We calculate the dilepton spectrum arising from hadronic bremsstrahlung and from the radiative decay of the delta in nucleon-nucleon collisions. Comparison is made with the recent p+Be data at 4.9 GeV obtained by the DLS Collaboration at the Bevalac. We argue that dileptons constitute a valuable probe of nuclear dynamics.

Various low-lying energy levels up to 1.145 MeV in ${}_{}{}^{121}{}_{}{}^{}$,123Sb have been Coulomb excited using 3.0–4.0 MeV proton-beam energies. The reduced transition probabilities of the excited levels have been newly deduced from the measured yields of the deexcitation gamma rays. The values of mixing ratios for a few transitions and the removal of ambiguities in the spin values of some levels have been presented from the angular distribution analysis.

In this work we observed a net peak corresponding to the double gamma decay in ${}_{}{}^{90}{}_{}{}^{}\mathrm{Zr}$ without any background subtraction. We set a value of $W_{\gamma \gamma }$/$W_{\mathrm{tot}}$ equal to 2.2(7)×${10}^{\mathrm{-}4}$ assuming the resulting 〈2E1〉/〈2M1〉 ratio of a recent experiment.

Recent measurements of charge symmetry breaking in the np system at 477 MeV, and of $A_{00\mathrm{nn}}$ for np elastic scattering at 220, 325, and 425 MeV also yield accurate analyzing power data. These data allow the energy dependence of the analyzing power zero-crossing angle and the slope of the analyzing power at the zero-crossing angle to be determined. The incident neutron energies span a region where the zero-crossing angle is strongly energy dependent ($E_n$<250 MeV) to where it is almost independent of energy ($E_n$>350 MeV). The results are compared to current phase-shift analysis predictions, recently published data, and the predictions of the Bonn and Paris potentials.

Annihilation of ‘‘heavy’’ antinuclei, such as d¯, t¯, or α¯ in nuclear matter could serve to probe whether the constituent antinucleons annihilate independently of each other or whether a single fireball is formed. In the latter case the total meson multiplicity distribution should have a lower mean and a larger relative width than in the trivial case. The meson spectrum would be correspondingly harder.

All the ${}_{}{}^2{}_{}{}^{}$H(γ,p)n data in the energy range 20–440 MeV have been fitted to a simple phenomenological function. All differential cross-section data were used: The bremsstrahlung data were normalized to the total cross-section values obtained by fitting data provided by monochromatic photon beams. The results obtained give a good representation of the experimental points.

In a previous paper, a quantum-mechanical formulation involving both mean fields and independent-particle fields in many-fermion systems was proposed using the path-integral technique. Then the semiclassical calculation of the energy spectra was performed, and the quantization rule was derived by applying a stationary phase approximation on the path integral. In this paper, a boson-fermion expansion is derived from our formulation using Dirac quantization. As an illustration, the Lipkin model is utilized.

We show that the quasi-two-body absorption process in polarized ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ is sensitive to the short-distance behavior of the T=0 correlation function. The difference between $A_y$ calculated for a free deuteron and a ‘‘deuteron-like’’ pair in ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ exhibits characteristic, energy-dependent signature which should be accessible experimentally.

A recent statistical-model analysis of La Rana et al. has indicated an extremely large deformation in the decay of the compound nucleus ${}_{}{}^{60}{}_{}{}^{}\mathrm{Ni}_{}^{\mathrm{*}}{}_{}{}^{}$, formed in the reaction ${}_{}{}^{30}{}_{}{}^{}\mathrm{Si}$${+}^{30}$Si at $E_{\mathrm{lab}=120\mathrm{}}$ MeV. We believe that their calculations do not support the reported magnitude of reduction in the evaporation Coulomb barrier of the emitting system. By means of a statistical-model calculation, we show that most of the features of their data can be reproduced, assuming spherically symmetric parameters.

