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Proton and {alpha}-particle energy spectra were measured in coincidence with evaporation residues from 252 and 295 MeV {sup 58}Ni+{sup 112}Sn fusion reactions. Residues were separated from the beam using an electrostatic deflector and detected with surface barrier detectors. Light charged particles were detected with arrays of NaI detectors. Statistical model calculations based on standard parameter choices reproduce the spectra from the cold, low spin {sup 170}Pt{sup *} system. The effects of employing different methods of calculating transmission coefficients were explored. The optical model, ingoing wave boundary condition model, and a simple one-dimensional barrier penetration model from a fusion systematics analysis produce comparable satisfactory predictions. The Hill-Wheeler approximation for transmission coefficients gives unrealistic results for protons.

A computer pattern recognition system, RAPID, has been used to study the spontaneous motor activity of Sprague-Dawley rats. This system produces a large number of measures of the activity of control and experimental groups in any given study. The large number of measures involved presents a problem when one attempts to decide whether the behavioral activity of the exposed group differs from that of the control group. Extensive Monte Carlo studies have been performed in an attempt to develop and validate a simple statistic to be used in such decisions.

The one-neutron pickup reaction $^{235}\mathrm{U}$${(}^{206}$Pb${,}^{207}$Pb${)}^{234}$U at a laboratory energy of 1394 MeV was used to investigate the influence of collective motion at high spin on the single-particle nature of transfer reactions in the actinide region. Deexcitation \ensuremath{\gamma} rays were measured using a particle-particle-\ensuremath{\gamma} triple-coincidence method. The decay scheme of the reaction products was identified using p-\ensuremath{\gamma}-\ensuremath{\gamma} coincidences. Rotational states up to ${28}^{+}$(${30}^{+}$) were seen in $^{234}\mathrm{U}$. A comparison of rotational state population in both the p--\ensuremath{\gamma}-ray singles and the p-\ensuremath{\gamma}-\ensuremath{\gamma} coincidences is also made between data from the above reaction and from the reaction $^{235}\mathrm{U}$${(}^{58}$Ni${,}^{59}$Ni${)}^{234}$U (${\mathit{E}}_{\mathrm{lab}}$=325 MeV). For each system, angular distributions for both inelastic excitation and transfer are presented and one-neutron transfer reaction cross sections as well as grazing angles have been extracted. The reaction cross sections are compared to a recent semiclassical calculation based on ${\mathit{Q}}_{\mathit{g}\mathit{g}}$ systematics. The present study demonstrates the feasibility of using heavy-ion-induced transfer reactions for spectroscopic studies.

High-energy photon yields from the reactions [sup 12]C+[sup 112,124]Sn at 10 MeV/nucleon have been measured. The ratio of cross sections ([ital E][sub [gamma]][ge]30 MeV)[sigma]([sup 124]Sn)/[sigma]([sup 112]Sn) is 1.6[plus minus]0.2, which is larger than expected within the equal-participant model. The elementary [ital n]-[ital p]-[gamma] cross section is evaluated within the neutral scalar [sigma] meson exchange model, and implemented into a BUU code. The results of the BUU calculation suggest that the high-energy [gamma]-ray yield differences for the two Sn isotopes arise from the differences in nucelon phase-space distributions. The sensitivity of the high-energy photon production to the initial phase-space conditions is explored.

The heavy‐ion one‐neutron pickup reaction 239Pu(90Zr,90Zr’)239Pu’ (Elab=500 MeV) were used to study the rotational level schemes of 238Pu and 239Pu, respectively. Spectroscopic information on 238Pu is presented and discussed.

A large lead glass \ifmmode \check{C}\else \v{C}\fi{}erenkov counter has been used to measure the energy spectrum of gamma rays resulting from neutral pions produced in proton-proton collisions. A liquid hydrogen target was bombarded with protons of 447 Mev, 415 Mev, and 397 Mev. Gamma rays emitted at 90\ifmmode^\circ\else\textdegree\fi{} to the incident proton beam were detected by a counter telescope comprised of an anticoincidence counter, a $\frac{1}{8}$-in. lead converter, two coincidence counters, and the lead glass counter. Pulses from the lead glass counter were fed through a gating circuit into a one-hundred channel pulse-height analyzer. The three pulse-height spectra obtained have been compared with those predicted from the phenomenological theory, to estimate the contributions of the various possible final angular momentum states. It is found that the spectra are consistent with isotropic emission of the ${\ensuremath{\pi}}^{0}'\mathrm{s}$ in the center-of-mass system. The differential cross sections for ${\ensuremath{\pi}}^{0}$ production are 12.6\ifmmode\pm\else\textpm\fi{}2.0, 9.0\ifmmode\pm\else\textpm\fi{}1.9, and 7.4\ifmmode\pm\else\textpm\fi{}1.7 microbarns/sterad at 445, 415, and 397 Mev, respectively.

