Source: Dissertation Abstracts International, Volume: 40-07, Section: B, page: 3162. / Thesis (Ph.D.)--The Florida State University, 1979.

In heavy-ion induced proton pickup reaction existing theories sometimes describe the data and sometimes they do not. No consistent patterns of failure or success has yet emerged. The present study was undertaken to investigate whether the structure of the projectile-ejectile is important in de / Source: Dissertation Abstracts International, Volume: 41-10, Section: B, page: 3818. / Thesis (Ph.D.)--The Florida State University, 1981.

Heavy ion reactions were used to produce nuclei away from beta stability in the mass region A(TURNEQ)80. The irradiated targets were transported to an isolated detector site using a rapid target transfer (Rabbit) system to aid in the study of weak products produced in these reactions and to protect the Ge(Li) detectors used in the experiments. The "Rabbit" system constructed for this purpose was a pneumatic type and was controlled by a NIM controller. The NIM controller, a unique feature of this system, was constructed with TTL and CMOS circuits and works in conjunction with a leaky integrator and a UNIVAC 6130 computer. The "Rabbit" system was used in lifetime, gamma-gamma coincidence measurements and beta-gamma coincidence measurements. / Lifetime measurements were used to study the decay of ('79)Sr produced in the reaction ('54)Fe + ('28)Si at 90 MeV (lab). The lifetime of the ground state of ('79)Sr was measured and a positron feeding to the 39.3-keV level in ('79)Rb was established. Lifetime measurements were also used to study the decay of ('81m)Rb, which is produced in the reaction ('68)Zn + ('16)O at 56 MeV (lab). A positron feeding from the isomeric level in ('81)Rb to the 49.6-keV level in ('81)Kr was established. In addition, lifetime measurements were used to help identify gamma rays produced in the reactions ('68)Zn + ('16)O and ('70)Ge + ('16)O at 56 MeV (lab). / The reaction ('68)Zn + ('16)O was also studied with the gamma-gamma coincidence technique. Extensive level schemes were constructed and new levels were established for the decays of ('81)Rb and ('81)Sr. The beta-gamma coincidence technique was used in the study of the reaction ('70)Ge + ('16)O to investigate the ground state and isomeric levels of ('83)Y and ('84)Y. The order and relative separation of these levels were tentatively established for ('83)Y. The Q-value and J('(pi)) of the ground state were established and tentative J('(pi)) assignments were made for the isomeric levels in ('84)Y. / The information from these measurements as well as information previously known are then used to look for apparent systematics in a number of isotopes of Zr, Y, Sr, Rb and Kr. Possible explanations of these trends are given in terms of the spherical shell model. / Source: Dissertation Abstracts International, Volume: 42-01, Section: B, page: 0264. / Thesis (Ph.D.)--The Florida State University, 1981.

In order to study high-spin states in beta-stable and neutron-rich nuclei, in-beam gamma-ray spectroscopy was performed following triton-induced reactions on heavy nuclei. Initial studies on isotopically pure targets of ('208)Pb confirm that the dominate reaction for 10-16 MeV tritons is compound nucleus formation, followed by emission of two neutrons. The (t,2n) reaction was found to populate low-spin states as well as high-spin states, and to sufficiently align the high-spin states so that information on transition multipolarities can be obtained from gamma-ray angular distribution measurements. Preliminary experiments on ('232)Th show that for compound nuclei produced by triton bombardment of actinide targets, decay by neutron emission competes favorable with fission, so that conversion electron spectroscopy following (t,xn) reactions may be useful for studying actinide nuclei. / Triton bombardment of isotopically pure ('196)Pt and ('198)Pt targets was used to study ('197)Au and ('199)Au, produced by the (t,2n) reaction. Excitation function, pulsed beam, and gamma-gamma coincidence experiments were performed on both targets, and gamma-ray angular distributions were measured in ('199)Au. Level schemes constructed from this data show that the systematic trends observed in the lighter odd-mass gold nuclei continue in ('197)Au, but deviations in these trends occur in ('199)Au. A 6 (+OR-) 2 ns isomer seen in ('197)Au is believed to be a 2 1/2+, three particle state. The theory which best explains the results of these experiments is the cluster-vibration model, as only this model correctly predicts the large level density of negative-parity states found at excitation energies of 1-2 MeV. / Source: Dissertation Abstracts International, Volume: 43-03, Section: B, page: 0722. / Thesis (Ph.D.)--The Florida State University, 1982.

