation of a highly excited system is done for this dissertation by the reaction of one projectile, ³²S, on three targets, ¹¹²⁾¹²⁴Sn and ^natAu at 45 MeV/nucleon. The forward array using silicon technology, FAUST, was used to collect the fragments produced from the excited projectiles. The motivation for this study was to isotopically identify the fragmenting source and to understand the relationship between its N/Z and the resulting fragmentation. This can then be used to constrain theoretical models which predict the evolution of supernova explosions. Using an isotropically identified source, the resulting fragmentation of the projectile has been studied. It is shown that there are dependencies on the fragment mass distribution, fragment charge distribution and source excitation energy from the source N/Z. Looking more specifically at the fragments produced, it was found that there is a parallel velocity anisotropy in the particle emission. This anisotropy is found to be a direct result of the presence of an external Coulomb field. Using DIT+SMM theoretical calculations, the anisotropy has been found to be dependent on the distance at which the projectile breaks up from the target (external Coulomb field). As the parallel velocity is related to the angle of emission, it is of interest to extract out the average kinetic energy of each isotope to determine if there are differences in the average kinetic energy by the angle of emission. It is found that the average kinetic energy is dependent on the emission angle in the quasi-projectile frame. Because of this, care should be taken when comparing between systems to ensure similar regions are being compared. However, the observation that the average kinetic energy changes as a function of the emission angle is not dependent on the presence of an external Coulomb field. Using DIT+SMM calculations, the differences between the average kinetic energy from different angles of emission are seen even when no external Coulomb field is present. These changes are attributed to the angular momentum. In all cases, a statistical framework, supplied by DIT+SMM calculations, can explain many phenomena seen from a fragmenting nucleus. However, the accuracy of the model varies when moving from a neutron-poor to a neutron-rich source.

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