The transverse form factor for the 5.37 MeV($2^{+}$,$T=1\mathrm{}$) level of ${}_{}{}^6{}_{}{}^{}\mathrm{Li}$ is analyzed in terms of a phenomenological model to give the configuration amplitudes and transition density. Radiative pion capture rates for the $1s$ atomic orbital of ${}_{}{}^6{}_{}{}^{}\mathrm{Li}$ leading to the two lowest states of ${}_{}{}^6{}_{}{}^{}\mathrm{He}$ are estimated using the phenomenological functions. The radiative pion capture rate to ${}_{}{}^6{}_{}{}^{}\mathrm{He}$(g.s.) agrees with experiment, but the rate to ${}_{}{}^6{}_{}{}^{}\mathrm{He}$($2^{+}$,1.8 MeV) is larger than the measured value. It is shown that if the longitudinal form factor is small at $q\approx m_{\pi }$, the transverse 5.37 MeV form factor gives the radiative pion capture matrix elements directly. As part of this study, the $C2\mathrm{}$ form factor was measured near $q=m_{\pi }$, and its implications on the wave functions are considered.

NUCLEAR REACTIONS ${}_{}{}^6{}_{}{}^{}\mathrm{Li}$($e$,$e^{\prime }$), $E=76-141\mathrm{}$ MeV; $\sigma (E;E_{e^{\prime }},\theta )$. ${}_{}{}^6{}_{}{}^{}\mathrm{Li}$ deduced form factors, wave functions, radiative capture.

The theoretical basis is given for a class of mathematically well defined $\mathrm{NN}\pi$ models. They are designed to describe nucleon-nucleon scattering, pion-nucleon scattering, pion-deuteron scattering, pion production, and absorption. The elementary degrees of freedom of the models are the nucleon, the $\Delta$ isobar, and the pion. The models are relativistic and do not require renormalization.

NUCLEAR SCATTERING Relativistic models, $N-N$ scattering, $\pi -N$ scattering, $\pi -d$ scattering.

Angular distributions of ${}_{}{}^{44}{}_{}{}^{}\mathrm{Sc}_{}^m{}_{}{}^{}$, ${}_{}{}^{46}{}_{}{}^{}\mathrm{Sc}$, ${}_{}{}^{47}{}_{}{}^{}\mathrm{Sc}$, and ${}_{}{}^{48}{}_{}{}^{}\mathrm{Sc}$ emitted in the interaction of ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$ with 0.8, 3.0, 11.5, and 400 GeV protons have been measured. The angular distributions peak at forward angles at 0.8 and 3 GeV but are sideward-peaked at 11.5 and 400 GeV. At 400 GeV, fewer fragments are emitted at forward than at backward angles. Isotopic differences were found to be small. The data were fitted with the function $F_L\left({\theta }_L\right)=1+A_1{cos\theta }_L+A_2{{cos}^2\theta }_L$ and were also analyzed in terms of the two-step model. The values of $A_1$ peak at 3 GeV, go through zero at 11.5 GeV, and become negative at 400 GeV. The values of $A_2$ are zero at 0.8 GeV and become increasingly negative with increasing proton energy. A qualitative explanation in terms of a possible change in the nature of proton-nucleus interactions at high energies is presented.

NUCLEAR REACTIONS ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$($p$,$x$) ${}_{}{}^{44}{}_{}{}^{}\mathrm{Sc}_{}^m{}_{}{}^{}$, ${}_{}{}^{46}{}_{}{}^{}\mathrm{Sc}$, ${}_{}{}^{47}{}_{}{}^{}\mathrm{Sc}$, ${}_{}{}^{48}{}_{}{}^{}\mathrm{Sc}$. $T_p=0.8, 3.0, 11.5, 400$ GeV. Measured angular distributions.

A Wick-formalism treatment of the $\sigma +\omega$ model dynamics is used to obtain the real and imaginary parts of the $\pi$-nucleus optical resulting from the true absorption of "$s$-wave" pions. Good agreement is obtained with the empirical value of the imaginary potential at threshold. The corresponding (dispersive) real potential is attractive. All parameters are taken from other experiments.

