Elastic scattering ${}_{}{}^{10}{}_{}{}^{}\mathrm{B}$${(}^{14}$N${,}^{14}$N${)}^{10}$B angular distributions were measured at four bombarding energies: 38.1, 42.0, 46.0, and 50.0 MeV. By detecting the recoiling target nuclei complete angular distributions ranging from ${\theta }_{\mathrm{c}.\mathrm{m}.\mathrm{}=14\mathrm{}}$° to 176° were obtained. Normalized cross sections, σ/${\sigma }_R$ were found to be larger than 0.1 for angles greater than 160°. The anomalous behavior at the backward angles is interpreted as partially due to an elastic α-transfer process. The deduced spectroscopic factor for the configuration of an alpha particle coupled to a ${}_{}{}^{10}{}_{}{}^{}\mathrm{B}$ core in the ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ ground state is $S_4$=0.65±0.10. The compound elastic contribution is about 20% of the calculated transfer cross section at θ=176° and accounts for 3% of the experimental cross section at this angle.

The hypernucleus formation probability in nuclear collisions is formulated with a coalescence model and is calculated for p+Ne and Ne+Ne collisions at 2.1 GeV/nucleon and 5 GeV/nucleon. It is found that the probability of the hypernucleus formation at 5 GeV/nucleon is about a few times larger than at 2.1 GeV/nucleon and also that the probability of the hypernucleus formation in the Ne+Ne collisions is a few times larger than that in the p+Ne collisions. The cross section of Λ-hypernucleus formation is of the order of μb in the Ne+Ne collisions at 5 GeV/nucleon. The formation probability of multi-Λ hypernucleus is also discussed.

A new heavy-ion collision model which couples ideal, relativistic hydrodynamics with dynamical pions is described. The collective flow predicted by the model is shown to compare favorably to results obtained in earlier hydrodynamic calculations using quite different numerical methods. Discrepancies with experimental data are discussed, as are possible resolutions of the differences. Pion multiplicities resulting from the model are presented along with their experimental implications. Extensions to the model are discussed as well.

The reaction ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$${(}^6$Li${,}^6$Li’${)}^{12}$C*${(}^6$Li,d${)}^{16}$(α${)}^{12}$C proceeding via the quasibound $4_2^{+}$ ($E^{\mathrm{*}}$=11.09 MeV) state of ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ has been suggested to proceed via a two-step process. We reinvestigate this case. Computing the angular correlation function W(${\Omega }_d$,${\Omega }_{\alpha }$) it is confirmed that the previous suggestions are indeed correct. Furthermore, our results indicate that the comparison of calculated W(${\Omega }_d$,${\Omega }_{\alpha }$) with experimental phase shifts may be used as a detector for two-step processes.

The optimal polynomial theory of Cutkosky, Deo, and Ciulli has been tested for its use in a multienergy phase-shift analysis of pp scattering data below $T_{\mathrm{lab}=350\mathrm{}}$ MeV. The power of the optimal polynomial theory to predict higher partial wave phase parameters is investigated also for a realistic potential model; the Nijmegen potential. It is seen that the optimal polynomial theory has indeed predictive power whenever the phase parameters do not decrease too rapidly as a function of the orbital angular momentum. For a high-quality phase-shift analysis, the optimal polynomial theory does not predict F and G waves well enough. Therefore, these have to be parametrized. The predictive power of the optimal polynomial theory is then only used for higher partial waves. It appears that the Nijmegen potential tail contains valuable physical information beyond the optimal polynomial theory.

The effects of charge-symmetry breaking of nuclear forces can be observed in neutron-proton elastic scattering as a difference between neutron and proton analyzing powers. A formalism has previously been developed and applied to compute these effects in terms of electromagnetic interactions, one-boson exchange potentials, the two-pion exchange potential, and possible quark effects. The results were found to be in agreement with the one existing measurement. Here we extend this work and study in detail how these charge-symmetry breaking predictions vary with the particular choice for the nucleon-nucleon force. We compare predictions for Reid soft-core, Paris, coordinate-space Bonn, and hybrid quark-meson potentials. We show in particular that charge-symmetry breaking measurements can place strong restrictions on models of the nucleon-nucleon interaction.

Distorted wave impulse approximation predictions are made for quasifree (π,πN) nucleon knockout reactions on polarized nuclear targets. The case of $J_A$=(1/2 targets is considered in detail with particular reference to ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$. It is shown, for this case, that three terms, having somewhat different physical origins, contribute to the spin-up/spin-down asymmetry.

