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Pages
 Title
 The ¹⁵°Sm(t, ³He)¹⁵°Pm* and ¹⁵°Nd(³He, t)¹⁵°Pm* reactions and applications for 2v and 0v double beta decay
 Creator
 Guess, Carol Jeanne
 Date
 2010
 Collection
 Electronic Theses & Dissertations
 Title
 Charged particle correlations from intermediate energy nuclear reactions
 Creator
 Cebra, Daniel Alan
 Date
 1990
 Collection
 Electronic Theses & Dissertations
 Title
 A study of the mechanism of ¹⁶0induced reactions between 140 and 315 MeV incident energies
 Creator
 Awes, Terry Clayton
 Date
 1981
 Collection
 Electronic Theses & Dissertations
 Title
 A survey of the (³He, ⁷Be) reaction at 70 MeV
 Creator
 Steele, William Frederick, 1947
 Date
 1974
 Collection
 Electronic Theses & Dissertations
 Title
 Charm muoproduction in deep inelastic scattering at 269 GeV/c
 Creator
 Kiley, James Philip
 Date
 1981
 Collection
 Electronic Theses & Dissertations
 Title
 ¹⁴N(p, p') at 29.8, 36.6, and 40.0 MeV and the strength of the tensor force in nuclear reaction
 Creator
 Fox, Stanley Haim, 1942
 Date
 1972
 Collection
 Electronic Theses & Dissertations
 Title
 Transport phenomena in heavyion reactions
 Creator
 Shi, Lijun
 Date
 2003
 Collection
 Electronic Theses & Dissertations
 Title
 Determination of the Coulomb correction and isovector terms of the nucleonnucleus optical model potential from neutron elastic scattering at 30.3 and 40 MeV
 Creator
 DeVito, Raymond Peter
 Date
 1979
 Collection
 Electronic Theses & Dissertations
 Title
 Physics of singletop quark production at hadron colliders
 Creator
 Carlson, Doulgas Olaf
 Date
 1995
 Collection
 Electronic Theses & Dissertations
 Title
 Nuclear reactions in the crust of accreting neutron stars
 Creator
 Lau, Kit Yu
 Date
 2012
 Collection
 Electronic Theses & Dissertations
 Description

There have been many discoveries from observations of accreting neutron stars in Xray binaries. Many of the observed phenomena such as superbursts or the cooling of quasipersistent transients during their quiescent state are affected by the thermal properties and the composition of the crust. To model the nuclear energy release and crust composition, we build up a first complete network with pycnonuclear fusion. We run a consistent nuclear reaction network that follows the evolution of an...
Show moreThere have been many discoveries from observations of accreting neutron stars in Xray binaries. Many of the observed phenomena such as superbursts or the cooling of quasipersistent transients during their quiescent state are affected by the thermal properties and the composition of the crust. To model the nuclear energy release and crust composition, we build up a first complete network with pycnonuclear fusion. We run a consistent nuclear reaction network that follows the evolution of an accreted fluid element from the atmosphere down to the inner crust. We take into account a majority of the most important nuclear processes including electron capture, neutron capture, neutron emissions, $beta decay, and pycnonuclear fusion reactions. The result of the model shows that there is nuclear reaction path splitting in the crust of accreting neutron stars due to the usage of finite electron capture rates. The pycnonuclear fusion reactions can occur at a shallower depth than previously thought. The composition deep inside the inner crust is mainly 40Mg, independent of the initial composition of the ashes of the outer crust. The inner crust is found to be very pure no matter what the initial abundance of the ashes is in the outer crust. The neutron drip locates at a higher density in our model. In general, the nuclear reaction path and the heat energy generation in the inner crust are significantly different from the previous work.
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 Title
 ²⁰Mg beta decay and the ¹⁵O(alpha, gamma)¹⁹Ne(p, gamma)²⁰Na reaction sequence in Type I xray bursts
 Creator
 Glassman, Brent
 Date
 2020
 Collection
 Electronic Theses & Dissertations
 Description

Constraining the ¹⁵O(alpha, gamma)¹⁹Ne(p, gamma)²⁰Na reaction rate is critically important for accurately simulating xray burst light curves, our only xray burst observable from Earth. Both the ¹⁵O(alpha, gamma)¹⁹Ne(p, gamma) and )¹⁹Ne(p, gamma)²⁰Na reaction rates have been studied using a multitude of experimental techniques, yet only upper limits had been determined at the outset of the present work. The ¹⁵O(alpha, gamma)¹⁹Ne(p, gamma) reaction in particular has been singled out as the...
