We study the effect of bound nucleon form factors on charged-current neutrino-nucleus scattering. The bound nucleon form factors of the vector and axial-vector currents are calculated in the quark-meson coupling model. We compute the inclusive ${}^{12}\mathrm{C}\left({\nu }_{\mu },{\mu }^{-}\right)X$ cross sections using a relativistic Fermi gas model with the calculated bound nucleon form factors. The effect of the bound nucleon form factors for this reaction is a reduction of $\sim 8\%$ for the total cross section, relative to that calculated with the free nucleon form factors.

${}^4\mathrm{He}$ possesses a second $0^{+}$ state; the transition form factor has been measured via inelastic electron scattering. The nature of the $0_2^{+}$ state’s spatial structure has been controversial. An accurate four-nucleon calculation utilizing a realistic $NN$ force (Argonne $\mathrm{V}{8}^{\prime }$) plus phenomenological $NNN$ three-body force has been performed for both the ${}^4\mathrm{He}$ ground state and second $0^{+}$ state $(E_x=20.21\mathrm{MeV})$ using the Gaussian expansion method. The calculated one-body densities and transition density show a significant difference between the states. The resulting impulse approximation transition form factor ${}^4\mathrm{He}(e,e^{\prime }){}^4\mathrm{He}\left(0_2^{+}\right)$ agrees with the available data. The overlap of the $0_2^{+}$ wave function with the trinucleon ground state suggests that the structure is primarily a loosely bound $3N+N$ system and not a breathing mode. It is found that a major part of the energy-weighted $E0$ sum rule value is exhausted by nonresonant, low-energy continuum states other than the second $0^{+}$ state, in contrast to heavier nuclei where a dominant fraction of the sum-rule limit is exhausted by the second $0^{+}$ state because it corresponds to a collective, breathing mode.

The $\beta$ decay of ${}^{11}\mathrm{Li}$ has been investigated at TRIUMF-ISAC using a high-efficiency array of Compton suppressed $\mathrm{HPGe}$ detectors. From a line-shape analysis of the Doppler-broadened peaks observed in the ${}^{10}\mathrm{Be}$ $\gamma$ spectrum, both the half-lives of states in ${}^{10}\mathrm{Be}$ and the energies of the $\beta$-delayed neutrons feeding those states were obtained. Furthermore, it was possible to determine the excitation energies of the parent states in ${}^{11}\mathrm{B}\mathrm{e}$ with uncertainties comparable to those obtained from neutron spectroscopy experiments. These data suggest that the $\beta$ decay to the $8.81\mathrm{MeV}$ state in ${}^{11}\mathrm{Be}$ occurs in the ${}^9\mathrm{Li}$ core and that one neutron comprising the halo of ${}^{11}\mathrm{Li}$ survives in a halolike configuration after the $\beta$-delayed neutron emission from this level.

Alpha particles emitted from an excited projectilelike fragment $\left({\mathrm{PLF}}^{*}\right)$ formed in a peripheral collision of two intermediate-energy heavy ions exhibit a strong preference for emission towards the targetlike fragment. The interplay of the initial deformation of the ${\mathrm{PLF}}^{*}$ caused by the reaction, Coulomb proximity, and the rotation of the ${\mathrm{PLF}}^{*}$ results in the observed anisotropic angular distribution. Changes in the shape of the angular distribution with excitation energy are interpreted as being the result of forming more elongated initial geometries in the more peripheral collisions.

In this paper we show that a system of three fermions is exactly solvable for the case of a single-$j$ in the presence of an angular momentum-$J$ pairing interaction. On the basis of the solutions for this system, we obtain new sum rules for six-$j$ symbols. When the Hamiltonian contains only an interaction between pairs of fermions coupled to spin $J=J_{\max }=2j-1$, the “non-integer” eigenvalues of three fermions with angular momentum $I$ around the maximum appear as “non-integer” eigenvalues of four fermions if $I$ is around (or larger than) $J_{\max }$. This pattern is also found in five and six fermion systems. A boson system with spin $l$ exhibits a similar pattern.

We analyze the spin-orbit coupling term in the nuclear energy density functional in terms of a zero-range NN-contact interaction and finite-range contributions from two-pion exchange. We show that the strength of the spin-orbit contact interaction as extracted from high-precision nucleon-nucleon potentials is in perfect agreement with that of phenomenological Skyrme forces employed in non-relativistic nuclear structure calculations. Additional long-range contributions from chiral two-pion exchange turn out to be relatively small. These explicitly density-dependent contributions reduce the ratio of the isovector to the isoscalar spin-orbit strength significantly below the Skyrme value $1∕3$. We perform a similar analysis for the strength function of the ${(\mathbf{\nabla }\rho )}^2$-term and find values not far from those of phenomenological Skyrme parametrizations.

