Дисертації: "Nuclear physics"

1

Alhomaidhi, Sultan Mohammad A. "Search for Maximum Nuclear Compression in a Model of Nucleus-Nucleus Collisions." Kent State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=kent1448216380.

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2

Chen, Jiunn-Wei. "Effective field theory for nuclear physics /." Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/9795.

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3

Persram, Declan. "Delta production in nucleon-nucleon scattering and pion production in nucleus-nucleus collisions." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23931.

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We present a calculation of $ Delta$ production cross section in the one-boson-exchange model for the reaction $NN to N Delta.$ Our calculation is in quantitative agreement with a previous calculation by Huber and Aichelin (1). The effect of the $NN to N Delta$ anisotropic differential cross section on $ pi$ production in Au + Au collisions at a kinetic energy of $1{GeV over A}$ is studied. We find that there is no large effect on the final $ pi$ transverse momentum spectra.

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4

Ramanan, Sunethra. "Investigations of the renormalization group approach to the nucleon-nucleon interaction." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1173106852.

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5

Bemmerer, Daniel. "Precise nuclear physics for the Sun." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-95439.

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For many centuries, the study of the Sun has been an important testbed for understanding stars that are further away. One of the first astronomical observations Galileo Galilei made in 1612 with the newly invented telescope concerned the sunspots, and in 1814, Joseph von Fraunhofer employed his new spectroscope to discover the absorption lines in the solar spectrum that are now named after him. Even though more refined and new modes of observation are now available than in the days of Galileo and Fraunhofer, the study of the Sun is still high on the agenda of contemporary science, due to three guiding interests. The first is connected to the ages-old human striving to understand the structure of the larger world surrounding us. Modern telescopes, some of them even based outside the Earth’s atmosphere in space, have succeeded in observing astronomical objects that are billions of light- years away. However, for practical reasons precision data that are important for understanding stars can still only be gained from the Sun. In a sense, the observations of far-away astronomical objects thus call for a more precise study of the closeby, of the Sun, for their interpretation. The second interest stems from the human desire to understand the essence of the world, in particular the elementary particles of which it consists. Large accelerators have been constructed to produce and collide these particles. However, man-made machines can never be as luminous as the Sun when it comes to producing particles. Solar neutrinos have thus served not only as an astronomical tool to understand the Sun’s inner workings, but their behavior on the way from the Sun to the Earth is also being studied with the aim to understand their nature and interactions. The third interest is strictly connected to life on Earth. A multitude of research has shown that even relatively slight changes in the Earth’s climate may strongly affect the living conditions in a number of densely populated areas, mainly near the ocean shore and in arid regions. Thus, great effort is expended on the study of greenhouse gases in the Earth’s atmosphere. Also the Sun, via the solar irradiance and via the effects of the so-called solar wind of magnetic particles on the Earth’s atmosphere, may affect the climate. There is no proof linking solar effects to short-term changes in the Earth’s climate. However, such effects cannot be excluded, either, making it necessary to study the Sun. The experiments summarized in the present work contribute to the present-day study of our Sun by repeating, in the laboratory, some of the nuclear processes that take place in the core of the Sun. They aim to improve the precision of the nuclear cross section data that lay the foundation of the model of the nuclear reactions generating energy and producing neutrinos in the Sun. In order to reach this goal, low-energy nuclear physics experiments are performed. Wherever possible, the data are taken in a low-background, underground environment. There is only one underground accelerator facility in the world, the Laboratory Underground for Nuclear Astro- physics (LUNA) 0.4 MV accelerator in the Gran Sasso laboratory in Italy. Much of the research described here is based on experiments at LUNA. Background and feasibility studies shown here lay the base for future, higher-energy underground accelerators. Finally, it is shown that such a device can even be placed in a shallow-underground facility such as the Dresden Felsenkeller without great loss of sensitivity.

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6

Bemmerer, Daniel. "Precise nuclear physics for the sun." Forschungszentrum Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-97364.

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For many centuries, the study of the Sun has been an important testbed for understanding stars that are further away. One of the first astronomical observations Galileo Galilei made in 1612 with the newly invented telescope concerned the sunspots, and in 1814, Joseph von Fraunhofer employed his new spectroscope to discover the absorption lines in the solar spectrum that are now named after him. Even though more refined and new modes of observation are now available than in the days of Galileo and Fraunhofer, the study of the Sun is still high on the agenda of contemporary science, due to three guiding interests. The first is connected to the ages-old human striving to understand the structure of the larger world surrounding us. Modern telescopes, some of them even based outside the Earth’s atmosphere in space, have succeeded in observing astronomical objects that are billions of lightyears away. However, for practical reasons precision data that are important for understanding stars can still only be gained from the Sun. In a sense, the observations of far-away astronomical objects thus call for a more precise study of the closeby, of the Sun, for their interpretation. The second interest stems from the human desire to understand the essence of the world, in particular the elementary particles of which it consists. Large accelerators have been constructed to produce and collide these particles. However, man-made machines can never be as luminous as the Sun when it comes to producing particles. Solar neutrinos have thus served not only as an astronomical tool to understand the Sun’s inner workings, but their behavior on the way from the Sun to the Earth is also being studied with the aim to understand their nature and interactions. The third interest is strictly connected to life on Earth. A multitude of research has shown that even relatively slight changes in the Earth’s climate may strongly affect the living conditions in a number of densely populated areas, mainly near the ocean shore and in arid regions. Thus, great effort is expended on the study of greenhouse gases in the Earth’s atmosphere. Also the Sun, via the solar irradiance and via the effects of the so-called solar wind of magnetic particles on the Earth’s atmosphere, may affect the climate. There is no proof linking solar effects to short-term changes in the Earth’s climate. However, such effects cannot be excluded, either, making it necessary to study the Sun. The experiments summarized in the present work contribute to the present-day study of our Sun by repeating, in the laboratory, some of the nuclear processes that take place in the core of the Sun. They aim to improve the precision of the nuclear cross section data that lay the foundation of the model of the nuclear reactions generating energy and producing neutrinos in the Sun. In order to reach this goal, low-energy nuclear physics experiments are performed. Wherever possible, the data are taken in a low-background, underground environment. There is only one underground accelerator facility in the world, the Laboratory Underground for Nuclear Astrophysics (LUNA) 0.4MV accelerator in the Gran Sasso laboratory in Italy. Much of the research described here is based on experiments at LUNA. Background and feasibility studies shown here lay the base for future, higher-energy underground accelerators. Finally, it is shown that such a device can even be placed in a shallow-underground facility such as the Dresden Felsenkeller without great loss of sensitivity.

