Spin-flip probability angular distributions for proton scattering from the $2_1^{+}$ level of ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$ have been determined between 25° and 165° (in steps of 10°) at 15 incident energies between 14.5 and 35.5 MeV and, to obtain a more detailed energy dependence at backward angles, spin-flip probabilites have also been measured between 115° and 165° at ten additional energies. In order to extend the study of spin-flip probabilities also to other nuclei and to complement previous angular distributions, further backward angle data have been taken at 13 energies for ${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$ and near 40 MeV for ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ and ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$. The experimental results have been compared with coupled-channel calculations based on the rotational model and, for ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$, also with the predictions of microscopic antisymmetrized distorted wave calculations including two-step contributions. The collective analysis proves that spin-flip probabilities are particularly sensitive to the sign of the quadrupole deformation.

NUCLEAR REACTIONS ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$($p$,$p^{\prime }\gamma$), $E_p=14.5-41.1\mathrm{}$ MeV; ${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$($p$,$p^{\prime }\gamma$), $E_p=15.5-40.9\mathrm{}$ MeV; ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$($p$,$p^{\prime }\gamma$), $E_p=41.1\mathrm{}$ Mev; ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$($p$,$p^{\prime }\gamma$), $E_p=35.3, 40.9$ MeV; measured $\sigma (E_p,{\theta }_{p^{\prime }},{\phi }_{\gamma }=90\mathrm{}°)$ for the $2_1^{+}$ level; microscopic CC analysis; deduced sign of quadrupole deformation parameters; microscopic ADWBA analysis including two-step GR contributions for ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$. ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$ enriched target. ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$, ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$, and ${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$ natural targets.

The resonating group method is a successful method for treating nuclear many-body problems in an approximate way. Although the method uses the basic nucleon-nucleon interactions and treats the antisymmetrization of identical particles in an exact way, correction terms cannot be introduced without employing an overcomplete set of basis states for the wave function and the associated theoretical and numerical problems. We present an alternative derivation of the resonating group method, which incorporates bound state approximation for the resolvent operator corresponding to the two-body fragmentation channel appearing in an antisymmetrized version of the $N$-body Lippmann-Schwinger equation for the wave functions. Similar considerations when applied to the transition matrix Lippmann-Schwinger equation yield the transition matrix version of the resonating group method. Such derivation of the resonating group method allows us to introduce correction terms in a controlled way. The antisymmetrized $N$-body Lippmann-Schwinger equation for the transition matrix connecting specific two-body channels is reduced to a two-body Lippman-Schwinger equation with an optical potential and a multiple scattering series for the optical potential, which unlike the usual multiple scattering series is expected to converge at low energy. The lowest order approximation to the optical potential is the resonating group method interaction. We show how to introduce corrections to the optical potential due to excited discrete and certain continuous spectrum of the relevant resolvent operator. The present scheme is also applicable for the calculation of nuclear bound states.

NUCLEAR REACTIONS Improvement on the resonating group method, optical potential, multiple scattering series for the optical potential, bound state approximation, nuclear structure.

Certain versions of distorted and reduced scattering equations are found to admit continuum spurious solutions apart from the commonly known discrete spurious solutions. The spurious threshold corresponding to continuum spurious solutions may occur at an energy lower than the physical bound state energy and this may make the use of such equations questionable both for bound state and scattering problems. The spurious threshold, however, disappears in approximate calculations using the bound state approximation. The origin of these spuriosities lies in a different type of factorization than that found by Newton in the context of the formulation of Weinberg and may shed light on the spurious spectrum of other formulations.

NUCLEAR REACTIONS Scattering theory, discrete and continuum spurious spectrum, distorted and reduced scattering equations, bound state approximation.

Multistep contributions to elastic and inelastic scattering of intermediate energy hadrons from collective nuclei are treated analytically to all orders. Exploiting the eikonal formalism and nuclear geometry, we obtain closed form expressions for the relevant amplitudes without the need for coupled channels. Agreement with experiment, where available, is excellent, and interesting predictions are made for large momentum transfer experiments and "poor" energy resolution.

NUCLEAR REACTIONS Analytical expressions for hadron-nucleus coupled channels calculations. ${}_{}{}^{166}{}_{}{}^{}\mathrm{Er}$, ${}_{}{}^{182}{}_{}{}^{}\mathrm{W}$, ${}_{}{}^{154}{}_{}{}^{}\mathrm{Sm}$ ($p$,$p^{\prime }$), calculated $\sigma \left(\theta \right)$ exclusive to $0^{+}$, $2^{+}$, $4^{+}$, and inclusive.