NUCLEAR REACTIONS $A({\pi }^{-}, NN)B$; imaginary part of $\pi -A$ optical potential calculated in $\sigma +\omega$ model using Fermi-gas wave functions. Off-shell absorptive amplitude used to calculate corresponding real part from unsubstracted dispersion relation.

Yields of radioactive products from the interactions of stopped ${\pi }^{-}$ with Cu and Ta have been measured. Absolute yields of products ranging down to ${10}^{-5\mathrm{}}$ per stop were determined. The experimental yields are compared with yields calculated with a model that was developed in this work for the stopped-${\pi }^{-}$ interaction. The calculations give excellent agreement with measured total mass yields for Ta, but some discrepancies exist for the independent yields of Hf, Er, and Tm isotopes; in the case of Cu, most independent yields, except for Co and Sc, are in good agreement. Measurements were also made with both stopped ${\pi }^{-}$ and 20-MeV ${\pi }^{+}$ on Cu and Fe to determine the shift in the centroids of the isotopic yields with pion charge.

NUCLEAR REACTIONS Stopped-negative-pion interactions with Cu and Ta. Measured yields of residual radioactive products. Calculated yields from model for the interactions.

Differential cross sections and polarization analyzing powers for proton-deuteron elastic scattering have been measured at 800 MeV incident proton kinetic energy over the range of center-of-mass angles from 14.1° to 153.6°. The differential cross sections are described by the Glauber theory of impulse approximation at forward angles ($-t<\mathrm{}0.5\mathrm{}$) and exhibit the exponential dependence on ${cos\theta }_{\mathrm{c}.\mathrm{m}.\mathrm{}}$ typical for these energies at backward angles (${cos\theta }_{\mathrm{c}.\mathrm{m}.\mathrm{}}<-0.5\mathrm{}$). The analyzing power shows considerable structure with strong positive peaks at forward and backward angles and a sharp dip at $t=-0.4\mathrm{}$ typical at intermediate energies. There is no evidence for correspondence of the angular dependence of the analyzing power with that for the $\mathrm{pp}\to d{\pi }^{+}$ reaction. At large momentum transfer the data favor calculations based on multiple scattering with a modified deuteron form factor rather than $N^{*}$ exchange.

NUCLEAR REACTIONS ${}_{}{}^2{}_{}{}^{}\mathrm{H}$($p$,$p$)${}_{}{}^2{}_{}{}^{}\mathrm{H}$, $E=800\mathrm{}$ MeV, measured $\sigma \left(\theta \right)$ and $A_y\left(\theta \right)$.

We have reexamined the multiple scattering corrections to the reaction ${\pi }^{-}+d\to 2n+\gamma$ in order to extend the validity of previous calculations to a larger neutron-neutron relative momentum interval and to determine the effective range parameter. This extension has been carried out analytically by studying the off-shell properties and energy dependence of the pion-nucleon amplitude. The sensitivity of the photon spectral curves for various approximations is shown, and the importance of the different effects in the values of the neutron-neutron scattering length and effective range is indicated.

NUCLEAR REACTIONS ${\pi }^{-}+d\to 2n+\gamma$, analytical treatment of multiple scattering. Off-shell extension of pion-nucleon amplitude.

Study of the decay of 2.45-min ${}_{}{}^{180}{}_{}{}^{}\mathrm{Re}$ leads to the observation of about 90 $\gamma$ rays and a number of new levels in ${}_{}{}^{180}{}_{}{}^{}\mathrm{W}$. Spins and parties of many of the levels observed are determined using the $log\mathrm{ft}$ values of positron population and/or the $\gamma$-ray depopulation. The allowed unhindered decay from the ${\left(\pi \frac{5}{2^{+}}\right[402\mathrm{}\uparrow ]-\nu \frac{7}{2^{-}}[514\mathrm{}\downarrow \left]\right)}_{1-}$ ${}_{}{}^{180}{}_{}{}^{}\mathrm{Re}$ ground state indicates fragmentation of the ${\left(\pi \frac{5}{2^{+}}\right[402\mathrm{}\uparrow ]-\pi \frac{9}{2^{-}}[514\mathrm{}\uparrow \left]\right)}_{2-}$ configuration among a number of $2^{-}$ states in ${}_{}{}^{180}{}_{}{}^{}\mathrm{W}$. We find tentative observation of the $K=1^{-} \mathrm{and} 0^{-}$ components of the octupole vibration. This would establish the excitation energy of all four expected octupole components in ${}_{}{}^{180}{}_{}{}^{}\mathrm{W}$.