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7

Konig, Sebastian, Harald W. Griesshammer, H. W. Hammer, and Kolck U. van. "Nuclear Physics Around the Unitarity Limit." AMER PHYSICAL SOC, 2017. http://hdl.handle.net/10150/624335.

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We argue that many features of the structure of nuclei emerge from a strictly perturbative expansion around the unitarity limit, where the two-nucleon S waves have bound states at zero energy. In this limit, the gross features of states in the nuclear chart are correlated to only one dimensionful parameter, which is related to the breaking of scale invariance to a discrete scaling symmetry and set by the triton binding energy. Observables are moved to their physical values by small perturbative corrections, much like in descriptions of the fine structure of atomic spectra. We provide evidence in favor of the conjecture that light, and possibly heavier, nuclei are bound weakly enough to be insensitive to the details of the interactions but strongly enough to be insensitive to the exact size of the two-nucleon system.

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8

Medinaceli, Villegas Eduardo <1976&gt. "Astroparticle physics with nuclear track detectors." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/850/1/Tesi_Medinaceli_Eduardo.pdf.

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This thesis is mainly about the search for exotic heavy particles -Intermediate Mass Magnetic Monopoles, Nuclearites and Q-balls with the SLIM experiment at the Chacaltaya High Altitude Laboratory (5230 m, Bolivia), establishing upper limits (90% CL) in the absence of candidates, which are among the best if not the only one for all three kind of particles. A preliminary study of the background induced by cosmic neutron in CR39 at the SLIM site, using Monte Carlo simulations. The measurement of the elemental abundance of the primary cosmic ray with the CAKE experiment on board of a stratospherical balloon; the charge distribution obtained spans in the range 5≤Z≤31. Both experiments were based on the use of plastic Nuclear Track Detectors, which records the passage of ionizing particles; by using some chemical reagents such passage can be make visible at optical microscopes.

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9

Medinaceli, Villegas Eduardo <1976&gt. "Astroparticle physics with nuclear track detectors." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/850/.

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This thesis is mainly about the search for exotic heavy particles -Intermediate Mass Magnetic Monopoles, Nuclearites and Q-balls with the SLIM experiment at the Chacaltaya High Altitude Laboratory (5230 m, Bolivia), establishing upper limits (90% CL) in the absence of candidates, which are among the best if not the only one for all three kind of particles. A preliminary study of the background induced by cosmic neutron in CR39 at the SLIM site, using Monte Carlo simulations. The measurement of the elemental abundance of the primary cosmic ray with the CAKE experiment on board of a stratospherical balloon; the charge distribution obtained spans in the range 5≤Z≤31. Both experiments were based on the use of plastic Nuclear Track Detectors, which records the passage of ionizing particles; by using some chemical reagents such passage can be make visible at optical microscopes.

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10

Alsalmi, Sheren. "Measurement of the Nuclear Dependence of F_2 and R=Sigma_L/Sigma_T in The Nucleon Resonance Region." Kent State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=kent155655860740778.

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11

Shi, Junhui. "Nuclear spin optical rotation in organic liquids." Thesis, Princeton University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3604505.

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Nuclear spin induced optical rotation (NSOR) is a novel technique for the detection of nuclear magnetic resonance (NMR) via optical rotation instead of conventional pick-up coil. Originating from hyperfine interactions between nuclei and orbital electrons, NSOR provides a new method to reveal nuclear chemical environments in different molecules. Previous experiments of NSOR detection have poor signal-to-noise ratio (SNR), which limits the application of NSOR in chemistry. In this work, based on a continuous-wave NMR scheme at a low magnetic field (5 G), we employ a multi-pass cavity and a 405 nm laser to improve the sensitivity of NSOR. By performing precision measurements of NSOR detection in a range of pure liquid organic chemicals, we demonstrate the capability of NSOR to distinguish 1H signals in different chemicals, in agreement with the first-principles quantum mechanical calculations. The NSOR of 19F is also measured at low fields with high SNR, showing that heavy nuclei have higher optical rotation signals than light nuclei.

In addition, in order to obtain NSOR at different chemical sites in the same molecule via chemical shift, we make efforts to develop a novel scheme based on liquid-core hollow fiber for the detection of NSOR under high magnetic fields. By coiling a long liquid-core fiber densely for many loops around a small rod combined with RF coils, it is possible to measure optical rotation signals inside a narrow-bore superconducting magnet. Manufactured by filling liquids into capillary tubings, those liquid-core fibers perform like multimode step-index fibers, and thereby exhibit linear birefringence and depolarization, significantly reducing the light polarization for the measurement of optical rotation. According to our attempts, it is possible to suppress the linear birefringence by filling chiral liquids in hollow fibers, and approach near single-mode operation by means of launching light beam into the fiber core under the mode match condition. Although some issues of hollow fibers obstruct the final measurement of high-frequency NSOR, our work on the liquid-core fiber provides the basis for future fiber-based NSOR experiments under high magnetic fields.

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12

Seely, Jason (Charles Jason). "Precise measurement of the nuclear dependence of structure functions in light nuclei." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/39559.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2006.
Includes bibliographical references (leaves 171-174).
The EMC effect has been with us for over 20 years. During this time, the nuclear dependence of the structure functions, and therefore the underlying quark distributions, has been studied with much success. However, the bulk of the experimental effort has been to measure the effect in heavy nuclei where it has the same zBj dependence and differs only in magnitude. Calculations predict large differences in both the magnitude and zBj-dependence of the EMC effect in 3He and 4He and precise measurements of the EMC effect in these nuclei could be used to distinguish between existing models. E03-103 measured the inclusive electron scattering cross-section on 1H, 2H, 3He, and 4He, as well as the heavier targets Be, C, Cu, and Au. This thesis describes the experiment in detail and presents results for 3He, 4He, and carbon. These data provide the first measurement of the EMC effect in 3He above xBj > 0.4, and improve upon the existing measurement of the effect in 4He.
by Jason Seely.
Ph.D.

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13

Minkov, Ivaylo. "Theoretical studies of X-ray induced nuclear dynamics." Licentiate thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-296.