A time-dependent multichannel nonrelativistic quantum scattering theory is established for systems which contain identical particles. The symmetry properties of the theory are rooted in the abstract algebraic relationships between permutations. The formalism of second quantization is thus avoided. Appropriate wave and scattering operators are defined, including those for systems with long range (e.g., Coulomb) interactions. A correctly symmetrized dynamical equation for the symmetric form of the transition operator is derived and used to develop an optical potential formalism.

NUCLEAR REACTIONS Nonrelativistic multichannel scattering theory for identical particles, wave and scattering operators, dynamical equations, optical potentials.

Levels in ${}_{}{}^{102}{}_{}{}^{}\mathrm{Tc}$ up to an excitation energy of 1 MeV were studied by means of the ${}_{}{}^{100}{}_{}{}^{}\mathrm{Mo}$(${}_{}{}^3{}_{}{}^{}\mathrm{He}$,$p$)${}_{}{}^{102}{}_{}{}^{}\mathrm{Tc}$ and ${}_{}{}^{104}{}_{}{}^{}\mathrm{Ru}$($d$,$\alpha$)${}_{}{}^{102}{}_{}{}^{}\mathrm{Tc}$ reactions at incident energies of 25 and 20 MeV, respectively. Tentative spin assignments were deduced from distorted-wave Born approximation analyses of the proton angular distributions. The results are discussed in the framework of the shell model.

NUCLEAR REACTIONS ${}_{}{}^{100}{}_{}{}^{}\mathrm{Mo}$(${}_{}{}^3{}_{}{}^{}\mathrm{He}$,$p$), $E_{{}_{}{}^3{}_{}{}^{}\mathrm{He}}=25\mathrm{}$ MeV; measured $\sigma (E_p,\theta )$, $\theta =5\mathrm{}°-40\mathrm{}°$. ${}_{}{}^{104}{}_{}{}^{}\mathrm{Ru}$($d$,$\alpha$), $E_d=20\mathrm{}$ MeV; measured $E_{\alpha }$ at $\theta =15\mathrm{}°$. Enriched targets. Split-pole spectrograph. ${}_{}{}^{102}{}_{}{}^{}\mathrm{Tc}$ deduced levels, tentative $L_{\mathrm{np}}$,$J^{\pi }$. DWBA analysis. Calculated: $\pi 1g_{\frac{9}{2}}\nu 1g_{\frac{7}{2}}$ proton-neutron multiplet structure.

The level structure and the decay properties of levels in ${}_{}{}^{63}{}_{}{}^{}\mathrm{Zn}$ up to 2750 keV excitation have been studied through the ${}_{}{}^{63}{}_{}{}^{}\mathrm{Cu}$($p$,$n\gamma$) reaction at incident proton energy between 5 and 7.8 MeV. Singles $\gamma$-ray spectra at angles of observation ${\theta }_{\gamma }=0\mathrm{}°, 20°,40°,55°,70°,\mathrm{and}90°$ and $\gamma \gamma$-coincidence spectra were obtained with high resolution Ge(Li) detectors. From these experiments a decay scheme of ${}_{}{}^{63}{}_{}{}^{}\mathrm{Zn}$ has been obtained which includes 33 levels. The lifetimes or limits on the lifetimes of 24 levels were determined through the Doppler shift attenuation method by studying the systematic energy shift of $\gamma$-ray peaks in the angular distribution data. The analysis of angular distributions yielded multipole mixing ratios and $J^{\pi }$ values for several states. The experimental information, wherever complete, was employed to calculate reduced transition probabilities.

NUCLEAR REACTIONS ${}_{}{}^{63}{}_{}{}^{}\mathrm{Cu}\mathrm{}(p,n)\mathrm{}{}_{}{}^{63}{}_{}{}^{}\mathrm{Zn}_{}^{*}{}_{}{}^{}\left(\gamma \right)$, $E=5.0-7.8\mathrm{}$ MeV; measured $E_{\gamma }$, $I_{\gamma }\left(\theta \right)$, $\Delta E_{\gamma }\left(\theta \right)$, $\gamma \gamma$ coincidences; deduced ${}_{}{}^{63}{}_{}{}^{}\mathrm{Zn}$ levels, $J$, $\pi$, branching ratios, $\tau$, $\delta$, $B\left(\Lambda \right)$ values; enriched target, Ge(Li) detector.