RADIOACTIVITY ${}_{}{}^{180}{}_{}{}^{}\mathrm{Re}$ [from ${}_{}{}^{182}{}_{}{}^{}\mathrm{W}$($p$,$3n$) natural targets]; measured $E_{\gamma }$, $I_{\gamma }$, $\gamma -\gamma$ coinc.; deduced $log\mathrm{ft}$; ${}_{}{}^{108}{}_{}{}^{}\mathrm{W}$ deduced levels $E$, $J$, $\pi$.

The decays of 4.2-min ${}_{}{}^{152}{}_{}{}^{}\mathrm{Tb}$, 3.3-min ${}_{}{}^{154}{}_{}{}^{}\mathrm{Ho}$, 11.8-min ${}_{}{}^{154}{}_{}{}^{}\mathrm{Ho}$, and 82-sec ${}_{}{}^{156}{}_{}{}^{}\mathrm{Tm}$ have been studied by $\gamma$-ray and conversion electron spectroscopy using the He-jet technique. High-spin states in ${}_{}{}^{152}{}_{}{}^{}\mathrm{Gd}$ were also studied in the ${}_{}{}^{152}{}_{}{}^{}\mathrm{Sm}$($\alpha$,$4n\gamma$) reaction at 50 MeV and the ${}_{}{}^{150}{}_{}{}^{}\mathrm{Sm}$($\alpha$,$2n\gamma$) reaction at 28 MeV. The systematic behavior of quasirotational bands in $N=88\mathrm{}$ nuclei has been studied, and observed features in the location of $\beta$- and $\gamma$-band states are shown to be explainable from a consideration of available orbitals in a Nilsson diagram. Microscopic calculations employing fourth and sixth order versions of the boson expansion model of Tamura, Kishimoto, and Weeks reproduce the known low-lying positive parity states in ${}_{}{}^{150}{}_{}{}^{}\mathrm{Sm}$, ${}_{}{}^{152}{}_{}{}^{}\mathrm{Gd}$, ${}_{}{}^{154}{}_{}{}^{}\mathrm{Dy}$, and ${}_{}{}^{156}{}_{}{}^{}\mathrm{Er}$. Experimentally observed negative-parity states are explained remarkably well by a quadrupole-octupole coupling model, but a backbending plot suggests a possible change in intrinsic structure above spin 11.

RADIOACTIVITY ${}_{}{}^{152}{}_{}{}^{}\mathrm{Tb}_{}^m{}_{}{}^{}$, ${}_{}{}^{154}{}_{}{}^{}\mathrm{Ho}_{}^{m_1}{}_{}{}^{}$, ${}_{}{}^{154}{}_{}{}^{}\mathrm{Ho}_{}^{m_2}{}_{}{}^{}$, ${}_{}{}^{156}{}_{}{}^{}\mathrm{Tm}$; $I_{\gamma }$, $E_{\gamma }$, $I_{\mathrm{ce}}$, $E_{\mathrm{ce}}$, $\gamma -\gamma$ coin. ${}_{}{}^{152}{}_{}{}^{}\mathrm{Gd}$, ${}_{}{}^{154}{}_{}{}^{}\mathrm{Dy}$, ${}_{}{}^{156}{}_{}{}^{}\mathrm{Er}$ deduced levels, ICC, $J$, $\pi$; systematics, comparison with microscopic theory.

NUCLEAR REACTIONS ${}_{}{}^{152}{}_{}{}^{}\mathrm{Sm}$($\alpha$,$4n$), $E_{\alpha }=50\mathrm{}$ MeV; ${}_{}{}^{150}{}_{}{}^{}\mathrm{Sm}$($\alpha$,$2n$), $E_{\alpha }=28\mathrm{}$ MeV; measured $E_{\gamma }$, $I_{\gamma }$, $I_{\gamma }\left(\theta \right)$, $I_{\mathrm{ce}}$, $\gamma -\gamma$ coin. ${}_{}{}^{152}{}_{}{}^{}\mathrm{Gd}$ deduced levels, ICC, $J$, $\pi$. Enriched targets, Ge(Li), Si(Li) detectors.