Two nuclear isomers were studied using in-beam gamma-ray spectroscopic techniques in conjunction with the reactions ('204)Hg(t,2n(gamma))('205)Tl and ('204)Hg(t,p(gamma))('206)Hg. The isomeric state in ('205)Tl was determined to have J('(pi)) = 25/2('+) with the major configuration (('206)Pb7('-) x h(,11/2)('-1)). The mean lifetime and gyromagnetic ratio for the state were determined to be (tau)(,m) = 3.7 (+OR-) 0.3 (mu)sec and g = 0.544 (+OR-) 0.008, respectively. Using this g-factor and previously measured g-factor for the ('206)Pb7('-) state, a g-factor, g = 1.264 (+OR-) 0.027, was deduced for an h(,11/2) proton state. For the nucleus ('206)Hg a new isomeric state was seen at 2.102 MeV excitation energy. This state was determined to have J('(pi)) = 5('-) with a mean lifetime (tau)(,m) = 3.1 (+OR-) 0.3 (mu)sec and the gyromagnetic ratio was measured to be 1.09 (+OR-) 0.01. The major configuration of the isomeric state if {h(,11/2)('-1)s(,1/2)('-1)} and using the value for g(h(,11/2)) determined from ('205)Tl, the g-factor for a 3s(,1/2) proton state was determined. / Source: Dissertation Abstracts International, Volume: 43-04, Section: B, page: 1098. / Thesis (Ph.D.)--The Florida State University, 1982.

The study of exotic nuclei, and their implication for Astrophysics have become a driving force in low-energy nuclear science, nationally recognized by the construction of the Facility for Rare Isotope Beams (FRIB) laboratory. To maximize the potential provided by beams of exotic nuclei, novel detector systems and analysis techniques must be developed, a current focus of the Florida State University (FSU) group. Experimental results from commissioning experiments with the ANASEN and RESONEUT detectors at FSU are presented. The neutron deficient ⁹C nucleus was studied through the ⁸B+p resonant elastic scattering reaction. The experiment was conducted during the commissioning of the ANASEN detector in 2012. Due to cryogenics problems, the experiment was stopped prematurely. Through analysis of the partial data set, it was shown that a full analysis could be performed, on complete data sets, for future proton resonance elastic scattering experiments. Results from the ¹⁹O(d,p)²⁰O experiment, also conducted as a part of the commissioning of the ANASEN detector at FSU, will be presented. It was found that heavy ion recoils from the (d,p) reactions were reaching the active zone of the proportional counter, and subsequently producing UV-light radiation that degraded the proportional counter performance. This discovery lead to a re-design of the proportional counter, which is currently being constructed by the ANASEN group at Louisiana State University. An experimental study of low-lying proton resonances in ²⁰Na was performed using the proton transfer ¹⁹Ne(d,n)²⁰Na(p) reaction as part of the commissioning campaign of experiments with the RESONEUT detector. This reaction is comparable to the direct proton capture, ¹⁹Ne(p,ɣ)²⁰Na, which is of astrophysical significance in the breakout from the Hot CNO-cycle. Using protons detected from the decay of ²⁰Na, three resonances were observed, at energies of 0.44 MeV, 0.66 MeV, and 0.82 MeV above the proton threshold. The resonance strengths were determined, and the subsequent ¹⁹Ne(p,ɣ)²⁰Na stellar reaction rate was calculated. A discussion of this reaction rate in the context of the breakout from the Hot CNO-cycle is presented. / A Dissertation submitted to the Department of Physics in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Fall Semester 2015. / August 12, 2015. / Includes bibliographical references. / Ingo Wiedenhöver, Professor Directing Dissertation; Tomasz Plewa, University Representative; Alexander Volya, Committee Member; Paul Cottle, Committee Member; Nicholas Bonesteel, Committee Member.