Single-particle resonant states in spherical nuclei are studied by an analytic continuation in the coupling constant (ACCC) method within the framework of the self-consistent relativistic mean field (RMF) theory. Taking the neutron resonant state $\nu 1g_{9∕2}$ in ${}^{60}\mathrm{Ca}$ as an example, we examine the analyticity of the eigenvalue and eigenfunction for the Dirac equation with respect to the coupling constant by means of a Padé approximant of the second kind. The RMF-ACCC approach is then applied to ${}^{122}\mathrm{Zr}$ and, for the first time, this approach is employed to investigate both the energies, widths, and wave functions for $l\ne 0$ resonant states close to the continuum threshold. Predictions are also compared with corresponding results obtained from the scattering phase shift method.

Differential cross sections for the process ${\pi }^{-}p\to \gamma n$ have been measured at Brookhaven National Laboratory’s Alternating Gradient Synchrotron with the Crystal Ball multiphoton spectrometer. Measurements were made at 18 pion momenta from 238 to $748\mathrm{MeV}∕c$, corresponding to $E_{\gamma }$ for the inverse reaction from 285 to $769\mathrm{MeV}$. The data have been used to evaluate the $\gamma n$ multipoles in the vicinity of the $N\left(1440\right)$ resonance. We compare our data and multipoles to previous determinations.

The physics program in Hall A at Jefferson Lab commenced in the summer of 1997 with a detailed investigation of the ${}^{16}\mathrm{O}(e,e^{\prime }p)$ reaction in quasielastic, constant $(q,\omega )$ kinematics at $Q^2\approx 0.8{(\mathrm{GeV}∕c)}^2$, $q\approx 1\mathrm{GeV}∕c$, and $\omega \approx 445\mathrm{MeV}$. Use of a self-calibrating, self-normalizing, thin-film waterfall target enabled a systematically rigorous measurement. Five-fold differential cross-section data for the removal of protons from the $1p$-shell have been obtained for $0<p_{\mathrm{miss}}<350\mathrm{MeV}∕c$. Six-fold differential cross-section data for $0<E_{\mathrm{miss}}<120\mathrm{MeV}$ were obtained for $0<p_{\mathrm{miss}}<340\mathrm{MeV}∕c$. These results have been used to extract the $A_{LT}$ asymmetry and the $R_L$, $R_T$, $R_{LT}$, and $R_{L+TT}$ effective response functions over a large range of $E_{\mathrm{miss}}$ and $p_{\mathrm{miss}}$. Detailed comparisons of the $1p$-shell data with Relativistic Distorted-Wave Impulse Approximation (RDWIA), Relativistic Optical-Model Eikonal Approximation (ROMEA), and Relativistic Multiple-Scattering Glauber Approximation (RMSGA) calculations indicate that two-body currents stemming from meson-exchange currents (MEC) and isobar currents (IC) are not needed to explain the data at this $Q^2$. Further, dynamical relativistic effects are strongly indicated by the observed structure in $A_{LT}$ at $p_{\mathrm{miss}}\approx 300\mathrm{MeV}∕c$. For $25<E_{\mathrm{miss}}<50\mathrm{MeV}$ and $p_{\mathrm{miss}}\approx 50\mathrm{MeV}∕c$, proton knockout from the $1s_{1∕2}$-state dominates, and ROMEA calculations do an excellent job of explaining the data. However, as $p_{\mathrm{miss}}$ increases, the single-particle behavior of the reaction is increasingly hidden by more complicated processes, and for $280<p_{\mathrm{miss}}<340\mathrm{MeV}∕c$, ROMEA calculations together with two-body currents stemming from MEC and IC account for the shape and transverse nature of the data, but only about half the magnitude of the measured cross section. For $50<E_{\mathrm{miss}}<120\mathrm{MeV}$ and $145<p_{\mathrm{miss}}<340\mathrm{MeV}∕c$, $(e,e^{\prime }pN)$ calculations which include the contributions of central and tensor correlations (two-nucleon correlations) together with MEC and IC (two-nucleon currents) account for only about half of the measured cross section. The kinematic consistency of the $1p$-shell normalization factors extracted from these data with respect to all available ${}^{16}\mathrm{O}(e,e^{\prime }p)$ data is also examined in detail. Finally, the $Q^2$-dependence of the normalization factors is discussed.

