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Angular distributions for the inelastic scattering of 13.0 MeV deuterons on 104;106;108;110Pd were measured with the Sao Paulo Pelletron-Enge-Spectrograph facility in the range of 12(0) < thetalab < 64(0). A Coulomb-Nuclear Interference analysis, employing the Distorted Wave Born Approximation with the Deformed Optical Model as transition potential, under well established global optical parameters, was applied to the first quadrupolar excitations. The values of C = / , the ratio of charge to isoscalar deformation lengths, and of ()² were extracted through the comparison of experimental and predicted cross section angular distributions. The ratios of reduced charge to isoscalar transition probabilities, B(EL) to B(ISL) respectively, are related to the square of the parameter C and were thus obtained with the advantage of scale uncertainties cancellation. For 104Pd, and preliminary for 108Pd, the respective values of C = 1.18(3) and C = 1.13(4) reveal an enhanced contribution of the protons relative to the neutrons to the excitation, while a smaller effect is found for 106Pd, C = 1.06(3) and for 110Pd, C = 1.07(3), in comparison with the value C = 1.00 expected for homogenous collective excitations.

Taking {sup 94}Mo(d,d{sup {prime}}){sup 94}Mo(2{sub 1}{sup +}) at 13.2 MeV incident energy as an example, a discussion is made about the influence of known experimental uncertainties in the primary data on the precision of the B(E2) and B(IS2) values, extracted in Coulomb-nuclear interference (CNI) measurements in a correlated way. The reflexes of judicious variations of three optical model parameters (around the global prescription) on the extracted values are also examined. The good quality of the data obtained with the S. Paulo Pelletron-Enge-Spectrograph facility is shown to allow for a 2{endash}3{percent} statistical uncertainty level for these quantities, within a distorted-wave Born approximation-deformed optical model approach. The accuracy of relative values of the ratio B(E2)/B(IS2), which may be linked to the ratio of proton to neutron quadrupole moments, is argued to be of similar order. {copyright} {ital 1997} {ital The American Physical Society}

Coulomb-nuclear interference data for incident energies between 9 and 17 MeV were obtained in the form of elastic and inelastic (to the ${2}_{1}^{+}$ states) excitation functions of backscattered (\ensuremath{\theta}\ensuremath{\simeq}172.8\ifmmode^\circ\else\textdegree\fi{}) alpha particles on $^{100,102,104}\mathrm{Ru}$. The analysis was done in a distorted-wave Born approximation within a deformed optical model approach. B(E2) values, obtained from the charge deformation lengths ${\mathrm{\ensuremath{\delta}}}^{\mathit{C}}$ extracted from the low energy data, are compatible for the three isotopes within \ensuremath{\sim} 2\ensuremath{\sigma} with published values. The nuclear quadrupolar deformation lengths ${\mathrm{\ensuremath{\delta}}}^{\mathit{N}}$, obtained from the analysis of the interference region of the excitation functions, and also of one angular distribution at 22 MeV measured for $^{100}\mathrm{Ru}$ are generally lower than the corresponding charge deformation lengths, the difference increasing with increasing A of the isotope, ${\mathrm{\ensuremath{\delta}}}^{\mathit{N}}$ being 18% lower than ${\mathrm{\ensuremath{\delta}}}^{\mathit{C}}$ for $^{104}\mathrm{Ru}$ (${2}_{1}^{+}$). Nuclear deformation lengths associated with the ${3}_{1}^{\mathrm{\ensuremath{-}}}$ states of $^{100,102,104}\mathrm{Ru}$ and with the ${4}_{2}^{+}$ state of $^{100}\mathrm{Ru}$ at 2.367 MeV were also obtained as a by-product of the present work. \textcopyright{} 1996 The American Physical Society.

Angular distribution for the inelastic scattering of 28 MeV 6Li on 76Ge was measured using the Sao Paulo PelletronEngeSplit-pole Spectrograph facility. The coulomb-nuclear interference (CNI) analysis was applied to the first quadrupole state transition. The values of CL = δCL/δNL, the ratio of charge to isoscalardeformation lengths, and of (δNL02 were extracted through the comparison of experimental and DWBA-DOMP predicted cross section. The ratio of reduced charge to isoscalartransition probabilities, B(EL) to B(ISL) respectively, are related to the square of the parameter CL and were thus obtained with the advantage of scale uncertainties cancellation. The value of C2 = 1.10(2) obtained indicate a slight predominance of the protons relative to the neutrons for 76Ge.

Ratios of $B(E2)$ to $B(IS2)$, that is, of the reduced quadrupole transition probabilities related, respectively, to charge and mass were extracted through Coulomb-nuclear interference (CNI) for the excitation of the ${2}_{1}^{+}$ states in $^{70,72,74}\mathrm{Ge}$, with a relative accuracy of less than 4%. For this purpose, the CNI angular distributions associated with the inelastic scattering of 28-MeV incident $^{6}\mathrm{Li}$ ions accelerated by the S\~ao Paulo Pelletron, and momentum analyzed by the Enge magnetic spectrograph were interpreted within the DWBA-DOMP approach (distorted wave approximation for the scattering process and deformed optical model for the structure representation) with global $^{6}\mathrm{Li}$ optical parameters. The present CNI results demonstrate an abrupt change in the $B(E2)/B(IS2)$ ratio for $^{74}\mathrm{Ge}$: although for $^{70,72}\mathrm{Ge}$, values of the order of 1.0 or slightly higher were obtained, this ratio is 0.66 (7) for $^{74}\mathrm{Ge}$. The heavier Ge isotope is thus one of the few nuclei that, so far, have been shown to present clear mixed symmetry components in their ground-state band.

The /sup 91/Zr(d,d')/sup 91/Zr( reaction has been investigated at 17 MeV incident energy. Up to 4.8 MeV excitation, 73 levels, some of them new, were identified. Angular distributions associated to approx.40 levels were attributed to pure L = 2, 3, or 5 excitations, concentrated in energy regions where the /sup 90/Zr core exhibits 2/sup +/, 3/sup -/, and 5/sup -/ states. The partial deformation parameters ..beta../sub L//sup prime/ obtained show agreement with those from low energy proton scattering for L = 2, but there is a systematic difference for L = 3 and L = 5, which is discussed. Attention is drawn to the high excitation probability of the first excited state of /sup 91/Zr, as measured by the ..beta../sub 2/approx. =0.18 value obtained, a factor of approx.2 above all other values for nuclei with A = 90 +- 2.

Attention is drawn to the strong collective {ital L}=4 direct excitation of the state at 2.367 MeV in {sup 100}Ru by inelastic scattering of 16 MeV protons characterized by a deformation parameter {beta}{sub 4}=0.10, one of the highest reported for any region of the mass table.