Show moreConstraining the ¹⁵O(alpha, gamma)¹⁹Ne(p, gamma)²⁰Na reaction rate is critically important for accurately simulating xray burst light curves, our only xray burst observable from Earth. Both the ¹⁵O(alpha, gamma)¹⁹Ne(p, gamma) and )¹⁹Ne(p, gamma)²⁰Na reaction rates have been studied using a multitude of experimental techniques, yet only upper limits had been determined at the outset of the present work. The ¹⁵O(alpha, gamma)¹⁹Ne(p, gamma) reaction in particular has been singled out as the most important reaction rate of all currently unknown rates to measure. Utilizing the beta decay of ²⁰Mg to populate ²⁰Na excited states, we further constrain the ¹⁹Ne(p,gamma)²⁰Na reaction rate by searching for gamma decays from the most important resonance at E_x=2647 keV. Additionally, by populating ²⁰Na excited states high above the proton threshold, we populate the most important ¹⁹Ne resonance for measuring the ¹⁵O(alpha, gamma)¹⁹Ne(p, gamma) reaction rate at E_x=4.03 MeV. Herein, the results of this study are reported including: The full ²⁰Mg betadelayed gamma ray spectrum and decay scheme; the upper limit on the beta decay feeding of the ²⁰Na 2647 keV state; the Doppler broadening analysis of nine gamma ray peaks from six excited states in ¹⁹Ne; the intensity of ²⁰Mg(beta,p,gamma) to the 4.03 MeV state in ¹⁹Ne; the measurement of the ²⁰Na excitation energy at 7.44 {+0.25_{0.22 MeV feeding the 4.03 MeV state in ¹⁹Ne; and the measurement of the center of mass proton energy for the feeding of the important 4.03 MeV state in ¹⁹Ne at 1.23 {+0.25_{0.22 MeV.
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 Title
 Interplay of anisotropy of momentum distributions and mean fields in heavyion collisions
 Creator
 Simon, Christian Helmut
 Date
 2011
 Collection
 Electronic Theses & Dissertations
 Description

We construct an explicitly anisotropic nucleonic mean field, for a phasespace density anisotropic in momentum, convenient for modeling of nuclear reactions, using separable interactions in momentum space. We demonstrate the flexibility of our separable model for the potential energy density
V associated with the momentumdependent mean fieldU , by approximating the respective expressions by Welkeet al. which also serve as reference....
Show moreWe construct an explicitly anisotropic nucleonic mean field, for a phasespace density anisotropic in momentum, convenient for modeling of nuclear reactions, using separable interactions in momentum space. We demonstrate the flexibility of our separable model for the potential energy densityV associated with the momentumdependent mean fieldU , by approximating the respective expressions by Welkeet al. which also serve as reference. Therefore, we apply an expansion in spherical harmonics, comprising scalar and tensorial terms to Welke's potential energy density, laying open the anisotropy of the mean field. Groundstate properties in the reference model can be well described within our framework. The anisotropy in our model is parameterized by relying on anisotropic Gaussian distributions for excitedmatter scenarios. We show that the strongly anisotropic mean field of 2 Fermi spheres in momentum space can be reproduced within our framework. As for the contribution to the velocity field deduced from our mean field parameterization, we find that for large anisotropies particle velocities tend to be weakly directed along the transverse momentum axis. Our parameterization can be applied in BUU transport simulations with gain over an approach of the type of Welkeet al. in reduced computational cost and reduced errorproneness.
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 Title
 Effects of nonlocality on transfer reactions
 Creator
 Titus, Luke
 Date
 2016
 Collection
 Electronic Theses & Dissertations
 Description

Nuclear reactions play a key role in the study of nuclei away from stability. Singlenucleon transfer reactions involving deuterons provide an exceptional tool to study the singleparticle structure of nuclei. Theoretically, these reactions are attractive as they can be cast into a threebody problem composed of a neutron, proton, and the target nucleus.Optical potentials are a common ingredient in reactions studies. Traditionally, nucleonnucleus optical potentials are made local for...