Electroproduction of the $\omega$ meson was investigated in the ${}^{1}H\left(e,e^{\prime }p\right)\omega$ reaction. The measurement was performed at a four-momentum transfer $Q^2\approx 0.5{\mathrm{GeV}}^2$. Angular distributions of the virtual photon-proton center-of-momentum cross sections have been extracted over the full angular range. These distributions exhibit a strong enhancement over $t$-channel parity exchange processes in the backward direction. According to a newly developed electroproduction model, this enhancement provides significant evidence of resonance formation in the $\gamma *p\to \omega p$ reaction channel.

Proton production in the intermediate $p_T$ region in $d+\mathrm{Au}$ collisions is studied in the parton recombination model. The recombination of soft and shower partons is shown to be important in central collisions, but negligible in peripheral collisions. It is found that the large nuclear modification factor for proton production can be well reproduced by a calculation of the $3\text{−}\text{quark}$ recombination process.

The ${}^{66}\mathrm{Ge}$ and ${}^{68}\mathrm{Ge}$ nuclei are studied by means of the shell model with the extended $P+QQ$ Hamiltonian, which succeeds in reproducing experimentally observed energy levels, moments of inertia, and other properties. The investigation using the reliable wave functions predicts $T=0$,$J=9$ one-proton–one-neutron $\left(1p1n\right)$ alignment in the $g_{9∕2}$ orbit, at high spins (${14}_1^{+}$, ${16}_1^{+}$, and ${18}_1^{+}$) in these $N\approx Z$ even-even nuclei. It is shown that a series of the even-$J$ positive-parity yrast states (observed up to ${26}_1^{+}$ for ${}^{68}\mathrm{Ge}$) consists of the ground-state band and successive three bands with different types of particle alignments (two-neutron, $1p1n$, two-proton–two-neutron) in the $g_{9∕2}$ orbit.

Reaction $K^{-}p\to {\pi }^0{\pi }^0{\Sigma }^0$ was measured with the Crystal Ball multiphoton spectrometer at eight $K^{-}$ momenta from 514 to $750\mathrm{MeV}∕c$. Dynamics and the energy dependence of the reaction are shown by Dalitz plots, invariant mass spectra, production angular distributions, and total cross sections. The dipion invariant-mass spectra for $K^{-}p\to {\pi }^0{\pi }^0{\Sigma }^0$ show an enhancement in the low mass region; the opposite is the case for the $K^{-}p\to {\pi }^0{\pi }^0\Lambda$ and ${\pi }^{-}p\to {\pi }^0{\pi }^{0}n$ reactions. There is no direct evidence for a $f_0\left(600\right)$-meson contribution to ${\pi }^0{\pi }^0$ production. Everywhere ${\sigma }_t(K^{-}p\to {\pi }^0{\pi }^0{\Sigma }^0)⪡{\sigma }_t(K^{-}p\to {\pi }^0{\pi }^0\Lambda )$.

Quark model intrinsic wave functions of highly energetic pions in the reaction $\overline{p}p\to {\pi }^{-}{\pi }^{+}$ are subjected to a relativistic treatment. The annihilation is described in a constituent quark model with $A2$ and $R2$ flavor-flux topology, and the annihilated quark-antiquark pairs are in ${}^{3}P_0$ and ${}^{3}S_1$ states. We study the effects of pure Lorentz transformations on the antiquark and quark spatial wave functions and their respective spinors in the pion. The modified quark geometry of the pion has considerable impact on the angular dependence of the annihilation mechanisms.

We present a fit to the low energy antiproton ring at CERN data on $\overline{p}p\to {\pi }^{-}{\pi }^{+}$ differential cross sections and analyzing powers motivated by relativistic considerations. Within a quark model describing this annihilation, we argue, since the pions are highly energetic, that relativistic effects cannot be neglected. The intrinsic pion wave functions are Lorentz transformed to the center-of-mass frame. This change in quark geometry gives rise to additional angular dependence in the transition operators and results in a relative enhancement of higher $J⩾2$ partial wave amplitudes. The fit to the data is improved significantly.

