We have measured the first complete angular correlations of α-particle emission from the ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ isoscalar giant quadrupole resonance (${\mathrm{GQ}}_0$R) following excitation by inelastic electron scattering. Analysis of these determines the ${\mathrm{GQ}}_0$R strength distribution and resolves a discrepancy between previous results from photonuclear excitation and inelastic α scattering.

Long-lived ${10}^{+}$ isomers in ${}_{}{}^{122}{}_{}{}^{}\mathrm{Sn}$ and ${}_{}{}^{124}{}_{}{}^{}\mathrm{Sn}$ have been identified among the products of ${}_{}{}^{124}{}_{}{}^{}\mathrm{Sn}$+325 MeV ${}_{}{}^{76}{}_{}{}^{}\mathrm{Ge}$ collisions. The measurements virtually complete a series of B(E2) determinations for (ν${\mathit{h}}_{11/2}$${)}^{\mathit{n}}$ states in ${}_{}{}^{116\mathrm{-}130}{}_{}{}^{}\mathrm{Sn}$, which pinpoint half filling of the ν${\mathit{h}}_{11/2}$ subshell very close to N=73. Results for these Z=50 isotopes and for the N=82 isotones are contrasted, and an enlightening comparison between the effective E2 charges observec in tin and lead isotopes is developed.

An ultrasensitive laser spectroscopic method has been developed to perform hyperfine spectroscopy of heavy-ion-induced reaction products. It is based on resonance ionization in a buffer gas cell combined with radioactive decay detection. The feasibility has been demonstrated using the β-active ${\mathrm{isotope}}^{208}$ Tl. A sensitivity of 1.3×${10}^{\mathrm{-}3}$ of the two-step resonance-ionization process via the n=17 Rydberg level has been determined, utilizing a pulsed excimer-dye-laser combination. The previously unknown nuclear magnetic moment μ${(}^{208}$Tl) = 0.292(13)${\mathrm{\mu }}_{\mathit{n}}$ (${\mathrm{\mu }}_{\mathit{n}}$ is the nuclear magneton) and a rms radius difference between ${}_{}{}^{208}{}_{}{}^{}\mathrm{Tl}$ and ${}_{}{}^{207}{}_{}{}^{}\mathrm{Tl}$ of δ〈${\mathit{r}}^2$〉=0.099(15) ${\mathrm{fm}}^2$ were deduced from the 6p ${}_{}{}^2{}_{}{}^{}$${\mathit{P}}_{1/2}$–7s ${}_{}{}^2{}_{}{}^{}$${\mathit{S}}_{1/2}$ transition.

We report the first application of an ultrasensitive detection scheme in on-line collinear-laser spectroscopy. It is based on radioactive detection of optical depopulation pumping, using state-selective charge exchange as an intermediate step. This extends the calcium isotope shift measurements beyond the ${\mathit{f}}_{7/2}$ shell closure. The extracted ${}_{}{}^{50}{}_{}{}^{}\mathrm{Ca}$ mean-square charge radius constitutes the first experimentally determined one of a short-lived neutron-rich isotope beyond the N=28 shell closure. The steep increase in radius after the doubly magic ${}_{}{}^{48}{}_{}{}^{}\mathrm{Ca}$ nucleus indicates a strong coupling between the ${\mathit{p}}_{3/2}$ neutrons and the core protons.

I propose to use the transverse momentum distribution of lepton pairs in the ${\mathrm{\rho }}^{0\mathrm{-}}$ω peak to measure the QCD transition temperature in ultrarelativistic nuclear collisions. The signal-to-background ratio is approximately unity, and the transition temperature can be determined with roughly 15% accuracy.

The sensitivity of moderate ${\mathit{p}}_{\mathit{T}}$≲8 GeV/c singles inclusive spectra in nuclear collisions to gluon shadowing and jet quenching is estimated using the higing Monte Carlo model. We show how the systematic study of the nuclear dependence of those spectra in p+A can be used to determine the magnitude of gluon shadowing and how the enhanced suppression in A+A would provide information on the energy-loss mechanisms in dense partonic matter.