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14

Norrick, Anne. "A Measurement of Nuclear Effects in Deep Inelastic Scattering in Neutrino-Nucleus Interactions." W&M ScholarWorks, 2018. https://scholarworks.wm.edu/etd/1550153893.

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Neutrino-Nucleus Deep Inelastic Scattering (DIS) events provide a probe into the structure of nucleons within a nucleus that cannot be accessed via charged lepton-nucleus interactions. The MINERvA experiment is stationed in the Neutrinos from the Main Injector (NuMI) beam line at Fermi National Accelerator Laboratory. With the recent increase in average neutrino energy and the greatly increased intensity of the NuMI beam line, projected sensitivities for DIS cross section ratio analyses using MINERvA's suite of nuclear targets (C, CH, Fe and Pb) are greatly increased. an analysis of theMINERvA DIS data on carbon, iron, lead, and plastic has been conducted for muon neutrino interactions with a muon angle less than 17 degrees. Results are presented as a differential cross section with respect to neutrino energy and the Bjorken-x scaling variable.

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15

Jansson, Peter. "Studies of Nuclear fuel by means of Nuclear Spectroscopy Methods." Licentiate thesis, Uppsala universitet, Institutionen för kärn- och partikelfysik, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-85900.

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This paper which is a thesis for the title teknologie licentiat is a summary text of several works performed by the author regarding spectroscopic measurements on spent nuclear fuel. Methods for determining the decay heat of spent nuclear fuel by means of gammaray spectroscopy and for verifying the integrity of nuclear fuel by means of tomography is presented. A summary of work performed regarding gammaray detector technology for studies of fission gas release is presented.

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16

Marsden, David Charles. "An investigation of the Tucson-Melbourne three-nucleon force in the nuclear many-body problem." Diss., The University of Arizona, 2002. http://hdl.handle.net/10150/289793.

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The no-core shell-model approach has proven to be extremely useful for the theoretical determination of the properties of light (A ≤ 12) nuclei. However, at present this method does not accommodate a three-nucleon interaction into the potential that it employs. The problem is introduced with a largely historical development of both the effective interaction formalism and three-nucleon interactions, placing the motivation in context. This work makes a first attempt to incorporate such a three-nucleon interaction into the no-core shell-model ansatz. To this end, a variant of the two-pion-exchange Tucson-Melbourne three-nucleon interaction has been chosen. A three-body translationally-invariant harmonic-oscillator basis is constructed, and matrix elements of the three-nucleon interaction in this basis are calculated. The majority of this is accomplished through standard angular-momentum algebraic techniques, with the most expensive component being the spatial one, as it requires a transformation of the basis set with computationally intensive transformation brackets. Given the ability to determine the matrix elements for the chosen Tucson-Melbourne force, the practicality of employing these in calculations is demonstrated, with calculations on the three-body nuclei ³H and ³He. These are simple calculations, where the Tucson-Melbourne matrix elements are added to those of the two-body effective potential (a slight inconsistency which future studies will aim to fix). The dependence of binding energies on the harmonic-oscillator parameter, hΩ, and the Tucson-Melbourne cutoff parameter, Λ are examined. The former is found to be small in the range of hΩ considered, while the latter is shown to be consistent with previous works that have explored this dependence using other methods. The convergence of the binding energy with increasing model space size is slow, but this is perhaps attributable to the unrenormalized nature of the three-body matrix elements. The ultimate aim of this research is to find a viable method for constructing a three-body effective interaction from a given "realistic" three nucleon interaction, for use in no-core shell-model calculations. The current work demonstrates that such a scheme is feasible, and should yield results more consistent with experiment. Such a three-body effective interaction should also achieve quicker convergence with model space size than shown here, as the three-nucleon matrix elements will be renormalized to account for the geometry of the model space. Thus, one will have constructed an ab initio method for calculations on light nuclei, that includes a three-nucleon interaction, and converges quickly in the determination of nuclear properties.

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17

Damodaran, K. "Topological defects in cosmology and nuclear physics." Thesis, University of Cambridge, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.598261.

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This dissertation is concerned with topological defects that arise from symmetry breaking in the non-linear sigma model limits of scalar field theories. The nonlinear evolution of global topological defects in O (N) field theories provide a mechansims for sourcing hte cosmic microwave background (CMB) temperature anisotropy on the sky today. In these theories, N determines the type of defect based on the homotopy group of the underlying vacuum manifold. Additionally, in models of nuclear physics based on SU (2) gauge theories, π₃ defects can manifest themselves as static soliton solutions. A simple class of O (N) scalar fields are studied here. The defects considered were strings with N =2, monopoles with N =3, textures with N = 4 and a class of "non-topological" textures, with N =6. Calculations of the temperature anisotropy are computationally challenging. High precision is needed in order to cmopare predictions with new and future CMB observations. The anisotropy is calculated from the classic Sachs-Wolfe formula by using a real space evolution for the matter and radiatino fluids. In order to properly account for diffusion damping and the finnite thickness of the last scattering surface, the power spectra were compared to high precision calculations based on defect source stress energy tensor unequal-time correlators. Matching the tails of the spectra yielded an angualr smoothing scale l _D for the fluctuation maps. Ensembles of 10° maps of the sky today were produced for each defect. Defects also have implications in modesl of nucelar physics. The first π₃ soliton to be studied in nuclear physics was the Skyrmion, a topological solution to the nonlinear sigma model for pion fields. Skyrme introduced a four-derivative term to stabilize the soliton. Alternatively one could introduce gauge fields to stabilize the texture. It is shown that the presence of an extra identical Higgs doublet in a gauged SU (2) nonlinear sigma model can produce soliton solutions. The solution is related to the Sphaleron and Electroweak Skyrmion in the Standard Model, but unlike these solitons, it is dyanmically stable to small spherically symmetric perturbations. A similar solution is shown to exist in the Vector Dominance model, with p-mesons representing the gauge bosons of a hidden local SU (2) gauge symmetry of the nonlinear sigma model. This is in agreement with similar work done by Igarashi, Johmuar, Kobayashi, Otsu, Sato and Sawada.

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18

Kronenberg, Eric Leslie. "The eikonal expansion in electromagnetic nuclear physics." Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/14181.