In a Comment on our analysis of measured ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ energy spectra for the composite system ${}_{}{}^{60}{}_{}{}^{}\mathrm{Ni}$ ($E^{\mathrm{*}}$=75 MeV and $J_{\max =38\mathrm{}\mathrm{ħ}}$), Nicolis and Sarantites have reported statistical-model calculations which reproduce most of the features of the data assuming spherically symmetric parameters. This result is in disagreement with the strong deformations we have found for this compound nucleus. We show in this reply that the different conclusions concerning the magnitude of reduction in the emission barrier arise essentially from the choice of the transmission coefficients in statistical-model calculations. In particular, optical-model transmission coefficients used by Nicolis and Sarantites provide ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ energy spectra significantly softer than those obtained using transmission coefficients derived from fusion systematics adopted in our calculations. Nevertheless, even using the optical-model transmission coefficients a significant sub-barrier disagreement between data and calculations still exists, indicating important emitter deformations. A comparison between the two sets of proton transmission coefficients reveals strong differences whose influence on ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ energy spectra is discussed.

We analyze the definition of the electromagnetic moments of the ‘‘dressed’’ Δ introduced by Heller, Kumano, Martinez, and Moniz with respect to gauge invariance.

We reply to the preceding Comment.

A search for x rays excited by charged-particle fusion products in a Pt-Pd electrolytic cell with Li-${\mathrm{D}}_2$O electrolyte is reported. Electrolytic loading of the palladium cathode was found to be 0.8 deuterium atoms per Pd atom. No x rays above background were detected and the fusion rate was inferred to be less than 1.6×${10}^{\mathrm{-}20}$ fusions/(sec deuteron).

The alpha-induced fission cross section for ${}_{}{}^{235}{}_{}{}^{}\mathrm{U}$ has been measured for $E_{\alpha }$=3, 4, and 12 MeV for the first time. Taken together with the already published data for protons at extreme sub-barrier energies, these results suggest that the observed cross section below 5 MeV alpha energy may be due to fission of low-lying target states populated by Coulomb excitation. However, it is not clear how such states have the required penetrability of the fission barrier. An explantion of these results may lead to a better understanding of deep sub-barrier tunneling, especially with regard to the fission process.

The s-d-shell effective interaction is derived from the Bonn NN potential, using a G-matrix folded-diagram method. It is found that due to the relatively weak-tensor-force characteristic for the Bonn potential, the effective interaction matrix elements, particularly those with isospin T=0, come out generally more attractive than in previous derivations which were based on conventional local strong-tensor-force NN potentials. This renders the results obtained with the Bonn potential in considerably better agreement with the recent s-d-shell matrix elements of Wildenthal.

The deuteron photodisintegration observables, namely the angular distribution, the total cross section, the ratio (τ) of the photomagnetic and photoelectric components of the total cross section, the ratio of the differential cross section at forward and backward angles to that at 90°, the asymmetry function, and the nucleon polarization near threshold are calculated for several nucleon-nucleon potentials, and their variation with the gamma-ray energy is studied. In the calculations the meson exchange currents and relativistic effects are incorporated. Comparison with the available data is made. It is found that meson exchange currents and relativistic effects manifest themselves more prominently in τ and in nucleon polarization than in other observables.

The polarization transferred to ${}_{}{}^8{}_{}{}^{}\mathrm{Li}$ in the ${}_{}{}^7{}_{}{}^{}\mathrm{Li}$(d→${,}^8$Li→)p reaction was measured for transverse and, for the first time, longitudinal polarized deuteron beams with energies between 1.5 and 10 MeV. Enriched ${}_{}{}^7{}_{}{}^{}\mathrm{Li}$ metallic targets, sufficiently thick to stop the incident beam and all recoils, were used. The longitudinal polarization transfer coefficient is nearly constant over this energy range, with $K_z^z$=0.239±0.005. For deuteron energies above 2.5 MeV, the transverse polarization transfer coefficient is slowly decreasing, with average value $K_y^y$=0.221±0.008. Below 2.5 MeV deuteron energy, $K_y^y$ increases markedly, reaching $K_y^y$=0.31 at $E_d$=1.5 MeV. The polarization relaxation time, $T_1$=(2.87±0.08) s, and the half-life, $t_{1/2}$=(0.838±0.009) s, are in good agreement with prior work.

The preequilibrium hybrid model is extended to account for emission of hard photons using the quasideuteron radiative concept and detailed balance. We analyze proton-nucleus reactions, find good accord with the observed photon spectra at 72 MeV incident proton energy, and predict two times higher spectra than the observed ones at 140 MeV.