No description available.

This thesis describes the development of computer programs and the theory for the calculations of stopping power and nuclear reaction kinematics. The nuclear reaction kinematics program computes position and nonrelativistic energy data as well as center-of-mass solid angle transformations and information on detector resolution for nuclear reactions and elastic scattering experiments involving two-body final states. The stopping power program calculates stopping power (an index of the charged particle energy absorption properties of a material) of elemental absorbers for protons, deuterons, tritons, He3, and alpha particles from minimal input data. The calculated stopping powers are accurate to within one per cent over the nonrelativistic energy range of 2 to 12 Mev.Ball State UniversityMuncie, IN 47306

The identification of stopping charged particles in G.5 nuclear emulsion by using a residual range ionization method has been investigated in this experiment using a large stack of ILFord, G.5 nuclear emulsion pellicles exposed to 450 and 435 Me V/c K ˉ mesons at the Berkeley Bevatron.The restricted rate of energy loss vs kinetic energy for protons has been calculated theoretically, and given in Barkas(9). Then for given values of B , we calculated the restricted rate of energy loss vs the kinetic energy of muon, pion, kaon, and sigma particles.The measurement of the residual range and the counting of blobs in each residual range segment were carried out for four known stopping pions tracks. A second degree polynomial computer fit program was used to interpret the plot of residual range vs blobs/100 μ m. Then a particular point on the plot was chosen as a reference for normalizing the relative grain density (g*), theoretically and experimentally. Next, theoretical tables of residual range (R) vs relative grain density (g*theo) were calculated for muons, pions, kaons, protons, and sigmas. Those portions of the latter tables, for which (g*theo) was less than - 2, were used for the above mentioned theoretical plot of residual range (R) vs relative grain density (g* theo). The theoretically predicted curves were then tested by experimentally measuring the residual range and counting the blobs of each range segment of two selected stopping particle (primary) tracks which we suspected to be stopping kaon tracks. Then the second degree polynomial computer fit to the plotted data of the measured residual range vs blobs/l00 μm was carried out for each of the two suspected stopping kaon particles. Three points from each curve were picked and superimposed on the theoretical curves. The results were good but showed that it is necessary to measure a sufficiently long residual range, and more than one segment of blob-counts should be used along the measured residual range for accurate identification of the given particle.Ball State UniversityMuncie, IN 47306

No description available.

Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (leaves [112]-119).

A perda de energia de íons na matéria é um tópico de grande interesse não apenas por suas aplicações diretas em técnicas de análises de materiais bem como nos estudos teóricos das interações íon-átomo. No entanto, o poder de freamento de sólidos para íons pesados é ainda pouco compreendido especialmente para baixas velocidades devido principalmente a complicada dependência nos números atômicos do meio freador e do íon incidente. Neste trabalho são apresentados os dados experimentais para o freamento de Cu em Au na região de velocidades de 2 - 4% da velocidade da luz. Os dados experimentais foram obtidos com uso da técnica de espalhamento elástico, onde um feixe primário de 16O e 28Si, com energias entre 35 - 52 MeV e 49 - 79 MeV respectivamente, foram tilizados para produzir íons de Cu em recuo a partir de um alvo fino ( 160 g/cm2). O feixe primário espalhado é detectado a 60o por um detector de Si, produzindo átomos de Cu do alvo recuando em um ângulo denido pela cinemática da colisão elástica. Os íons em recuo medidos em coincidência temporal com o feixe primário espalhado compõe o feixe secundário de interesse. A perda de energia, em uma folha de Au com espessura em torno de 530 g/cm2, foi obtida medindo-se a energia do feixe secundário com um detector de Si, com e sem a folha de Au interceptando os íons em recuo. Os dados experimentais foram comparados com teorias e modelos semi-empíricos aplicáveis a esse caso. Bom acordo entre a previsão da Aproximação de Convolução Unitária e nossos dados experimentais é observado. / The energy loss of ions in materials is an important issue not only because of its direct applications in analytic techniques of materials but also for studying the basics of ion-atom interactions. Nevertheless, the Stopping Power of heavy ions in solids is still poorly understood which is especially true at low velocities mainly due to the complicated dependence on the atomic numbers of the stopper medium and of the stopping ion. In this work we present new experimental data for Copper ions slowing down in Gold foil in the velocity range of 2 to 4% of the velocity of light. Experimental data were obtained using the elastic scattering technique, where primary beams of 16O and 28Si, with energies from 35 to 52 MeV and 49 to 79 MeV respectively, were used to scatter Cu íons from a thin target ( 160 g/cm2). The scattered primary beam is detected at 60 with a Si detector, producing recoiling atoms of the target in an angle given by the elastic scattering kinematics. The recoiling ions in temporal coincidence with the scattered primary beam will compose the secondary beam. The energy loss, in a gold foil with thickness about 530 g/cm2, was obtained by measuring the energy of the secondary beam with a Si detector, with and without the Au foil intercepting the recoiling ions. Experimental results were compared with theories and semi-empirical models applied to this case. Good agreement between Unitary Convolution Approximation (UCA) prediction and our data is observed.