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19

Chen, Cheng. "NUCLEAR QUADRUPLE RESONANCE AND LOW-FIELD NUCLEAR MAGNETIC RESONANCE FOR MATERIALS AUTHENTICATION." Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case1567518073598426.

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20

Dixon, Lisa. "Search for the Nuclear Barnett Effect." Thesis, New York University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3591197.

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Gyromagnetic phenomena have been of interest since the dawn of modern electromagnetic theory. While rotation-induced magnetization in electronic systems has been known for over 100 years, the phenomenon remains largely unexplored in nuclear degrees of freedom. This thesis explores the influence of external angular momentum on nuclear polarization, utilizing optical fields endowed with orbital angular momentum (OAM). To that end, I employ novel holographic methods to project light fields with programmable OAM content into fluid samples. To quantify the OAM in such fields, I introduce new techniques of holographic video microscopy to characterize optical forces. These optical manipulation and detection schemes are combined with standard NMR spectroscopy to reveal the effects of optical forces on the nuclear hyperpolatization of both absorbing and non-absorbing samples. These experiments provide evidence of a non-resonant coupling between the orbital angular momentum of light and nuclear spins.

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21

Alalawi, Huda. "INVESTIGATION OF NUCLEAR COMPRESSION IN THE AMPT MODELOF NUCLEUS-NUCLEUS COLLISIONS." Kent State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=kent1543405727739039.

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22

Buthelezi, E. Z. (Edith Zinhle). "Near-target and other heavy residues in the interaction of ¹²C and ¹⁶O with ¹⁰³Rh." Thesis, Stellenbosch : University of Stellenbosch, 2004. http://hdl.handle.net/10019.1/15939.

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Dissertation (PhD)--University of Stellenbosch, 2004.
175 Leaves printed single pages, preliminary pages i-xiii and 147 numberd pages. Includes bibliography. List of figures, List of tables.
ENGLISH ABSTRACT: This study forms part of a larger investigation which has as a primary objective the development of a comprehensive theoretical description of all the processes which contribute to the continuum in the interaction of 12C and 16O with nuclei. Previous investigations of 12C and 16O induced reactions on targets with mass close to A = 100 have shown that the experimental excitation functions and recoil range distributions of heavy residues can be reproduced satisfactorily by means of a theoretical model which takes relatively few dominant reaction mechanisms into account. These include the complete fusion of the projectile with the target, the incomplete fusion of break-up α-type fragments (i.e. single α particles, 8Be fragments and for the 16O induced reactions also 12C fragments) with the target and single-nucleon transfer at incident energies above about 15 MeV/nucleon. The mean-field interaction is mainly responsible for these interactions. The thermalization of the intermediate excited nuclei produced in this first stage of the reaction is described by an intranuclear interaction cascade, during which pre-equilibrium emission of particles and clusters may occur, followed by evaporation after statistical equilibrium has been attained. The model also included the probability that break-up α particles may escape with a large fraction of their initial energy after only a few interactions with individual target nucleons following their initial incomplete fusion. The theory also predicted an enhanced isobaric yield for residues with mass similar or near to that of the target. The subsequent analysis of the emission spectra of intermediate mass fragments in these reactions, however, indicated that two additional aspects need to be considered as well in order to reproduce the experimental data. The first is that the projectile may lose a substantial amount of energy in an initial-state interaction before breaking up, which can be described as a friction dissipative process. The second is that several other incomplete fusion channels of “non-α-cluster”- type fragments should also be included in a more complete description of these reactions as their contributions are not negligible. The present study has two main objectives. Firstly, to investigate the isobaric yield in the neartarget mass region by measuring production cross sections for 103Pd, 103mRh and 103Ru. Previous studies only provided data for 103Ag, which constitute only a few percent of the A = 103 isobaric yield. The new data constitute more than 80% of the A = 103 isobaric yield, which provide experimental confirmation of the enhanced isobaric yield in the near-target mass region. The second objective is to perform extensive new calculations of the excitation functions and recoil ranges in order to investigate the predictive power of the extended model in a priori calculations for the entire available data set.
AFRIKAANSE OPSOMMING: Hierdie studie maak deel uit van ‘n meer omvattende ondersoek wat as ‘n primêre doelwit die beskrywing van al die bydraende prosesse tot die kontinuum in die interaksie van 12C en 16O met kerne behels. In vorige ondersoeke van 12C en 16O geïnduseerde reaksies op skywe met massa naby A = 100 kon die eksperimentele opwekkrommes van swaar reskerne en reikwydte distribusies van terugslagkerne bevredigend gereproduseer word met behulp van ‘n teoretiese model wat slegs enkele dominante reaksiemeganismes in berekening bring. Hierdie sluit in die volledige versmelting van die projektiel met die skyfkern, die onvolledige versmelting van opbreek α-tipe fragmente (d.w.s. α- deeltjies, 8Be fragmente, en in die geval van 16O geïnduseerde reaksies ook 12C fragmente) met die skyfkern, en enkel-nukleon oordrag by invalsenergië wat hoër is as ongeveer 15 MeV/nukleon. Die gemiddelde-veld interaksie is hoofsaaklik verantwoordelik vir bogenoemde reaksie meganismes. Die oorgang na termiese ewewig van die opgewekte tussenkerne wat in hierdie eerste stadium van die reaksie gevorm word, word beskryf deur ‘n intrakern interaksie kaskade wat gekenmerk word deur die voorewewigs emissie van deeltjies en klonte van deeltjies, gevolg deur verdamping nadat statistiese ewewig bereik is. Dié model sluit ook die waarskynlikheid in dat opbreek α-deeltjies kan ontsnap met ‘n betekenisvolle fraksie van hul aanvanklike energie na slegs enkele interaksies met individuele skyfnukleone nadat hulle aanvanklik onvolledig versmelt het. In latere studies van die emissiespektra van intermediêre massa fragmente in hierdie reaksies het dit egter geblyk dat twee addisionele aspekte ook in berekening geneem moet word om die eksperimentele data te reproduseer. Eerstens kan die projektiel ‘n substansiële hoeveelheid energie verloor in ‘n aanvangstoestand interaksie voordat dit opbreek, wat beskryf kan word as ‘n wrywingdissipatiewe proses. Tweedens kan verskeie ander onvolledige versmeltingskanale van fragmente met ‘n nié-α-karakter ook betekenisvol bydra en kan hulle dus nie verwaarloos word in ‘n meer volledige beskrywing van hierdie reaksies nie. Die huidige studie het twee hoofdoelwitte. Eerstens word die isobariese opbrengs in die nabyskyfgebied ondersoek deur die produksie kansvlakke van 103Pd, 103mRh en 103Ru te meet. In vorige studies is slegs data verkry vir 103Ag, wat net ‘n klein persentasie van die A = 103 isobariese opbrengs verteenwoordig. Die nuwe data verteenwoordig meer as 80% van die A = 103 isobariese opbrengs, wat eksperimetele bevestiging verleen dat ‘n verhoging in die isobariese opbrengs in die nabyskyfgebied bestaan. Die tweede doelwit is om ‘n volledige stel nuwe a priori berekeninge te doen vir al die opwekkrommes van reskerne en reikwydte distribusies van terugslagkerne wat tans beskikbaar is om sodoende die voorspellings van die nuwe uitgebreide teoretiese model te toets.

