| This dissertation presents a study of fission dynamics and time scales for the following reactions; 133 MeV 16O + 208Pb, 104 MeV 4He + 209Bi, 133 MeV 16O + 176Yb, and 104 MeV 4He + 188Os. Two disparate means were utilized: fission coincidence measurements of pre- and post-scission neutrons and of gamma rays. These measurements were accomplished simultaneously and analyzed similarly, so as to minimize experimental differences and systematic model-dependent biases.; Fission fragments were detected via large x-y position-sensitive parallel plate avalanche counters (PPACs) mounted in compact geometry to maximize their geometric efficiency. The fission fragment emission angles and relative velocities were used to reconstruct masses via standard kinematics.; The gamma rays were detected by 144 BaF2 crystals from the U. S. Barium Fluoride Array (BFA). These detectors were arranged into two pods of 72 crystals placed at backward angles to minimize the neutron flux. The high granularity made it possible to reconstruct the event showers to obtain the total energy deposited by each detected gamma ray. The reconstructed energy spectra were then analyzed in the giant dipole resonance (GDR) region with the aid of statistical model calculations, giving the time scales for fission, tfissg . From the gamma-ray data, the time scales obtained for the reactions 16O + 208Pb, 4He + 209Bi, and 16O + 176Yb were tfissg = 67 +/- 10 zs, 45 +/- 9 zs, and 84 +/- 16 zs, respectively.; Neutrons were detected by 8 liquid scintillator detectors from the DEMON Array, which were positioned around the target to ensure separation of neutrons and gamma rays and to obtain the multiplicities of pre- and post-scission neutrons. With the help of statistical model calculations, these multiplicities were also analyzed to extract the fission time scales, tfissn . From the neutron data, the time scales obtained for the reactions 16O + 208Pb, 4He + 209Bi, 16O + 176Yb, and 4He + 188Os were tfissn = 105 +/- 10 zs, 72 +/- 7 zs, 112 +/- 12 zs, and 31 +/- 4 zs, respectively. |