A schematic model is devised to account for the charged track pattern in antiproton nucleus annihilation at low momenta. The ejection mechanism is assumed to correspond to a clan picture, where the ancestors are pions. Good agreement is obtained for multiplicity distributions, in neon and in emulsion, and in particular for the very strong correlation observed in neon between negative pions and the total number of charged tracks.

We present new results for inclusive electron scattering in ${}_{}{}^2{}_{}{}^{}\mathrm{H}$, ${}_{}{}^3{}_{}{}^{}\mathrm{He}$, and ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ in order to test the reaction mechanism for quasielastic scattering as a function of nuclear density. Radiative corrections are applied to the cross section data and Rosenbluth separations are made for three-momentum transfer (q) between 300 and 600 MeV/c. The A and q dependencies of the data are discussed for the quasielastic peak and the region between the quasielastic peak and the Δ resonance peak (dip region). Comparisons are shown between the data and models based on a quasielastic reaction mechanism. The models give a reasonable representation of the peak at q∼500 MeV/c, but the longitudinal data for the helium isotopes are significantly suppressed with respect to the quasielastic predictions at q<400 MeV/c. None of the calculations predict the rapid rise with q and A in the transverse strength in the dip region seen in the data. A significant breakdown of the quasielastic picture is seen in the data as A increases from 2 to 4.

The relativistic nuclear shell model with large scalar and time-component vector potentials predicts very strongly bound negative-sea states. Such states may be absent in alternative versions of the model which contains a tensor term. The process (γ,pp¯) in the presence of a nucleus could form a highly excited p¯-nucleus with gamma ray energy less than 2M. The predicted cross section for γ${+}^{16}$O${\to }_{{}_{p¯}{}^{15}{}_{}{}^{}\mathrm{N}+\mathit{p}}$ has a threshold 1.2 GeV and rises to about 5 μb by 1.6 GeV.

Differential ranges at five angles to the beam have been measured for 23 fragments, ranging from ${}_{}{}^{47}{}_{}{}^{}\mathrm{Ca}$ to ${}_{}{}^{143}{}_{}{}^{}\mathrm{Ce}$, produced in the interaction of ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$ with 400 GeV protons. Energy spectra obtained from the data show evidence for the presence or two components, which can be attributed to deep spallation and to fragmentation or fission. The spectra have been compared with a thermal model, used to test the two-step model of high-energy reactions, subjected to an invariant cross section analysis, and compared with the predictions of the Hüfner fast breakup model.

The weak ΛNρ coupling is calculated by using a pole model and information from weak nonleptonic and radiative decays. Our results improve previous evaluations of the potential for the transition ΛN→NN and can be used as a clue to a better understanding of nonmesonic decay of heavy Λ hypernuclei.

By extending a coupled channels model which has proven successful in describing the reaction pp→${\pi }^{+}$d, we make predictions for charge symmetry breaking effects in the reaction np→d${\pi }^0$. We find that nucleon and delta mass differences at vertices where pions are emitted or absorbed are important (as for np elastic scattering). However, η-${\pi }^0$ mixing is also important in pion production. We predict forward-backward asymmetries in the pion production differential cross section as large as 1% (for laboratory energies below 800 MeV). The asymmetries induced in polarization observables are small.

The hypernuclear systems ${\Sigma }^{\mathrm{-}}$${+}^{11}$B and ${\Sigma }^{\mathrm{-}}$${+}^6$He were produced by the ($K^{\mathrm{-}}$,${\pi }^{+}$) reaction on targets on ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ (graphite) and ${}_{}{}^7{}_{}{}^{}\mathrm{Li}$ using 715 MeV/c incident kaons. Spectra were measured at reaction angles of 4° and 12° to investigate the momentum transfer dependence. A decay detector surrounded the target to provide a decay mode tag. Data were analyzed with and without this tag. The resulting spectra for the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ target are similar to previous results with the exception that the narrow structure reported in the stopped $K^{\mathrm{-}}$ experiments is not confirmed. The spectra do show enhancements over phase space near the thresholds of the Σ plus core hole states which are created when a proton in the target is converted into a Σ. The decay mode cut shows a correlation between sigma-lambda conversion and this structure. No evidence of narrow states in either hypernucleus is observed in either the tagged or untagged data.