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23

Wesolowski, Sarah. "Bayesian Methods for Effective Field Theories." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1500037172071861.

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24

Sadeghi, Mohammad Mehdi 1959. "SYMBOLIC MANIPULATION IN REACTOR PHYSICS." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/275520.

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25

Eriksson, Marcus. "Accelerator-driven systems : Safety and kinetics." Doctoral thesis, Stockholm : Department of Nuclear and reactor Physics, Royal Institute of Technology, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-146.

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26

Qureshi, Babar Ahmed. "Symmetries in noncommutative physics." Related electronic resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2008. http://wwwlib.umi.com/cr/syr/main.

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27

Horsfield, Mark Andrew. "Nuclear Magnetic Resonance in petroleum engineering." Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334172.

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28

Dagdeviren, Nuri Ruhi. "A quark model for nuclear matter." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/32565.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 1985.
MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.
Vita.
Includes bibliographical references.
by Nuri Ruhi Dagdeviren.
Ph.D.

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29

Brooks, Francis Dey. "Physics and applications of scintillation detectors." Thesis, Rhodes University, 1996. http://hdl.handle.net/10962/d1005268.

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The papers submitted in this volume present contributions and reviews on the physics of the scintillation process together with contributions to the development of scintillation detection techniques and the use of these techniques in nuclear physics research and in the applications of nuclear methods to other fields.

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30

Shirinda, Obed. "Signature splitting and inversion in the 186-194 Au Nuclei predicted by the total routhian surface (TRS) and cranked shell model (CSM) calculations." Thesis, University of the Western Cape, 2007. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_6814_1255091175.

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The nearly oblate deformed Au nuclei show rotational bands built on multi quasiparticle excitations [Bou89, Bou92, Gue03, Gue01, Ven92]. Several of these bands are built on rotationally aligned high-j proton and neutron excitations. In many cases bands consisting of two or three signature partner E2 sequences are observed. For some fo these bands signature inversion is found and this feature gives a great challenge to the theoretical models. In this study the researcher performed TRS and CSM calculations for all high-j rotational bands in the p186-194s Au nuclei aiming to predict the signature splitting and inversion phemomena, alignments, gains in alignments, gains in alignment and band crossing frequencies observed.

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31

Allegro, Paula Rangel Pestana. "Estrutura nuclear do 64Cu." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-26112008-105333/.

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Este trabalho tem como principal interesse o estudo das propriedades do núcleo ímpar-ímpar 64Cu utilizando técnicas de espectroscopia de raios em linha. Para o estudo deste núcleo, foi realizada no acelerador Pelletron (Modelo 8-UD, tipo TANDEM) da Universidade de São Paulo a reação de fusão-evaporação 51V(16O, 2pn)64Cu com energia de feixe incidente igual a 70 MeV, utilizando-se um alvo de 4,4 mg/cm2 de 51V com um backing de 7,0 mg/cm2 de Au. As medidas de coincidência das partículas carregadas evaporadas e da radiação gama foram feitas utilizando-se o espectrômetro de raios SACI-PERERE, composto por quatro detectores de GeHP com supressores Compton e 11 detectores E-E de partículas carregadas. Dez novas transições pertencentes ao núcleo 64Cu e um novo estado excitado foram identificados, porém somente uma transição foi posicionada no esquema de níveis conhecido do 64Cu devido principalmente à baixa estatística. Utilizando-se a técnica DCO (Correlações angulares de radiação emitida por estados orientados), determinou-se a multiporaridade de algumas transições pertencentes ao núcleo 64Cu. A descrição do núcleo 64Cu foi feita através do Modelo de Camada em Larga Escala. Para previsões deste modelo, utilizou-se o código Antoine e as interações residuais GXPF1 e fpg, desenvolvidas para as camadas pf e pfg, respectivamente. Os resultados obtidos com este modelo mostram que os estados excitados do núcleo 64Cu podem ser descritos como excitações do tipo partícula-buraco e são caracterizados por funções de onda com alto grau de mistura de configurações.
The main goal of this work is a study of the odd-odd nucleus 64Cu using in-beam gamma-ray spectroscopy. For this study, the fusion-evaporation reaction 51V(16O, 2pn)64Cu at 70 MeV bombarding energy has been performed with the 8-UD Pelletron TANDEM accelerator of the Universidade de São Paulo. The target consisted of a 4.4 mg/cm2 foil of 51V with a 7.0 mg/cm2 Au backing. Gamma-ray and evaporated charged particle coincidences were measured with the SACI-PERERE -ray spectrometer, composed of 4 Comptonsuppressed GeHP and an ancillary system of 11 E-E plastic phoswich scintillators. Ten new -rays and a new excited state have been assigned to 64Cu. Due to low statistics, only one transition could be placed in the known level scheme of 64Cu. The gammaray multipolarities were determined using the Directional Correlations of -rays from Oriented States of Nuclei (DCO) technique. The results were compared with Shell Model calculations using the Antoine code with the GXPF1 and fpg effective interactions, developed for use in the pf shell and pfg shell, respectively. The results obtained with this model have shown that the 64Cu excited states could be described by particle-hole excitations and these states are characterized by wave functions with configuration mixing.

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32

Norman, Ryan Bradley. "Resonance production and nuclear fragmentation for space radiation." Worcester, Mass. : Worcester Polytechnic Institute, 2008. http://www.wpi.edu/Pubs/ETD/Available/etd-042208-131402/.