A perda de energia de íons na matéria é um tópico de grande interesse não apenas por suas aplicações diretas em técnicas de análises de materiais bem como nos estudos teóricos das interações íon-átomo. No entanto, o poder de freamento de sólidos para íons pesados é ainda pouco compreendido especialmente para baixas velocidades devido principalmente a complicada dependência nos números atômicos do meio freador e do íon incidente. Neste trabalho são apresentados os dados experimentais para o freamento de Cu em Au na região de velocidades de 2 - 4% da velocidade da luz. Os dados experimentais foram obtidos com uso da técnica de espalhamento elástico, onde um feixe primário de 16O e 28Si, com energias entre 35 - 52 MeV e 49 - 79 MeV respectivamente, foram tilizados para produzir íons de Cu em recuo a partir de um alvo fino ( 160 g/cm2). O feixe primário espalhado é detectado a 60o por um detector de Si, produzindo átomos de Cu do alvo recuando em um ângulo denido pela cinemática da colisão elástica. Os íons em recuo medidos em coincidência temporal com o feixe primário espalhado compõe o feixe secundário de interesse. A perda de energia, em uma folha de Au com espessura em torno de 530 g/cm2, foi obtida medindo-se a energia do feixe secundário com um detector de Si, com e sem a folha de Au interceptando os íons em recuo. Os dados experimentais foram comparados com teorias e modelos semi-empíricos aplicáveis a esse caso. Bom acordo entre a previsão da Aproximação de Convolução Unitária e nossos dados experimentais é observado. / The energy loss of ions in materials is an important issue not only because of its direct applications in analytic techniques of materials but also for studying the basics of ion-atom interactions. Nevertheless, the Stopping Power of heavy ions in solids is still poorly understood which is especially true at low velocities mainly due to the complicated dependence on the atomic numbers of the stopper medium and of the stopping ion. In this work we present new experimental data for Copper ions slowing down in Gold foil in the velocity range of 2 to 4% of the velocity of light. Experimental data were obtained using the elastic scattering technique, where primary beams of 16O and 28Si, with energies from 35 to 52 MeV and 49 to 79 MeV respectively, were used to scatter Cu íons from a thin target ( 160 g/cm2). The scattered primary beam is detected at 60 with a Si detector, producing recoiling atoms of the target in an angle given by the elastic scattering kinematics. The recoiling ions in temporal coincidence with the scattered primary beam will compose the secondary beam. The energy loss, in a gold foil with thickness about 530 g/cm2, was obtained by measuring the energy of the secondary beam with a Si detector, with and without the Au foil intercepting the recoiling ions. Experimental results were compared with theories and semi-empirical models applied to this case. Good agreement between Unitary Convolution Approximation (UCA) prediction and our data is observed.

The present work reports the experimental evidence of anomalous energy loss, energy straggling, and the corresponding ion-induced electron emission yields of channeled protons in silicon.

No description available.

Accurate knowledge of stopping powers is essential for these for quantitative analysis and surface characterization of thin films using ion beam analysis (IBA). These values are also of interest in radiobiology and radiotherapy, and in ion- implantation technology where shrinking feature sizes puts high demands on the accuracy of range calculations. A theory that predicts stopping powers and ranges for all projectile-target combinations is needed. The most important database used to report the stopping powers is the SRIM/TRIM program developed by Ziegler and coworkers. However, other researchers report that at times, these values differ significantly from experimental values. In this study the stopping powers of Si, P and S ions have been measured in Ni, Cu, Ge and GaAs absorbers in the energy range ~ 2-10 MeV. For elemental films of Ni, Cu and Ge, the stopping of heavy ions was measured using a novel ERD (Elastic Recoil Detection) based technique. In which an elastically recoiled lighter atom is used to indirectly measure the energy of the incoming heavy ion using a surface barrier detector. In this way it was possible to reduce the damage and to improve the FWHM of the detector. The results were compared to SRIM-2000 predictions and other experimental measurements. A new technique derived from Molecular Beam Epitaxy (MBE) was developed to prepare stoichiometric GaAs films on thin carbon films for use in transmission ion beam experiments. The GaAs films were characterized using X-ray Photoelectron Spectroscopy (XPS) and Particle Induced X-ray Emission (PIXE). These films were used to investigate the stopping powers of energetic heavy ions in GaAs and to provide data for the calculation of Bethe-Bloch parameters in the framework of the Modified Bethe-Bloch theory. As a result of this study, stopping power data are available for the first time for Si and P ions in the energy range 2-10 MeV stopping in GaAs absorbers.