The $g$ factors of the first excited and 1.094 MeV states of ${}_{}{}^{168}{}_{}{}^{}\mathrm{Er}$ have been obtained by the time integral and time differential perturbed angular correlation methods using two large volume Ge(Li) detectors. The results are found to be $g(2+)=0.31\mathrm{}\pm 0.03$ for the first excited state and $g(4-)=0.24\mathrm{}\pm 0.01$ for the 1.094 MeV state. These values are compared to the experimental results reported previously and to theoretical predictions.

RADIOACTIVITY ${}_{}{}^{168}{}_{}{}^{}\mathrm{Er}$ level; measured $\gamma \gamma$ coin., $\gamma \gamma (\theta ,t)$, deduced $T_{\frac{1}{2}}$, relaxation constants; measured $\gamma \gamma (\theta ,H)$, $\gamma \gamma (\theta ,H,t)$. TIPAC, TDPAC methods, deduced $g$.

The magnetic hyperfine splitting constant $\frac{g{\mu }_N{H}_{\mathrm{HF}}}{h}$ of ${}_{}{}^{97}{}_{}{}^{}\mathrm{Ru}$ as a dilute impurity in Fe has been determined by the technique of nuclear magnetic resonance on oriented nuclei to be 117.69±0.02 MHz. With the known hyperfine field for $\mathrm{Ru}\mathrm{Fe}$ of -504±12 kG the ground-state nuclear $g$ factor of ${}_{}{}^{97}{}_{}{}^{}\mathrm{Ru}$ is deduced to be (-)0.306±0.008. The resonance shift and the spin-lattice-relaxation time have been measured as functions of an external magnetic field.

RADIOACTIVITY ${}_{}{}^{97}{}_{}{}^{}\mathrm{Ru}$ from ${}_{}{}^{96}{}_{}{}^{}\mathrm{Ru}$($n$,$\gamma$); NMR on oriented nuclei. Deduced $\mu$, Knight shift, relaxation times.

We have investigated the decay of ${}_{}{}^{85}{}_{}{}^{}\mathrm{Kr}_{}^m{}_{}{}^{}$, ${}_{}{}^{85}{}_{}{}^{}\mathrm{Kr}_{}^g{}_{}{}^{}$, ${}_{}{}^{85}{}_{}{}^{}\mathrm{Sr}_{}^m{}_{}{}^{}$, and ${}_{}{}^{85}{}_{}{}^{}\mathrm{Sr}_{}^g{}_{}{}^{}$ using Ge(Li) spectroscopy and intrinsic Ge Compton-suppression spectroscopy techniques. We observe levels at ($J^{\pi }$ in parentheses) g.s. ($\frac{5}{2^{-}}$), 151.18 ($\frac{3}{2^{-}}$), 281.01 ($\frac{1}{2^{-}}$), 513.998 ($\frac{9}{2^{+}}$), 731.79 ($\frac{3}{2^{-}}$), 868.05 ($\frac{7}{2^{-}}$), and 921 ($\frac{1}{2^{-}}$,$\frac{3}{2^{-}}$) KeV. Our data suggest that the ∼880 keV level observed in ($t$,$\alpha$) and (${}_{}{}^3{}_{}{}^{}\mathrm{He}$,$d$) reactions is the known 868-keV level. The $Q_{\mathrm{EC}}$ value for the ${}_{}{}^{85}{}_{}{}^{}\mathrm{Sr}_{}^m{}_{}{}^{}$ decay is calculated to be 1323±20 keV from our $\frac{\mathrm{EC}}{{\beta }^{+}}$ intensity data. We use the cluster-vibration model to calculate the ${}_{}{}^{85}{}_{}{}^{}\mathrm{Rb}$ level structure and electromagnetic decay properties. For the latter, we discuss the role of the $M1\mathrm{}$ tensor operator.

NUCLEAR STRUCTURE Cluster-vibration model, influence of $M1\mathrm{}$ tensor term.