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Dissertation (Ph.D.)--Worcester Polytechnic Institute.
Keywords: nuclear physics, particle physics, phyiscs, resonance, nuyclear fragmentation, nucleon-nucleon interactions, radiation shileding, heavy-ion physics, space radiation. Includes bibliographical references (leaves 163-141).

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33

Oginni, Babatunde M. "Study Of Nuclear Level Densities From Evaporation Of Compound Nuclei Of Mass Numbers 61, 64, 65, And 82." Ohio University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1241791753.

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34

Podgorsak, Matthew B. "Fricke radiation dosimetry using nuclear magnetic resonance." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59290.

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The spin-lattice relaxation rate R$ sb1$ of irradiated Fricke solution was studied as a function of the absorbed dose D. The R$ sb1$ increases linearly with D up to a dose of $ sim$250 Gy after which the response saturates. A model describing the R$ sb1$ of a solution of either ferrous (Fe$ sp{2+})$ or ferric (Fe$ sp{3+})$ ions is presented; it is based on fast exchange between protons on water molecules in the bulk and protons on water molecules in the coordination shell of the ions. All inherent relaxation parameters of the different proton groups are determined. An extension of the model is made to describe the spin-lattice relaxation behaviour of irradiated Fricke solution. Good agreement between model predictions and experimental results is observed. The model relates the spin-lattice relaxation rate of a Fricke dosimeter to the chemical yield of ferric ion, thus creating an absolute dosimetry technique. Various practical aspects of the NMR-Fricke system are described.

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35

Eskin, Joshua Daniel 1960. "Semiconductor gamma-ray detectors for nuclear medicine." Diss., The University of Arizona, 1997. http://hdl.handle.net/10150/288740.

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Semiconductor-based gamma-ray-imaging detectors are under development for use in high-resolution nuclear medicine imaging applications. These detectors, based on cadmium zinc telluride, hold great promise for delivering improved spatial resolution and detection efficiency over current methods. This dissertation presents work done on three fronts, all directed toward enhancing the practicality of these imaging devices. Electronic readout systems were built to produce gamma-ray images from the raw signals generated by the imagers. Mathematical models were developed to describe the detection process in detail. Finally, a method was developed for recovering the energy spectrum of the original source by using maximum-likelihood estimation techniques. Two electronics systems were built to read out signals from the imaging detectors. The first system takes signals from a 48 x 48-pixel array at 500 k samples per second. Pulse-height histograms are formed for each pixel in the detector, all in real time. A second system was built to read out four 64 x 64 arrays at 4 million pixels per second. This system is based on digital signal processors and flexible software, making it easily adaptable to new imaging tasks. A mathematical model of the detection process was developed as a tool for evaluating possible detector designs. One part of the model describes how the mobile charge carriers, which are released when a gamma ray is absorbed in a photoelectric interaction, induce signals in a readout circuit. Induced signals follow a "near-field effect," wherein only carriers moving close to a pixel electrode produce significant signal. Detector pixels having lateral dimensions that are small compared to the detector thickness will develop a signal primarily due to a single carrier type. This effect is confirmed experimentally in time-resolved measurements and with pulse-height spectra. The second part of the model is a simulation of scattering processes that take place when a gamma ray is absorbed within the detector volume. A separate simulation predicts the spreading of charge carriers due to diffusion and electrostatic forces. The models are used in a technique to improve the energy resolution of the detectors by estimation of the source spectrum using the Expectation-Maximization algorithm.

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36

Stewart, Chris. "Strings, quarkonium and nuclear physics in lattice QCD." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ56269.pdf.

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37

Schmitt, Harry Adam. "Orthosymplectic supersymmetry and its application to nuclear physics." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184522.

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Phenomenological models have long been employed by nuclear physicists to explain systematic trends in data. The Geometrical Model of Bohr, Mottelson and Rainwater (GM) and the Interacting Boson Model (IBM) are two such models that have been used to study the spectra of even-even nuclei. The IBM differs from previous boson models in that the total number of bosons is conserved and finite. In the GM the bosons of lowest angular momentum have ℓ = 2 and are taken to represent quadrupole shape vibrations, whereas in the IBM the bosons are generally taken to have ℓ = 0, 2 and can be interpreted as correlated pairs of fermions. These models have been extended to handle the neighboring odd-even nuclei by considering the interaction of a fermion with the bosonic space. If the fermionic space consists of the single-particle angular momenta j₁, j₂, ..., then the largest group describing this mixed system of bosons and fermions is the product group Uᴮ(5) x Uᶠ(m(j)) (GM) or Uᴮ(6) x Uᶠ(m(j)) (IBM), where m(j) = Σ(2jᵢ + 1). If one of the subgroups of Uᴮ(5) or Uᴮ(6) is isomorphic to one of the subgroups of Uᶠ(m(j)), then we can combine the two group chains into a common bose-fermi group chain. These combined bose-fermi groups have been used extensively in the Interacting Boson-Fermion Model (IBFM) to study odd-even nuclei and have been claimed as evidence for the existence of supersymmetries; however, the superalgebras associated with these supersymmetries were never identified. We have identified, for the first time, the superalgebras that are associated with some of these combined bose-fermi symmetries. This superalgebra, the non-compact orthosymplectic superalgebra Osp(4s+2/2,R), is fundamentally different than those previously used in the IBFM, where the product algebra was simply embedded into the superalgebra U(6/m(j)). The U(6/m(j)) superalgebras do not imply any particular coupling scheme, and hence cannot be associated with any particular one of the combined bose-fermi algebras. The last few chapters are devoted to a study of coherent states for the non-compact orthosymplectic supergroups Osp(1/2N,R) and Osp(2/2N,R), although the results generalize rather easily to the compact versions of these supergroups. These coherent states, besides being of mathematical interest, form the basis for a study of Osp(M/2N,R) coherent states. (Abstract shortened with permission of author.)

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38

Curtis, Deborah Claire. "Advancements in nuclear waste assay." Thesis, University of Birmingham, 2008. http://etheses.bham.ac.uk//id/eprint/153/.