Vector and tensor analyzing powers $(iT\sb{11},\ T\sb{20},\ T\sb{21},$ and $T\sb{22}$) for $\rm\sp6\vec{Li}$ + $\sp{12}$C elastic and inelastic scattering are presented for a $\rm\sp6\vec{Li}$ bombarding energy of 30 MeV over the center of mass angular range 15$\sp\circ$-138$\sp\circ.$ High quality data over the large angular range provided a rigorous test for the nuclear scattering models. / Optical model calculations of the elastic scattering included central, spin-orbit, tensor, and angular momentum dependent potential terms. These calculations showed that the vector and tensor analyzing powers are sensitive to the presence of a spin-orbit potential term and the need for a tensor potential term to describe $T\sb{21}.$ / Previously measured cross sections along with the present analyzing power measurements were analyzed with a coupled channels method. The double folding model was employed for the real part of the nuclear scattering potential. Five channels were involved in the calculations which were the elastic, $\rm\sp{12}C(2\sp+,\ 4.44\ MeV),\ \sp{12}C(3\sp-,\ 9.64\ MeV),\ \sp6Li(3\sp+,\ 2.18\ MeV),$ and $\rm\sp6Li(2\sp+,$ 4.31 MeV) states. Projectile excitation was investigated by the inclusion of the $\rm\sp6Li\ 3\sp+$ and $2\sp+$ states and was found to be a contributing factor to the tensor analyzing powers. The present work is the first polarization measurements made where there exists previously measured projectile excitation cross sections. These cross sections provide a measure of the coupling strength needed for these states in the coupled channels analysis. Also the spin-orbit potential was found to provide the dominant contribution to the inelastic $iT\sb{11}.$ / Source: Dissertation Abstracts International, Volume: 55-04, Section: B, page: 1490. / Major Professor: Kirby W. Kemper. / Thesis (Ph.D.)--The Florida State University, 1994.

A present mystery in nuclear physics is the location of mirror states in the nuclei $\sp9$B, $\sp9$Be, with much less known about $\sp9$B. A measurement of the location of the low lying states of $\sp9$B was made using the reaction $\rm\sp6 Li(\sp6 Li,\sp9 B)t$ at a bombarding energy of 56 MeV. These states have not been previously observed due to their expected large width and small populations which leave them masked by other strongly populated states in the same energy region. Resonant Particle Decay Spectroscopy was applied to the $\alpha{+}\alpha{+}\rm p$ particles resulting from the decay of $\sp9$B. With this technique, relative energy spectra could be constructed that had low background because states were removed which decay via other reaction channels. In addition, singles spectra for both $\sp9$B and $\sp9$Be were obtained to provide evidence for the population of the excited states in the mirror nuclei $\sp9$B and $\sp9$Be. The relative energy spectra of $\sp9$B were analyzed using the one-level R-matrix approximation, in which the reduced widths of the excited states were taken from $\sp9$Be data, and the excitation energies of the unknown states and the formation factors were used as adjustable parameters in this fit. The previously unresolved ${1\over 2}\sp+$ state of $\sp9$B was clearly found, and it lies at an excitation energy $\le$1.6 MeV. In addition, there was evidence that the location of the ${1\over 2}\sp-$ state, which must exist in $\sp9$B, lies between 2.0 and 2.5 MeV in excitation. / Source: Dissertation Abstracts International, Volume: 55-08, Section: B, page: 3379. / Major Professor: Kirby W. Kemper. / Thesis (Ph.D.)--The Florida State University, 1994.