A microscopic calculation of the second-order imaginary optical potential for ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$($\alpha$,$\alpha$) is made for incident energies of 31 and 100 MeV using random phase approximation transition densities for intermediate excited states. The projectile is treated as an elementary particle, and the alpha-nucleon interaction is normalized by fitting $3^{-}$ inelastic cross sections with a folded M3Y potential. The use of an optical Green's function for the intermediate propagator is found to be important. Equivalent local potentials are obtained and used to calculate elastic scattering cross sections. Agreement with low-angle experimental data is fair at 31 MeV but at 100 MeV the calculated cross sections indicate much too little absorption.

NUCLEAR REACTIONS ($\alpha$,$\alpha$) scattering, calculation of imaginary optical potential at $E=31\mathrm{} \mathrm{and} 100$ MeV.

Elastic and inelastic proton differential cross sections have been measured for ${}_{}{}^{232}{}_{}{}^{}\mathrm{Th}$ and ${}_{}{}^{239}{}_{}{}^{}\mathrm{U}$ at incident energies of 20 and 26 MeV. Scattered protons were detected with a split-pole spectrometer using a position sensitive delay-line proportional counter. Proton groups up to the $8^{+}$ level in the ground state rotational band have been measured. The analysis of the data has been done using coupled-channel calculations for deformed nuclei. We have studied the sensitivity of the calculations to (a) the optical model parameters, (b) the shape of the nuclear charge distribution, (c) the coupling scheme assumed among the levels, and (d) the magnitude and sign ($\pm {\beta }_6$) of the deformation parameters. The calculated multipole potential moments, obtained from the best fits to the data, agree well with the values deduced from proton measurements at other energies. They are also in good agreement with the values reported from Coulomb excitation and inelastic scattering using $\alpha$ particles and neutron probes.

NUCLEAR REACTIONS ${}_{}{}^{232}{}_{}{}^{}\mathrm{Th}$, ${}_{}{}^{238}{}_{}{}^{}\mathrm{U} \mathrm{}(p,p)\mathrm{} \left(p{p}^{\prime }\right)$, $E=26\mathrm{}$ MeV; calculated $\sigma \left(\theta \right)$; deduced deformation parameters and multipole moments of the potential. Coupled channel analysis.

Cross sections were measured for ($n$,$t$) reactions on ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}$, ${}_{}{}^{59}{}_{}{}^{}\mathrm{Co}$, and ${}_{}{}^{93}{}_{}{}^{}\mathrm{Nb}$ over the incident neutron energy region of 16 to 20 MeV using activation and tritium counting. Three or four segments of the material under investigation were so arranged that a compact hemispherical geometry was obtained. The incident neutrons were produced by the ${}_{}{}^3{}_{}{}^{}\mathrm{H}$($d$,$n$)${}_{}{}^4{}_{}{}^{}\mathrm{He}$ reaction and the neutron energy spectrum effective for each segment was determined via Monte Carlo calculations. After irradiation, the accumulated tritium was separated from each segment by vacuum extraction and its activity determined by lowlevel anticoincidence ${\beta }^{-}$ counting in the gas phase. The ($n$,$t$) cross section increases with the incident neutron energy. The excitation function of the ($n$,$t$) reaction on ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}$ is described well by Hauser-Feshbach calculations; in the case of ${}_{}{}^{59}{}_{}{}^{}\mathrm{Co}$ and ${}_{}{}^{93}{}_{}{}^{}\mathrm{Nb}$, however, the calculated cross section values are appreciably smaller than the experimental data, suggesting that for those nuclei the contributions of statistical processes are rather small.

NUCLEAR REACTIONS ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}$, ${}_{}{}^{59}{}_{}{}^{}\mathrm{Co}$, ${}_{}{}^{93}{}_{}{}^{}\mathrm{Nb}$ ($n$,$t$); $E_n=16-20\mathrm{}$ MeV; measured $\sigma$; Hauser-Feshbach analysis.

One measure of the age of the galaxy is derived from the Re-Os decay chronometer. The ${}_{}{}^{186,187}{}_{}{}^{}\mathrm{Os}$ capture cross sections are crucially important in the use of this chronometer. In this paper we describe a small revision of our measurements and point out the high degree of consistency of the measured cross sections with the revised results from other laboratories. Using a standard model of nucleosynthesis and these cross sections, the duration of $r$-process nucleosynthesis is estimated to be (8.9±2.0)×${10}^9$ yr, the age of the galaxy to be ≈ 13.5×${10}^9$ yr, and the universe to be ≈ 14.5×${10}^9$ yr.