We have measured the cross sections for hyperon production in 2.7-GeV/c $\overline{p}p$ interactions. The values obtained are: $\ensuremath{\sigma}(\overline{\ensuremath{\Lambda}}\ensuremath{\Lambda})=113\ifmmode\pm\else\textpm\fi{}15 \ensuremath{\mu}\mathrm{b}, \ensuremath{\sigma}({\overline{\ensuremath{\Sigma}}}^{0}\ensuremath{\Lambda})+\ensuremath{\sigma}(\overline{\ensuremath{\Lambda}}{\ensuremath{\Sigma}}^{0})=66\ifmmode\pm\else\textpm\fi{}13 \ensuremath{\mu}\mathrm{b},$ $\ensuremath{\sigma}({\overline{\ensuremath{\Sigma}}}^{0}{\ensuremath{\Sigma}}^{0})l15 \ensuremath{\mu}\mathrm{b}, \ensuremath{\sigma}({\overline{\ensuremath{\Xi}}}^{0}{\ensuremath{\Xi}}^{0})=\ensuremath{\le}2.8 \ensuremath{\mu}\mathrm{b}(90% \mathrm{confidence})$ $\ensuremath{\sigma}({\overline{\ensuremath{\Sigma}}}^{\ensuremath{-}}{\ensuremath{\Sigma}}^{+})=30.7\ifmmode\pm\else\textpm\fi{}9.4 \ensuremath{\mu}\mathrm{b}, \ensuremath{\sigma}({\overline{\ensuremath{\Sigma}}}^{+}{\ensuremath{\Sigma}}^{\ensuremath{-}})=1.0\ifmmode\pm\else\textpm\fi{}5.4 \ensuremath{\mu}\mathrm{b} (\mathrm{large}\mathrm{error}\mathrm{resulting}\mathrm{from}\mathrm{subtraction}),$ $\ensuremath{\sigma}({\overline{\ensuremath{\Xi}}}^{+}{\ensuremath{\Xi}}^{\ensuremath{-}})=\ensuremath{\le}1.8 \ensuremath{\mu}\mathrm{b} (90% \mathrm{confidence}), \ensuremath{\sigma}(\overline{\ensuremath{\Lambda}}\ensuremath{\Lambda}{\ensuremath{\pi}}^{0})=65\ifmmode\pm\else\textpm\fi{}25 \ensuremath{\mu}\mathrm{b},$ $\ensuremath{\sigma}({\overline{\ensuremath{\Sigma}}}^{\ensuremath{-}}\ensuremath{\Lambda}{\ensuremath{\pi}}^{+}+\mathrm{c}.\mathrm{c}.)=25.9\ifmmode\pm\else\textpm\fi{}10.1 \ensuremath{\mu}\mathrm{b}, \ensuremath{\sigma}({\overline{\ensuremath{\Sigma}}}^{\ensuremath{-}}{\ensuremath{\Sigma}}^{0}{\ensuremath{\pi}}^{+}+\mathrm{c}.\mathrm{c}.)=2.9\ifmmode\pm\else\textpm\fi{}2.9 \ensuremath{\mu}\mathrm{b} (\mathrm{one}\mathrm{event}),$ $\ensuremath{\sigma}({\overline{\ensuremath{\Sigma}}}^{+}\ensuremath{\Lambda}{\ensuremath{\pi}}^{\ensuremath{-}}+\mathrm{c}.\mathrm{c}.)=6.6\ifmmode\pm\else\textpm\fi{}3.9 \ensuremath{\mu}\mathrm{b}, \ensuremath{\sigma}({\overline{\ensuremath{\Sigma}}}^{+}{\ensuremath{\Sigma}}^{0}{\ensuremath{\pi}}^{\ensuremath{-}}+\mathrm{c}.\mathrm{c}.)=3.7\ifmmode\pm\else\textpm\fi{}2.6 \ensuremath{\mu}\mathrm{b},$ $\ensuremath{\sigma}({\overline{\ensuremath{\Sigma}}}^{\ensuremath{-}}{\ensuremath{\Sigma}}^{+}{\ensuremath{\pi}}^{0})=\ensuremath{\le}3.6$ \ensuremath{\mu}b (90% confidence), $\ensuremath{\sigma}(\overline{\ensuremath{\Lambda}}\ensuremath{\Lambda}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}})=3\ifmmode\pm\else\textpm\fi{}2$ \ensuremath{\mu}b, and $\ensuremath{\sigma}(\ensuremath{\Lambda}{K}^{+}\overline{p})=2.3\ifmmode\pm\else\textpm\fi{}2.3$ \ensuremath{\mu}b (one event). The ratios of the cross sections for the two-body final states have been compared with predictions of $S{U}_{3}$ and are in good agreement with the process being dominated by the exchange of an antisymmetric octet in the $t$ channel. The angular distributions of $\overline{\ensuremath{\Lambda}}\ensuremath{\Lambda}$, ${\overline{\ensuremath{\Sigma}}}^{\ensuremath{-}}{\ensuremath{\Sigma}}^{+}$, and $\overline{\ensuremath{\Lambda}}\ensuremath{\Lambda}{\ensuremath{\pi}}^{0}$ final states clearly show the peripheral nature of these interactions. The differential cross section data for the interaction $\overline{p}p\ensuremath{\rightarrow}\overline{\ensuremath{\Lambda}}\ensuremath{\Lambda}$ have been compared with parametric equations and three absorption models. Good fits to the data have been achieved with each of these equations or models.