Show moreNuclear reactions play a key role in the study of nuclei away from stability. Singlenucleon transfer reactions involving deuterons provide an exceptional tool to study the singleparticle structure of nuclei. Theoretically, these reactions are attractive as they can be cast into a threebody problem composed of a neutron, proton, and the target nucleus.Optical potentials are a common ingredient in reactions studies. Traditionally, nucleonnucleus optical potentials are made local for convenience. The effects of nonlocal potentials have historically been included approximately by applying a correction factor to the solution of the corresponding equation for the local equivalent interaction. This is usually referred to as the Perey correction factor. In this thesis, we have systematically investigated the effects of nonlocality on $(p,d)$ and $(d,p)$ transfer reactions, and the validity of the Perey correction factor. We implemented a method to solve the single channel nonlocal equation for both bound and scattering states. We also developed an improved formalism for nonlocal interactions that includes deuteron breakup in transfer reactions. This new formalism, the nonlocal adiabatic distorted wave approximation, was used to study the effects of including nonlocality consistently in $(d,p)$ transfer reactions. For the $(p,d)$ transfer reactions, we solved the nonlocal scattering and bound state equations using the PereyBuck type interaction, and compared to local equivalent calculations. Using the distorted wave Born approximation we construct the Tmatrix for $(p,d)$ transfer on $^{17}$O, $^{41}$Ca, $^{49}$Ca, $^{127}$Sn, $^{133}$Sn, and $^{209}$Pb at $20$ and $50$ MeV. Additionally we studied $(p,d)$ reactions on $^{40}$Ca using the the nonlocal dispersive optical model. We have also included nonlocality consistently into the adiabatic distorted wave approximation and have investigated the effects of nonlocality on on $(d,p)$ transfer reactions for deuterons impinged on $^{16}$O, $^{40}$Ca, $^{48}$Ca, $^{126}$Sn, $^{132}$Sn, $^{208}$Pb at $10$, $20$, and $50$ MeV. We found that for bound states the Perry corrected wave functions resulting from the local equation agreed well with that from the nonlocal equation in the interior region, but discrepancies were found in the surface and peripheral regions. Overall, the Perey correction factor was adequate for scattering states, with the exception for a few partial waves. Nonlocality in the proton scattering state reduced the amplitude of the wave function in the nuclear interior. The same was seen for nonlocality in the deuteron scattering state, but the wave function was also shifted outward. In distorted wave Born approximation studies of $(p,d)$ reactions using the PereyBuck potential, we found that transfer distributions at the first peak differed by $1535\%$ as compared to the distribution resulting from local potentials. When using the dispersive optical model, this discrepancies grew to $\approx 3050\%$. When nonlocality was included consistently within the adiabatic distorted wave approximation, the disagreement was found to be $\sim 40\%$. If only local optical potentials are used in the analysis of experimental $(p,d)$ or $(d,p)$ transfer cross sections, the extracted spectroscopic factors may be incorrect by up to $50\%$ in some cases due to the local approximation. This highlights the necessity to pursue reaction formalisms that include nonlocality exactly.
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 Title
 A Study of the Gamow Teller Strength in 40,42,44, 48 Ca from the (p, n) Reaction at 119 MeV
 Creator
 Narayanaswamy, Janaki
 Date
 1983
 Collection
 Electronic Theses & Dissertations
 Title
 Coulomb displacement energies of lf/₂ shell mirror nuclei
 Creator
 Mueller, Dennis Warren, 1946
 Date
 1976
 Collection
 Electronic Theses & Dissertations
 Title
 The gfactor of the 19/2⁻ state in ¹¹⁵Sb and high spin structure of ¹⁸⁰W
 Creator
 Faber, Steven Ray
 Date
 1979
 Collection
 Electronic Theses & Dissertations
 Title
 Nuclear reactions in type IA supernovae : effects of progenitor composition and detonation asymmetry
 Creator
 Chamulak, David A.
 Date
 2009
 Collection
 Electronic Theses & Dissertations
 Title
 Anomalous [Epsilon]/[beta] decay branching ratios
 Creator
 Firestone, Richard Brian, 1945
 Date
 1974
 Collection
 Electronic Theses & Dissertations
 Title
 High energy photon production in nuclear reactions
 Creator
 Tam, Chui Ling
 Date
 1989
 Collection
 Electronic Theses & Dissertations
 Title
 A study of ¹⁹², ¹⁹⁴, ¹⁹⁶, ¹⁹⁸pt using the (p, t) and (p, p') reactions and the interacting boson approximation model
 Creator
 Deason, Paul Thomas
 Date
 1979
 Collection
 Electronic Theses & Dissertations