The $g$ factors and quadrupole moments of the $21∕2^{-}$ and $33∕2^{+}$ isomers in ${}^{193}\mathrm{Pb}$ have been measured by the time-differential perturbed $\gamma$-ray angular distribution method as $g(21∕2^{-})=-0.059\left(11\right)$, $\mid Q(21∕2^{-})\mid =0.22\left(2\right)e\mathrm{b}$ and $g(33∕2^{+})=-0.171\left(9\right)$, $\mid Q(33∕2^{+})\mid =0.45\left(4\right)e\mathrm{b}$. The results support the three-neutron configurations ${\left(1i_{13∕2}\right)}_{{12}^{+}}^2\otimes 3p_{3∕2}$ and ${\left(1i_{13∕2}\right)}^3$ for the $21∕2^{-}$ and $33∕2^{+}$ states, respectively. The quadrupole moment of the ${12}^{+}$ isomer in ${}^{194}\mathrm{Pb}$ described by the two-neutron ${\left(1i_{13∕2}\right)}^2$ configuration has been remeasured as $\mid Q\left({12}^{+}\right)\mid =0.48\left(3\right)e\mathrm{b}$ in perfect agreement with the previous data. The experimental results are discussed within a microscopic Bardeen-Cooper-Schrieffer approach in a number-projected one- and three-quasiparticle neutron space, and in the frame of the pairing plus quadrupole tilted-axis cranking model.

The quasifree ${\Delta }^{++}$ production mechanism in charge exchange reactions on the ${}^{12}\mathrm{C}$ nucleus has been studied here in the framework of the DWIA. In this study, the ${\Delta }^{++}$ is assumed to be produced in a one-step process through the elementary $pp\to n{\Delta }^{++}$ reaction. Since the charge exchange reaction on a nucleus is localized in the low density region, the Lagrangian for describing the $\Delta$ excitation in the nucleus is taken from the study of the free $pp\to n{\Delta }^{++}$ reaction. The present calculation explores the $\Delta$ mass in the nucleus phenomenologically, so that the calculated results could reproduce both the ${\pi }^{+}p$ invariant mass distribution and the ejectile energy distribution spectra.

Suppression of high $p_T$ hadron spectra in high-energy heavy-ion collisions at different energies is studied within a perturbative QCD parton model incorporating medium-induced parton energy loss. The $p_T$ dependence of the nuclear modification factor $R_{AA}\left(p_T\right)$ is found to depend on both the energy dependence of the parton energy loss and the power-law behavior of the initial jet spectra. The high $p_T$ hadron suppression at $\sqrt{s}=62.4\mathrm{GeV}$ and its centrality dependence are studied in detail. The overall values of the modification factor are found to provide strong constraints on the lifetime of the dense matter.

Experimental data of complex cluster radioactivity $\left({}^{14}\mathrm{C}\text{–}{}^{34}\mathrm{Si}\right)$ are systematically analyzed and investigated with different models. The half-lives of cluster radioactivity are well reproduced by a new formula between half-lives and decay energies and by a microscopic density-dependent cluster model with the renormalized M3Y nucleon-nucleon interaction. The formula can be considered as a natural extension of both the Geiger-Nuttall law and the Viola-Seaborg formula from simple $\alpha$ decay to complex cluster radioactivity where different kinds of clusters are emitted. It is useful for experimentalists to analyze the data of cluster radioactivity. A new linear relationship between the decay energy of cluster radioactivity and the number of $\alpha$ particles in the cluster is found where the increase of decay energy for an extra $\alpha$ particle is between 15 and 17 MeV. The possible physics behind this new linear relationship is discussed.

Recent experiments show that there may exist proton halos in exotic light proton-rich nuclei. We investigate the effect of an extended proton density distribution on the cross sections and form factors of elastic electron scattering from the exotic proton drip-line nuclei ${}^{28}\mathrm{S}$ and ${}^{12}\mathrm{O}$. With charge density distributions from the self-consistent relativistic mean field model, we calculate the cross sections and form factors for elastic electron scattering in the eikonal approximation. The numerical results are compared with the available data of the stable nuclei ${}^{32}\mathrm{S}$ and ${}^{16}\mathrm{O}$. The results show that the form factors and cross sections for elastic electron scattering at intermediate-momentum transfers are very sensitive to the alterations of the charge density distributions of the last protons in exotic nuclei ${}^{28}\mathrm{S}$ and ${}^{12}\mathrm{O}$. This is an interesting combination of the reliable relativistic mean field model with the model of electron-nucleus scattering and it can be useful for future experiments.