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The research described in this thesis is directed at advancing the state of the practice of the non-destructive gamma-ray assay of nuclear waste containers. A number of potentially accuracy-limiting issues were identified and addressed, resulting in new developments which were implemented on an instrument prior to entering it into service. A set of Pu reference sources used for experimental data have been studied to determine the internal composition (density and fill height) of the sources to assist with validation of a point kernel model. This model has been used to observe the behaviour of gamma-rays in lumps of fissile material from plutonium over the mass range 0.001g to 350g, for a number of densities corresponding to Pu, PuO$_2$ and PuF$_3$. Established lump corrections have been analysed and have been found to produce large over- and under-corrected results for the range of masses. Due to the inadequacies of current techniques, a new Pu self-absorption correction method has been developed using the data from numerical simulations, allowing nature to reveal the correlations rather than traditional approaches based upon approximate models. For a 25g 1cm-high Pu flat-plate of density 15g.cm$^{-3}$, the developed Pu correction produces a result of (24.9 ± 8.8)g compared to (19.5 ± 0.9)g for the Fleissner 2-line method, and (14.7 ± 0.4)g for the Infinite Energy Extrapolation method. The developed Pu correction method has been extended to the application of uranium lumps in waste matrices, provided the enrichment of the sample is known or may be determined via sophisticated isotopic analysis methods such as MGAU or FRAM. The U self-absorption correction method has been found to produce results within 30% of the true mass of the sample for the lumps studied. An analysis of ‘real drum’ effects has been performed, including the revisiting of the Total Measurement Uncertainty (incorporating the uncertainty components of the new Pu and U self-absorption corrections) and results from known sources placed in artificial inhomogeneous waste matrices assayed inside a Canberra Auto Q2 system.

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39

Okamura, Kazuya. "Algebraic and Statistical Approach to Infinite Quantum Systems." 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/188458.

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40

Tokiyasu(Okamura), Atsushi. "Search for the K-pp bound state using the d(γ,K+π-)X reaction at Eγ=1.5-2.4 GeV". 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/188483.

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41

Xu, Ping. "New methods in nuclear magnetic resonance spectroscopy." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239177.

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42

Vachaspati, Pranjal. "Optimizing tensor contractions for nuclear correlation functions." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/92687.

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Анотація:

Thesis: S.B., Massachusetts Institute of Technology, Department of Physics, 2014.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 37-38).
Nuclear correlation functions reveal interesting physical properties of atomic nuclei, including ground state energies and scattering potentials. However, calculating their values is computationally intensive due to the fact that the number of terms from quantum chromodynamics in a nuclear wave function scales exponentially with atomic number. In this thesis, we demonstrate two methods for speeding up this computation. First, we represent a correlation function as a sum of the determinants of many small matrices, and exploit similarities between the matrices to speed up the calculations of the determinants. We also investigate representing a correlation function as a sum of functions of bipartite graphs, and use isomorph-free exhaustive generation techniques to find a minimal set of graphs that represents the computation.
by Pranjal Vachaspati.
S.B.

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43

Tirfessa, Negussie. "Effective field theory approach to nuclear matter /." The Ohio State University, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486401895208651.

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44

Subedi, Ramesh Raj. "Studying Short-Range Correlations with the ¹²C(e,e'pn) Reaction." [Kent, Ohio] : Kent State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=kent1194961371.

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45

Mudau, Lufuno Julia. "Emission of ³He ⁴He and ⁶He particles produce from the interaction of ¹²C with ⁹³Nb at 400 MeV incident energy." Thesis, University of the Western Cape, 2005. http://hdl.handle.net/11394/1903.

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Magister Scientiae - MSc
The inclusive double di®erential cross sections of 3He, 4He, and 6He par- ticles produced from the interaction of 12C with 93Nb at 400 MeV incident energy were extracted from the prescaled singles spectra which were mea- sured in conjunction with the correlation between 8Be fragments and ® par- ticles. A further aim of this project was to test the detector e±ciencies and energy calibrations by comparing the alpha and 8Be prescaled singles data with existing inclusive cross sections of the same reaction. The absolute cross sections of 3He and 6He fragments have been extracted based on the absolute normalization of the alpha particle spectra. A study of the inclusive spectra of 3He and 6He suggest similar features to those seen in the alpha particle spectra. These features are described by the projectile break-up and nucleon coalescence mechanisms. A theoretical model which takes both these mech- anisms into account was applied to describe 3He and 6He fragments. The model is able to reproduce reasonably well the inclusive energy spectra of the 3He and 6He fragments. These results are found to be consistent with previous studies of the emission of intermediate mass fragments.
South Africa

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46

Shorto, Julian Marco Barbosa. "Mecanismos de Reação nos Sistemas 16,18O + 63,65Cu." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-02102007-121454/.

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Анотація:

Foram medidas as funções de excitação quase-elásticas para os sistemas 16,18O + 63,65Cu, no ângulo de 161ºe em energias compreendidas entre 30 e 48MeV, no referencial do laboratório. O termo quase-elástico aqui significa a soma do espalhamento elástico, dos espalhamentos inelásticos e das reações de transferência. Todos os cuidados foram tomados para se obter dados de alta precisão em pequenos passos de 0,5MeV de energia, pois o objetivo primeiro deste trabalho era realizar operações matemáticas (derivadas) sobre os pontos experimentais a fim de deduzir as distribuições de barreiras quase-elásticas desses sistemas. O ângulo de detecção escolhido, o maior possível com o arranjo experimental utilizado, objetivava estudar diretamente a competição entre a fusão e os processos diretos quando ambos os processos são alimentados pelas mesmas ondas parciais. Nessa situação, as representações das distribuições de barreiras de fusão e quase-elástica devem ser equivalentes devido à conservação do fluxo. O intervalo de energia foi escolhido para cobrir a região em torno da barreira coulombiana onde as distribuições de barreiras constituem um bom instrumento para o estudo dos mecanismos de reação. Além das medidas quase-elásticas inclusivas, a resolução em carga do detector permitiu que as funções de excitação de alguns canais de transferência fossem também medidas no mesmo ângulo e energias citados acima. A análise teórica dos dados foi realizada no âmbito do modelo de Canais de Reações Acoplados através do programa FRESCO. Outro objetivo deste trabalho foi a utilização de núcleos ímpares como alvos, pois os seus spins não nulos introduzem fenômenos adicionais ao mecanismo de reação que, eventualmente, podem se detectados pelas distribuições de barreiras. Um novo procedimento de cálculo foi empregado pela eliminação de qualquer potencial imaginário na região de interação, substituindo-o pela inclusão do maior número possíveis de canais de reação no cálculo de canais acoplados. Dessa maneira, elimina-se um problema muito comum nos cálculos de canais acoplados, que é o de misturar canais de reação com potencial imaginário deduzido a partir do ajuste de espalhamento elástico, o qual já contém o efeito desses canais. Além disso, e esse é um ponto importante desta análise, foi utilizada a parte real do Potencial de São Paulo, um potencial de dupla-convolução sem parâmetros livres, para simular a interação nuclear entre projéteis e alvos. Uma vez que todos os parâmetros nucleares necessários aos cálculos de canais acoplados advieram da literatura, nossa análise apresenta previsões teóricas que devem ser comparadas com os dados experimentais, o que é muito diferente dos ajustes aos dados através da variação de vários parâmetros livres. Outra característica importante da análise teórica empreendida neste trabalho é a utilização de todos os dados disponíveis na literatura para esses sistemas nas energias em torno da barreira. Assim, as previsões teóricas puderam ser comparadas com um grande conjunto de dados e ganharam grande consistência e amplitude. Os resultados obtidos com essas análises revelaram uma forte coletividade dos núcleos 63Cu e 65Cu, sendo que os três primeiros estados vibracionais quadrupolares 1/2-, 5/2- e 7/2- predominam sobre os demais estados excitados. As reações de transferência têm pequeno efeito sobre os demais processos, mas sofrem forte influência deles.Uma exceção é a transferência de dois nêutrons do 18O para o 63Cu, cuja importância nesse sistema é considerável. Além disso, foi constatado que, mesmo nesses sistemas de peso médio, o mecanismo de reorientação do spin do estado fundamental, de ambos os alvos, tem grande efeito em todos os processos nucleares analisados, mas é particularm ente forte no espalhamento elástico em ângulos traseiros. Finalmente, as distribuições de barreiras quase-elásticas se mostraram sensíveis a todos esses mecanismos de reação e constituem, de fato, uma excelente ferramenta para o estudo de reações nucleares.
The quasi-elastic excitation functions for the systems 16,18O + 63,65Cu have been measured, at the angle 161º and at energies between 30 and 48MeV, in the laboratory reference system. The quasi-elastic term refers to the sum of the elastic scattering, the inelastic scattering and the transfer reactions. Care has been taken in order to obtain high precision data in small energy steps of 0,5MeV, because the aim of this work was to perform mathematics operations (derivates)on the experimental points, to deduce the quasi-elastic barrier distributions of these systems. The choice of this angle of detection, the largest possible, allows the direct study of the competition between the fusion and the direct processes, as both are fed by the same partial waves. The energy interval has been chosen to cover the region around the Coulomb barrier, where the barrier distributions constitute a good instrument for the study of the reaction mechanisms at these energies. Beyond the inclusive quasi-elastic, measurements of some transfer channels, at the same angle and energies mentioned above, were possible due to the charge resolution of the detector. The theoretical analysis of the data has been done on the scope of the coupled reaction channel model, with the code FRESCO. Another aim of this work was the utilization of odd-mass nuclei as targets, as their non-vanishing spins introduce additional phenomena to the reaction mechanisms, that might, eventually, be detected by the barrier distributions. A new calculation procedure has been used by the elimination of any imaginary potential at the interaction region, and it\'s substitution by the inclusion of the largest number as possible of channels at the coupled reaction channel calculation. Another important feature of the theoretical analysis is the utilization of many data available in the literature for these systems at energies around the barrier. Thus, the theoretical forecast could be compared with a great set of data and earned consistency and amplitude. The results obtained with this analysis revealed a strong collective behaviour of the 63Cu and 65Cu nuclei, and the first three quadrupolar vibrational states 1/2-, 5/2- and 7/2- prevail over the other excited states. The transfer reactions have small effect over the others processes, but are greatly influenced by them. There is an exception, the two neutron transfer from 18O to 63Cu, whose importance on this system is considerable. Besides, it was revealed that even on these medium weight systems, the ground state reorientation mechanism, of both targets, have large effect on all the analysed nuclear processes, but is strongest on the elastic scattering at back angles. Finally, the quasi-elastic barriers distributions showed up to be sensible to all of these reaction mechanisms and constitute an excellent tool for the study of nuclear reactions.

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47

Alshammri, Albandry. "QUALITY ASSURANCE (QA) ANALYSIS IN √(s_NN )=54 GEV AU+AU COLLISIONS." Kent State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=kent154332321560662.

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48

Nasri, Salah Schechter Joseph. "Neutrinos in particle physics and cosmology." Related Electronic Resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2003. http://wwwlib.umi.com/cr/syr/main.

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49

Windham, Gordon. "Spin dependence in heavy ion induced nuclear reactions." Thesis, University of Surrey, 1986. http://epubs.surrey.ac.uk/843452/.

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Анотація:

The interest of this work is to explore the spin dependent effects of projectile structure in nuclear heavy ion induced reactions. The projectiles are considered to consist of two clusters which remain inert, the intercluster wavefunctions are obtained by the use of the orthogonality condition model. Excitation to the low lying projectile states is included by the use of coupled channels calculations. The projectile excited states are included by allowing excitation in the inter cluster wavefunctions. Coupling to the excited states is performed by multipole terms arising from a single folding model, which is used consistently throughout the work. The effects of projectile excitation are considered in two areas, elastic and inelastic scattering, and transfer reactions. It is found that the inclusion of the projectile excited states has a very strong effect on the spin dependent elastic observables, in particular the vector analysing powers. In contrast to earlier analysis it is found that projectile excitation plays a dominant role in reproducing the experimentally observed vector analysing powers for the elastic scattering of 6Li from 16O and 28Si at 22.8 MeV. Projectile excitation is also seen to produce strong spin dependent effects in the elastic scattering of Li from 120Sn at 44 MeV and of 19Ffrom 28Si at 60 MeV. The inclusion of projectile excitation via CCBA calculations produces changes in the transfer cross section for the 28Si (19F, 16O)31P(1/2+ ,g.s.) reaction. The observed changes can be understood in terms of the effects of spin dependence in the reaction path. The inclusion of projectile excitation however does not significantly improve the quality of the agreement with experimental data.

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50

Duce, Suzanne Louise. "Nuclear magnetic resonance imaging and spectroscopy of food." Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240194.

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