RADIOACTIVITY ${}_{}{}^{85}{}_{}{}^{}\mathrm{Kr}$, ${}_{}{}^{85}{}_{}{}^{}\mathrm{Kr}_{}^m{}_{}{}^{}$, ${}_{}{}^{85}{}_{}{}^{}\mathrm{Sr}$, and ${}_{}{}^{85}{}_{}{}^{}\mathrm{Sr}_{}^m{}_{}{}^{}$. Measured $E_{\beta }$,$I_{\beta }$. ${}_{}{}^{85}{}_{}{}^{}\mathrm{Rb}$ deduced levels, $E_{\beta }$, $I_{\beta }$, $J$,$\pi$. Ge(Li) detector, Compton-suppression spectrometer.

Theoretical $E4\mathrm{}$ transition matrix elements calculated in the full $d_{\frac{5}{2}}-s_{\frac{1}{2}}-d_{\frac{3}{2}}$ shell-model space are presented for excitations of some ground states of stable nuclei for $18\le A\le 38$. These matrix elements have been used to calculate inelastic transition probabilities for electromagnetic and hadronic probes. Available data on the relative magnitudes and energy distributions of $E4\mathrm{}$ excitation strengths are found to be well reproduced theoretically thereby. Based on several experimentally measured transition strengths, the empirical isoscalar $E4\mathrm{}$ effective charge is found to be $e_p+e_n=(2.0\mathrm{}\pm 0.2)e$. This is similar in magnitude to the analogous isoscalar $E2\mathrm{}$ effective charge, but is much larger than existing theoretical estimates.

NUCLEAR STRUCTURE ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$, ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}$, ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$, ${}_{}{}^{22}{}_{}{}^{}\mathrm{Ne}$, ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$, ${}_{}{}^{25}{}_{}{}^{}\mathrm{Mg}$, ${}_{}{}^{26}{}_{}{}^{}\mathrm{Mg}$, ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$, ${}_{}{}^{30}{}_{}{}^{}\mathrm{Si}$, ${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$, ${}_{}{}^{34}{}_{}{}^{}\mathrm{S}$, ${}_{}{}^{36}{}_{}{}^{}\mathrm{Ar}$, ${}_{}{}^{38}{}_{}{}^{}\mathrm{Ar}$; calculations for the strengths of $E4\mathrm{}$ inelastic scattering transitions and their proton and neutron components; complete $0d_{\frac{5}{2}}-1\mathrm{}{s}_{\frac{5}{2}}-0\mathrm{}{d}_{\frac{3}{2}}$ shell-model wave functions; Chung-Wildenthal Hamiltonians.

The complex single-particle field in nuclear matter is computed in the framework of Brueckner's theory, in the case of the realistic nucleon-nucleon interaction of Hammann and Ho-Kim. The Hartree-Fock, the core polarization, and the correlation contributions are calculated; renormalization corrections are also evaluated. The results are compared with those derived from a dispersion relation approach. Particular attention is paid to the behavior of the effective mass near the Fermi surface, where it presents a narrow enhancement. Following a recent suggestion by Orland and Schaeffer, the nuclear matter results are adapted to finite nuclei by assuming that the relevant variable is the difference between the single-particle energy and the Fermi energy. This yields fair agreement between the strength functions for quasihole states calculated here and those measured from ($e$,$e^{\prime }p$) knockout processes.

NUCLEAR STRUCTURE Potential energy and width of single-particle states from Hammann-Ho-Kim interaction.

The leading-order correlation corrections to the independent particle shell model momentum density distribution for ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ are calculated using the Brueckner theory of finite nuclei. The Pauli corrected defect functions are calculated using Reid soft core B and de Tourreil-Sprung interaction potentials with harmonic oscillator starting wave functions and experimental shell model starting energies. The short-range correlations are found to modify significantly the independent particle shell model momentum density distribution for low momenta and to dominate it for high momenta. Comments are made concerning the selection of ground state nuclear wave functions for calculating quasielastic scattering processes.

NUCLEAR STRUCTURE ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$, calculated momentum density distribution. Brueckner method finite nuclei; Reid soft core, Sprang potentials used.

A clear understanding of how to construct the boson expansion of a collective fermion pair operator is given. The criteria for the applicability of the procedure are also discussed. Following this prescription, the Pauli-principle violation is made negligible for the low-lving states of collective nuclei.

NUCLEAR STRUCTURE Boson expansion; criteria for truncation and convergence; collective motions.