The microscopic (α+3N+N)+Λ cluster model is applied to achieve a unified understanding of the ${}_{\mathrm{\Lambda }}{}^9{}_{}{}^{}\mathrm{Be}$ hypernucleus in the energy region up to $E_{\Lambda }$≃20 MeV. The eigenstates of ${}_{\mathrm{\Lambda }}{}^9{}_{}{}^{}\mathrm{Be}$ consist of low-lying cluster states with ${}_{}{}^8{}_{}{}^{}\mathrm{Be}$ (α+α)+Λ structure and high-lying core-excited states with ${}_{}{}^8{}_{}{}^{}\mathrm{*}$ (α+α)+Λ structure (* denotes the intrinsic) excited state). With use of the ${}_{\mathrm{\Lambda }}{}^9{}_{}{}^{}\mathrm{Be}$ wave functions obtained, the production cross sections of ${}_{\mathrm{\Lambda }}{}^9{}_{}{}^{}\mathrm{Be}$ through the ($K^{\mathrm{-}}$ in-flight,${\pi }^{\mathrm{-}}$), (${\pi }^{+}$,$K^{+}$), and ($K^{\mathrm{-}}$ stopped,${\pi }^{\mathrm{-}}$) reactions are evaluated. Each reaction process shows its own selective population of states and hence contributes to the comprehensive test of the theoretical predictions. A quantitative understanding is obtained for the three-peak structure observed in the ($K^{\mathrm{-}}$ in-flight,${\pi }^{\mathrm{-}}$) reaction experiment. The predicted (${\pi }^{+}$,$K^{+}$) excitation function is in good agreement with recent experimental data, and for the first time genuine hypernuclear states came into observation.

Recent ${\pi }^{\pm }$ scattering data at 20 and 30 MeV are analyzed semiphenomenologically and phenomenologically. Although the present method of extrapolation from pionic atoms to scattering is not entirely satisfactory, the scattering data presently available appear to show effects of the pionic atom anomaly.

The reaction ${\pi }^{\mathrm{-}}$p→γn has been studied at $T_{\pi }$=45.6, 62.2, 76.4, 91.7, 106.8, and 121.9 MeV for nine laboratory angles between 30° and 140°. The differential cross section measurements have angle to angle errors of about 4% with an additional 3% normalization error. The results are typically a factor of 2 more accurate than previous radiative capture data and are more reliable than cross sections obtained from the reverse reaction γd→${\pi }^{\mathrm{-}}$${\mathrm{pp}}_s$. The data are compared with recent multipole analyses, various calculations, as well as previous data, and the best agreement is with the Tokyo multipole analysis.

The reaction ${\pi }^{\mathrm{-}}$p→${\pi }^0$n has been studied using a large NaI crystal to detect the decay γ rays of the ${\pi }^0$, at pion beam energies of 45.6, 62.2, 76.4, 91.7, 106.8, and 121.9 MeV. The NaI was set at nine different laboratory angles, but at almost every angle the angular distribution of the ${\pi }^0$ can be derived from the energy spectrum of the γ rays. The results are compared with recent phase-shift analyses and with various calculations. New values of the charge exchange scattering length are derived.

We report on the pulse height spectrum observed with a CdTe detector in a low-background shield. The spectrum is dominated by the $T_{1/2}$∼${10}^{16}$ yr ${\beta }^{\mathrm{-}}$ decay of ${}_{}{}^{113}{}_{}{}^{}\mathrm{Cd}$. Limits are set on the double beta decay of the isotopes ${}_{}{}^{106}{}_{}{}^{}$,114,116Cd and ${}_{}{}^{128}{}_{}{}^{}$,130Te, and the prospects for a more sensitive search for this mode of decay are discussed.

Measurements have been made of the gamma ray branching ratios for the decay of the lowest isobaric analog states of ${}_{}{}^{71}{}_{}{}^{}\mathrm{Ge}$ and ${}_{}{}^{81}{}_{}{}^{}\mathrm{Kr}$. These states could be populated by high-energy neutrinos in gallium- and bromine-based detectors. Although these states are unbound to particle decay, all channels with significant penetrabilities are isospin forbidden, so that gamma decay is a possibility. Our results indicate that these states decay mainly by neutron emission and therefore contribute very little to detection sensitivities for ${}_{}{}^{71}{}_{}{}^{}\mathrm{Ga}$ and ${}_{}{}^{81}{}_{}{}^{}\mathrm{Br}$.