High spin states in $\sp{77}$Kr were populated using the $\sp{48}$Ti($\sp{32}$S,2pn)$\sp{77}$Kr reaction with a 106 MeV $\sp{32}$S beam from the Florida State University Tandem-LINAC accelerator. Three Compton-suppressed Ge detectors at 95$\sp\circ$ and one at 18$\sp\circ$ were used to determine $\gamma - \gamma$ coincidences, directional correlation ratios and Doppler-shift attenuation lifetimes. Seven new transitions were added, extending the level scheme to new spin states of (45/2$\sp+$) and 27/2$\sp-;$ twenty-two new lifetimes were measured. High spin states of $\sp{75}$Se were investigated using the $\sp{59}$Co($\sp{19}$F,2pn)$\sp{75}$Se reaction at 55 MeV. Four Compton-suppressed detectors were used in this experiment; three placed at 90$\sp\circ$ and one at 25$\sp\circ$, for the determination of DCO ratios and lifetimes. Spin assignments were confirmed and mixing ratios were determined by measuring angular distributions with the reaction $\sp{71}$Ga($\sp7$Li,3n)$\sp{75}$Se at 25 MeV. Parity assignments were made from polarization measurements using the same reaction. The positive-parity band in $\sp{75}$Se has been extended to $I\sp\pi$ = 29/2$\sp+$ and the unfavored signature band has been identified. The negative-parity band has been extended to $I\sp\pi$ = 19/2$\sp-$. Eleven new lifetimes were measured. A cranking model analysis was performed for both $\sp{77}$Kr and $\sp{75}$Se. A band crossing due to proton alignment was observed for the first time in $\sp{75}$Se. Quadrupole moments extracted from lifetimes, indicated significant collective behavior for both $\sp{77}$Kr and $\sp{75}$Se. The staggering of transition strengths coupled with signature splitting revealed the data to be consistent with largely a triaxial shape for $\sp{75}$Se and a more prolate shape for $\sp{77}$Kr. / Source: Dissertation Abstracts International, Volume: 54-03, Section: B, page: 1462. / Major Professor: Sam Tabor. / Thesis (Ph.D.)--The Florida State University, 1993.

The reactions, $\rm\sp{12}C(\sp7Li,\alpha)\sp{15}N$ and $\rm\sp7Li(\sp{12}C,\sp{15}N\to\alpha$ + $\sp{11}B)\alpha$ at E$\sb{\rm cm}$ = 33.2 MeV, are used to measure the alpha-particle decay branching ratio, $\Gamma\sb\alpha/\Gamma,$ of states in $\sp{15}$N produced at several excitation energies, $\rm E\sb{x}(\sp{15}N).$ Resonant Particle Decay Spectroscopy is applied to the sequential reaction to identify $\sp{15}$N states and construct their alpha-particle angular correlations from the kinematic reconstruction of the relative kinetic energy of the $\sp{15}$N break-up products $(\alpha$ and $\sp{11}$B) detected in coincidence by use of two position sensitive detectors. It is shown that the symmetry observed in these correlations implies azimuthal isotropy, so that integration can be accomplished to yield $\Gamma\sb\alpha/\Gamma$ in conjunction with the measured $\sp{15}$N production cross sections. For excited states at $\rm E\sb{x}(\sp{15}N)$ = 11.44, 12.56, 13.01, 13.18, 13.83 and 14.11 MeV, the measured values of $\Gamma\sb\alpha/\Gamma$ are 0.07 $\pm$ 0.01, 0.60 $\pm$ 0.04, 0.84 $\pm$ 0.09, 0.34 $\pm$ 0.04, 0.37 $\pm$ 0.09 and 0.31 $\pm$ 0.06 respectively (absolute uncertainty is $\sim$15%). Reduced widths of some of these states are calculated under limiting approximations. / Spectral analysis also yields: (a) New excited states at $\rm E\sb{x}(\sp{15}N)$ = 12.67, 12.83, 15.15 and 22.58 MeV, (b) confirmation of previously questioned states at $\rm E\sb{x}(\sp{15}N)$ = 15.87 and 21.37 MeV, (c) previously unknown alpha-particle decays for 17 excited states and (d) correction of previously reported energy widths for states at $\rm E\sb{x}(\sp{15}N)$ = 16.20, 16.46, 17.12, and 20.95 MeV. Probable spin-parity values are proposed for several $\sp{15}$N states based on a DWBA analysis carried out for the angular distributions of the $\rm\sp{12}C(\sp7Li,\alpha)\sp{15}N$ reaction and the best theoretical descriptions of the alpha-particle angular correlations of the sequential reaction. / Source: Dissertation Abstracts International, Volume: 54-03, Section: B, page: 1462. / Major Professor: Neil R. Fletcher. / Thesis (Ph.D.)--The Florida State University, 1993.