Source: Dissertation Abstracts International, Volume: 40-07, Section: B, page: 3236. / 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.

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.

Excited states in $\sp{82}$Y have been investigated via the $\rm \sp{58}Ni(\sp{28}Si,\ 3{\it pm\/})\sp{82}Y$ and $\rm \sp{58}Fe(\sp{29}Si,\ {\it p\/}2{\it n\/})\sp{82}Y$ reactions using beams provided by the Florida State University Tandem-LINAC with energies of 95 to 135 MeV. Particle-$\gamma$ coincidences with a full-sphere charged particle detector and an excitation curve were employed to assign $\gamma$ rays to $\sp{82}$Y. The full sphere charged particle detector was developed and tested as a part of this dissertation project. The $\rm \sp{56}Fe(\sp{29}Si,\ {\it p\/}2{\it n\/})\sp{82}Y$ reaction at 95 MeV was employed to measure $\gamma$-$\gamma$ coincidences with 5 Compton-suppressed Ge detectors. Lifetimes in the ns and ps time ranges were measured using direct timing and the Doppler-shift attenuation method. A level scheme with 39 states was constructed up to tentative spins and parities of (15$\sp-)$ and (21$\sp+).$ In the positive parity yrast band a signature inversion and a phase reversal in the signature at $I = 10\ \hbar$ were observed. The B(M1) strengths in this band alternate with signature between about 0.1 and 1.0 $\mu\sbsp{N}{2}.$ The B(E2) strengths are in good agreement with those predicted by Hartree-Fock-Bogolyubov calculations. Particle-rotor calculations indicate a prolate or triaxial shape for the positive parity band. / Source: Dissertation Abstracts International, Volume: 54-04, Section: B, page: 2033. / Major Professor: Samuel L. Tabor. / Thesis (Ph.D.)--The Florida State University, 1993.

Cross sections for incomplete fusion followed by fission have been measured for the reaction ($\sp{16}$O + $\sp{232}$Th) at 140 MeV. In plane and out of plane measurements were made of cross sections for beamlike fragments in coincidence with fission fragments. The beamlike fragments were detected with the Florida State large acceptance Bragg curve spectrometer. The detector was position sensitive in the polar direction. The beamlike particles observed in coincidence with fission fragments were He, Li, Be, B, C, N and O. Fission fragments were detected by three surface barrier detectors using time of flight for particle identification. The reaction cross section due to incomplete fusion is 747 $\pm$ 112 mB, or 42% of the total fission cross section. The strongest incomplete fusion channels were the helium and carbon channels. The average transferred angular momentum for each incomplete fusion channel was calculated using the $Q\sb{opt}$ model of Wilczynski, and the angular correlation was calculated using the saddle point transition state model. The K distribution was determined from the Rotating Liquid Drop model. The theoretical angular distributions were fitted to the experimental angular distributions with the angular momentum J and the dealignment factor $\alpha\sb{o}$ as free parameters. The fitted parameter J was in excellent agreement with the $Q\sb{opt}$ model predictions. The conclusions of this study are that the incomplete fusion cross section is a large part of the total cross section, and that the saddle point transition state model adequately describes the observed angular correlations for fission following incomplete fusion. / Source: Dissertation Abstracts International, Volume: 54-07, Section: B, page: 3682. / Major Professor: John D. Fox. / Thesis (Ph.D.)--The Florida State University, 1993.

The coincidence cross sections of the reactions $\sp{27}$Al($\sp{16}$O, $\sp{12}$C $\alpha$) and $\sp{27}$Al($\sp{16}$O, C p) at 133 MeV beam energy for laboratory angles out to $\Theta\sb{C} = 32\sp\circ$ and $\Theta\sb\alpha$ or $\Theta\sb{p} = 60\sp\circ$ were measured at 370 different combinations of $\Theta$ and relative $\Phi$ angles between detectors. The coincidence cross sections were integrated to calculate the total three body final state cross section over this angle range. The $\sp{27}$Al($\sp{16}$O, C p) cross section due to the sequential breakup of several intermediate states of $\sp{13}$N and $\sp{14}$N was determined. The incomplete fusion process, $\sp{16}$O + $\sp{27}$Al $\to$ $\sp{12}$C + $\sp{31}$P$\sp*$ $\to$ $\sp{12}$C + $\alpha$ + $\sp{27}$Al, was found to dominate for $\Theta\sb\alpha \ge 50\sp\circ$ by kinematic arguments. The total cross section and the cross section for $\Theta\sb\alpha \le 40\sp\circ$ for the incomplete fusion reaction, $\sp{16}$O + $\sp{27}$Al $\to$ $\sp{12}$C + $\sp{31}$P$\sp*$ $\to$ $\sp{12}$C + $\alpha$ + $\sp{27}$Al, were calculated using the experimental cross section for $\Theta\sb\alpha \ge 50\sp\circ$ and a parameterized angular distribution for the emission of the $\alpha$ particle from the $\sp{31}{\rm P}\sp*$ intermediate state. The total cross section for the sequential breakup process, $\sp{16}$O + $\sp{27}$Al $\to$ $\sp{16}$O$\sp*$ + $\sp{27}$Al $\to$ $\sp{12}$C + $\alpha$ + $\sp{27}$Al, was determined by subtracting the incomplete fusion cross section for $\Theta\sb\alpha \le 40\sp\circ$ from the experimental cross section for $\Theta\sb\alpha \le 40\sp\circ,$ since there was no evidence of significant contributions from other reaction processes. / The sequential breakup process $\sp{27}$Al + $\sp{16}$O $\to$ $\sp{27}$Al + $\sp{16}$O$\sp*$ $\to$ $\sp{27}$Al$\sb{gs}$ + $\sp{12}$C$\sb{gs}$ + $\alpha$ was modeled by using a distorted wave Born approximation calculation to generate amplitudes for producing states of the $\sp{16}{\rm O}\sp*$ observed for this reaction in other experiments and then calculating the angular distribution of the decay products after their breakup into the laboratory frame. The model generated cross section for this process was significantly larger than that observed experimentally and was more forward peaked for the $\sp{12}$C angle. / Source: Dissertation Abstracts International, Volume: 55-01, Section: B, page: 0133. / Major Professor: Lawrence C. Dennis. / Thesis (Ph.D.)--The Florida State University, 1993.