The influence of trinuclear one-Δ and ΔΔ components on the triton binding energy is studied nonperturbatively using the Hannover and Argonne force models. This is the first such study of ΔΔ effects, and these are found to be appreciable. In the Hannover model, repulsive Δ dispersive effects and attractive Δ three-body-force effects cancel almost exactly, yielding little net Δ effect. A similar result obtains for the Argonne model, yielding a net Δ repulsive effect of only ∼380 keV. Implications for current approaches which make simplifying assumptions about Δ effects are indicated.

The cross section for the ${}_{}{}^8{}_{}{}^{}\mathrm{Li}$(α,n${)}^{11}$B reaction, which is crucial to predictions of primordial nucleosynthesis in inhomogeneous models, has been measured using the radioactive-beam facility of the Institute for Physical and Chemical Research (RIKEN). The reaction cross section to all allowed ${}_{}{}^{11}{}_{}{}^{}\mathrm{B}$ states was found to be larger than that to just the ${}_{}{}^{11}{}_{}{}^{}\mathrm{B}$ ground state by about a factor of 5.

The heaviest known examples of proton radioactivity, ${}_{}{}^{160}{}_{}{}^{}\mathrm{Re}$ and ${}_{}{}^{156}{}_{}{}^{}\mathrm{Ta}$, have been discvovered. Evaporation residues from fusion reactions of 300 MeV ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$ ions with ${}_{}{}^{106}{}_{}{}^{}\mathrm{Cd}$ targets have been mass separated in flight and implanted into a double-sided silicon strip detector. The measured proton energies, total half-lives, and proton branching ratios are 1261±6 keV, 790±160 μs, 91±10%, and 1022±13 keV, ${165}_{\mathrm{-}55}^{+165\mathrm{}}$ ms, ≊100% for ${}_{}{}^{160}{}_{}{}^{}\mathrm{Re}$ and ${}_{}{}^{156}{}_{}{}^{}\mathrm{Ta}$, respectively, indicating that the protons are emitted from a ${\mathit{d}}_{3/2}$ orbital in each case. An energy of 6537±16 keV has been measured for the ${}_{}{}^{160}{}_{}{}^{}\mathrm{Re}$ alpha decay branch.

We study the isospin-dependent component of the effective nucleon-nucleon interaction which causes the ΔT=1 (p,p’) and (p,n) reactions off nuclei. It is shown that, at intermediate energies, the modification to the impulse approximation comes from the g-matrix-type correction and the rearrangement term. They are numerically estimated with the isospin-asymmetric nuclear-matter reaction matrix approach. The isobaric-analog transitions ${}_{}{}^{42}{}_{}{}^{}\mathrm{Ca}$(p,n${)}^{42}$Sc and ${}_{}{}^{48}{}_{}{}^{}\mathrm{Ca}$(p,n${)}^{48}$Sc are analyzed.

We have observed a strong peak in the excitation function for the inelastic scattering reaction ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$${(}^{12}$C${,}^{12}$C($0_2^{+}$)${)}^{12}$C($0_2^{+}$) at an energy of ${\mathit{E}}_{\mathrm{c}.\mathrm{m}.\mathrm{}}$=32.5 MeV. A recoil coincidence arrangement between two double-sided silicon strip detectors was used to detect the α particles from the decaying ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ nuclei, and the reconstructed reaction kinematics were used to calculate the two-body scattering Q value. This excitation-function structure may be interpreted as arising from very highly deformed α-particle chain configurations in the nucleus ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$.

We demonstrate that emission of bosons from a dispersed collection of droplets will produce a two-tiered correlation function reflecting the size of the droplets as well as their spatial distribution. We argue that this two-tiered correlation can signal the existence of a mixed phase of QCD plasma and hadronic gas in relativistic nuclear collisions, and propose that positive kaons will be the best indicators of this structure.

Angular distributions of cross sections and tensor analyzing powers have been measured for ground state transitions in ${}_{}{}^{95}{}_{}{}^{}\mathrm{Mo}$(d,t${)}^{94}$Mo, ${}_{}{}^{119}{}_{}{}^{}\mathrm{Sn}$(d,t${)}^{118}$Sn, and ${}_{}{}^{149}{}_{}{}^{}\mathrm{Sm}$(d,t${)}^{148}$Sm for deuteron energies below the Coulomb barrier. Exact, finite-range distorted-wave Born approximation analyses of these data have been made using both the S- and D-state amplitudes for the three-nucleon systems. A best fit of the data gives ${\mathit{D}}_2$(t)=-0.217±0.010 ${\mathrm{fm}}^2$ and ${\mathrm{\eta }}_{\mathit{t}}$=-0.043±0.002, significantly lower than previous experimental determinations, and in agreement with a recent theoretical prediction of ${\mathrm{\eta }}_{\mathit{t}}$=-0.046±0.001.