Analytic expressions for obtaining first four moments of noninteracting as well as interacting bosons have been given in terms of matrix elements. These expressions have been utilized to obtain general conditions under which the eigenvalue distributions for bosons tend towards the Gaussian distribution. Results for pairing and $Q·Q$ operators in an $s-d$ boson shell have also been given.

NUCLEAR STRUCTURE Analytic expressions, first four moments, noninteracting and interacting bosons, eigenvalue distribution, conditions leading to Gaussian distribution, pairing and $Q-Q$ operators, $s-d$ boson space.

The nucleon-nucleon interaction, originating from the phenomenological quark-quark interaction: one gluon exchange with an ad hoc confining potential, is rigorously derived. The coupling constants of this potential and the quark masses—which determine the strengths of the $\mathrm{NN}$ potentials in the various channels—had been previously reliably determined from the masses of the $s$-wave baryons. Two distinguishing features of this study are the reliable nature of the coupling constants and quark masses used and the inclusion of the detailed radial dynamics of quarks. The main results are as follows: (i) exchange of colored quarks among other things leads to short-range strongly repulsive central $\mathrm{NN}$ potentials in the odd channels alone, i.e., it yields the saturation property of nuclear forces; (ii) the spin-orbit (tensor) potential between quarks goes over to the spin-orbit (tensor) potential between nucleons; (iii) both these spin-orbit and tensor potentials between nucleons are found to have the correct signatures but they are very weak; (iv) there is insufficient attraction in the $\mathrm{NN}$ potentials in the intermediate range, so that the colored quark-exchange mechanism is not adequate to keep the deuteron bound. The $\mathrm{NN}$ potentials derived from one gluon exchange with an ad hoc confining potential are compared finally with the corresponding phenomenological ones.

NUCLEAR STRUCTURE $\mathrm{NN}$ interaction from nonrelativistic quantum chromodynamics. Quark exchange, spin-orbit and tensor potentials, short-range repulsive core.

Recent measurements of the ($\overrightarrow{p}$,$t$) reaction on targets in the mass range $106\le A\le 128$ have shown a change in the sign of the analyzing power at forward angles for transitions to the lowest $2^{+}$ states. The ($\overrightarrow{t}$,$p$) reaction has been used in a similar search for corresponding effects on targets of ${}_{}{}^{96}{}_{}{}^{}\mathrm{Mo}$, ${}_{}{}^{106}{}_{}{}^{}\mathrm{Pd}$, and ${}_{}{}^{126}{}_{}{}^{}\mathrm{Te}$. In contrast to the ($\overrightarrow{p}$,$t$) results, the analyzing power for $L=2\mathrm{}$ transitions in the ($\overrightarrow{t}$,$p$) measurements does not show a sign change and the data are fitted with standard distorted-wave Born approximation calculations.

NUCLEAR REACTIONS ${}_{}{}^{96}{}_{}{}^{}\mathrm{Mo}$, ${}_{}{}^{106}{}_{}{}^{}\mathrm{Pd}$, ${}_{}{}^{126}{}_{}{}^{}\mathrm{Te}$ ($\overrightarrow{t}$,$p$) measured $\sigma \left(\theta \right)$ $A_y$ DWBA analysis.

The analyzing power of the ${}_{}{}^{109}{}_{}{}^{}\mathrm{Ag}$($\overrightarrow{p}$,$p_0$) reaction has been measured in the sub-Coulomb region. The volume integral of the imaginary potential deduced from this measurement has a much larger value than for Zr and Sn, confirming the value $W_D=20\mathrm{}$ MeV obtained in an ${}_{}{}^{109}{}_{}{}^{}\mathrm{Ag}$($p$,$n$) investigation by Johnson et al. The large volume integral is probably an indication of shell effects in the optical model. The volume integral does not determine the absorption cross section uniquely.

NUCLEAR REACTIONS ${}_{}{}^{109}{}_{}{}^{}\mathrm{Ag}$($\overrightarrow{p}$,$p_0$), $E=6.06\mathrm{}$ MeV; measured $A\left(\theta \right)$; deduced optical-model parameters; enriched target $\theta =30-160\mathrm{}$°; $\Delta \theta =5\mathrm{}$°.