We report results on the reactions $\overline{p}+p\ensuremath{\rightarrow}K+\overline{K}+n\ensuremath{\pi}$ ($n=1, 2, \ensuremath{\cdots}$) at 2.7 GeV/c. The cross section for this process is estimated to be 4.1\ifmmode\pm\else\textpm\fi{}0.6 mb. Comparison of 2.7-GeV/c partial cross sections with data at 3.0 and 3.7 GeV/c indicates that these partial cross sections either are relatively constant or slowly decrease with energy. ${K}^{*}(890)$ production is observed in all the four-, five-, and six-body final states. The production of ${\ensuremath{\rho}}^{0}$ and ${\ensuremath{\omega}}^{0}$ is also observed. The $K\overline{K}$ mass spectra show enhancements near threshold as has been seen in other $\overline{p}\ensuremath{-}p$ experiments. The present data cannot distinguish between a resonance or $S$-wave scattering-length interpretation of these enhancements. No significant evidence for resonances decaying into $K\ensuremath{\pi}\ensuremath{\pi}$ or $K\overline{K}\ensuremath{\pi}$ was observed.

The charge-exchange scattering of negative pions by liquid hydrogen was measured at 61 plus or minus 1 and 95 plus or minus 2 Mev bombarding energy. The measurements were made with a gamma spectrometer which employs a lead glass Cherenkov counter. If the charge exchange scattering cross section is expanded as a series of Legendre polynomials in the center-of-mass system of the collision, it is found that at 61 Mev, d sigma /d OMEGA = (1.00 plus or minus 0.05)STA0.613 plus or minus and at 95 Mev, d sigma /d OMEGA = (1.00 plus or minus 0.03)STA1.05 plus or minus 0.05 -- (1.15 plus or minus 0.12)P/sub 1/ (cos theta ') + (0.33 plus or minus 0.25)P/sub 2/(cos theta ')!. The total cross section for charge exchange, obtained by intteration, (is sigma /sub tot/( pi /sup -/ yields pi /sup 0/)= 7.7 plus or minus 0.6 mb at 6l Mev and sigma / sub tot / ( pi /sup -/ yields pi /sup 0/) == 13.2 plus or minus 0.8 mb at 95 Mev. A table summarizing the measurements performed at 61, 95, 128, and 150 Mev is given. (auth)

The charge exchange scattering of negative pions by liquid hydrogen has been measured at 128\ifmmode\pm\else\textpm\fi{}2 Mev bombarding energy. A lead-glass \ifmmode \check{C}\else \v{C}\fi{}erenkov counter was used to measure the energy spectrum of the gamma rays emitted in the decay of the neutral pions. The gamma rays were detected at four angles relative to the incident beam: 45\ifmmode^\circ\else\textdegree\fi{}, 80\ifmmode^\circ\else\textdegree\fi{}, 116\ifmmode^\circ\else\textdegree\fi{}, and 135\ifmmode^\circ\else\textdegree\fi{}. If the charge exchange scattering cross section is expanded as a sum of Legendre polynomials which are functions of the ${\ensuremath{\pi}}^{0}$ scattering angle in the center-of-mass system, we find that $\frac{d\ensuremath{\sigma}}{d\ensuremath{\Omega}}({\ensuremath{\pi}}^{\ensuremath{-}}, {\ensuremath{\pi}}^{0})=(1.00\ifmmode\pm\else\textpm\fi{}0.04)[(2.04\ifmmode\pm\else\textpm\fi{}0.06)+(\ensuremath{-}1.61\ifmmode\pm\else\textpm\fi{}0.13){P}_{1}+(1.43\ifmmode\pm\else\textpm\fi{}0.24){P}_{2}],$ when only $s$ and $p$ waves are considered. The confidence level for the least-squares fit used to determine the coefficients inside the square brackets is 65%. The integrated cross section is ${\ensuremath{\sigma}}_{\mathrm{tot}}({\ensuremath{\pi}}^{\ensuremath{-}}, {\ensuremath{\pi}}^{0})=25.6\ifmmode\pm\else\textpm\fi{}1.3$ mb, which is in good agreement with other work.