Saturation properties of nuclear matter are determined within a Dirac-Brueckner approach. Relativistic covariance is implemented by constructing the complete representation of the nucleon-nucleon amplitude in the Dirac space. As a dynamical model the relativistic one-boson-exchange model is used, including also the negative-energy-state components. A consistent treatment is discussed of nucleon propagation in the nuclear medium. The compressibility obtained for symmetric matter is rather low as compared to other calculations and more in agreement with the value suggested by astrophysical studies.

The interference structure function ${\mathit{f}}_{01}$, the transverse structure function ${\mathit{f}}_{11}$, and the longitudinal structure function ${\mathit{f}}_{00}$ have been determined in a ${}_{}{}^2{}_{}{}^{}\mathrm{H}$(e,e’p) experiment at a four-momentum transfer ${\mathit{Q}}^2$=0.21 (GeV/c${)}^2$. The ${\mathit{f}}_{00}$ and ${\mathit{f}}_{11}$ data are in agreement both with a nonrelativistic calculation that includes the effects of final-state interaction (FSI), meson-exchange currents, and isobar configurations, and with a relativistic calculation that only includes FSI effects. The ${\mathit{f}}_{01}$ data demonstrate the relevance of a relativistic approach even at this low value of the momentum transfer.

We explain why the measured parity-violating asymmetries for ${\mathit{p}}_{1/2}$ compound-nuclear resonances tend to have a common sign. We show that the asymmetry is a sum of two terms: a’ average term dominated by admixtures of distant levels and a term that fluctuates from resonance to resonance dominated by admixtures of nearby compound-nuclear states. The average asymmetry involves single-particle transition amplitudes of the parity-violating interaction, while the fluctuating asymmetry retains a statistical character. Our theoretical estimate of the average asymmetry agrees with a value extracted from experimental data.

The transverse polarization in a plane perpendicular to the nuclear spin has been measured for electrons emitted in the beta decay of polarized ${\mathrm{Li}}^8$ nuclei. The amplitude R of the time-reversal-violating triple correlation between nuclear spin, momentum, and spin of the electron has been determined. Our result, R=0.004±0.014, is consistent with time-reversal invariance and provides a first direct limit on the imaginary charged weak tensor interaction -0.03${\mathrm{C}}_{\mathrm{T}}$+${\mathrm{C}}_{\mathrm{T}}^{\prime }$)/${\mathrm{C}}_{\mathrm{A}}$<0.05.

In superdeformed, heavy nuclei at low spins, M1 transitions enhanced by internal conversion are expected to compete favorably with E2 γ rays. For strongly coupled bands with fairly large B(M1) values, the decay may proceed between the two signature partner bands with very few γ rays emitted. Measured E2 γ ray intensities may imply strict limits on the M1 strength. Experimental evidence for the M1 cross talk dominated by internal conversion is seen in superdeformed bands in ${}_{}{}^{193}{}_{}{}^{}\mathrm{Hg}$.

Strong correlations between baryon stopping in the projectile rapidity hemisphere and target excitation have been found in the light-ion-induced reactions at the BNL Alternating Gradient Synchrotron (AGS) (E814 group). Results in the framework of the relativistic molecular dynamics approach (RQMD) describe recent E814 data quite well. We discuss the RQMD results together with proton and pion data from the E802 group near midrapidity. They have raised the question of whether partial transparency could be seen in these experiments. The RQMD results indicate strong transverse baryon flow in central Si+Au collisions after the projectile has been stopped in the target.

The contribution of virtual pions to the total ${\mathit{K}}^{+}$-nucleus cross section in the ${\mathit{p}}_{\mathit{L}}$=450–1000 MeV/c region is found to be about 10%. With this contribution, the data can be explained without the assumption of nucleons ‘‘swelling’’ in the nucleus.