NUCLEAR REACTIONS Maxwellian average capture cross sections, $E=2.5-450\mathrm{}$ keV, ${}_{}{}^{187}{}_{}{}^{}\mathrm{Os}$($n$,$n^{\prime }$), $E=30\mathrm{}$ keV; nucleosynthesis, $r$ process, age of galaxy, age of universe.

We propose a new technique allowing the decomposition of the light- and heavy-ion elastic scattering amplitude into its barrier and internal wave components as defined by Brink and Takigawa. The method requires only minimum programming as it makes use of the reflection coefficients generated by any optical model code. Also, it can be applied to a wide range of potentials including folding model and model-independent potentials. The use and physical interest of the method are illustrated by applying it to a few representative examples ranging from $\alpha$ to heavy-ion scattering.

NUCLEAR REACTIONS Calculation of barrier and internal wave components of elastic scattering amplitude; application to light- and heavy-ion scattering.

${}_{}{}^{84}{}_{}{}^{}\mathrm{Sr}$ has been investigated by means of conventional in-beam gamma-ray spectroscopy with the reactions ${}_{}{}^{76}{}_{}{}^{}\mathrm{Ge}$(${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$,$4n$) and ${}_{}{}^{81}{}_{}{}^{}\mathrm{Br}$(${}_{}{}^6{}_{}{}^{}\mathrm{Li}$,$3n$). Lifetimes of 10 levels have been measured by the recoil distance Doppler shift technique. Four positive and at least two negative parity bands have been found. The energies of the ground state band and quasigamma band as well as the $E2\mathrm{}$ transition strengths are compared with theoretical values obtained from the proton-neutron interacting boson model. A relatively long lived $8^{+}$ state has been found, to which we assign the ${\left(\nu g_{\frac{9}{2}}\right)}^{-2\mathrm{}}$ configuration.

NUCLEAR REACTIONS ${}_{}{}^{76}{}_{}{}^{}\mathrm{Ge}$(${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$,$4n\gamma$), $E=48-60\mathrm{}$ MeV; ${}_{}{}^{81}{}_{}{}^{}\mathrm{Br}$(${}_{}{}^6{}_{}{}^{}\mathrm{Li}$,$3n\gamma$), $E=19-32\mathrm{}$ MeV, measured $E_{\gamma }$, $I_{\gamma }$, $\gamma \gamma$ coincidence, $\gamma$ angular distribution, recoil distance Doppler shift; ${}_{}{}^{84}{}_{}{}^{}\mathrm{Sr}$ deduced levels, $J$, $\pi$, $\tau$. Enriched targets, Ge(Li) detectors.

An effective nucleon-nucleon spin-orbit force is included in a single-channel resonating-group calculation for the ${}_{}{}^3{}_{}{}^{}\mathrm{He}$(${}_{}{}^3{}_{}{}^{}\mathrm{H}$)+$\alpha$ system up to a c.m. energy of 113.1 MeV. The parameters of the spin-orbit force were chosen to reproduce the phase shifts for $p+\alpha$ scattering at low energies and the bound-state properties of ${}_{}{}^7{}_{}{}^{}\mathrm{Li}$ and ${}_{}{}^7{}_{}{}^{}\mathrm{Be}$. A phenomenological, parity-dependent imaginary potential is used to account for reaction channels. The calculation gives a reasonable account of the experimental differential cross sections and analyzing powers available in this energy region.

NUCLEAR REACTIONS ${}_{}{}^3{}_{}{}^{}\mathrm{He}$(${}_{}{}^3{}_{}{}^{}\mathrm{H}$)+$\alpha$, bound states to 113.1 MeV (c.m.); calculated elastic differential cross sections and analyzing powers; resonating-group method.

A variation on the inward-outward method of solving coupled Schrödinger equations is presented, which facilitates calculations for reactions induced by massive heavy ions in which many channels are open. Application is made to the 340 MeV ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ar}$ + ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$ reaction and a new physical phenomenon is predicted: nuclear deexcitation to the elastic channel.

NUCLEAR REACTIONS Method of calculating with coupled channels model. Calculated ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$ (${}_{}{}^{40}{}_{}{}^{}\mathrm{Ar}$, ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ar}$′) ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$ ($0^{+}$,...${12}^{+}$).

Thick-target recoil properties of seven fragments ranging from ${}_{}{}^{24}{}_{}{}^{}\mathrm{Na}$ to ${}_{}{}^{52}{}_{}{}^{}\mathrm{Mn}$ produced in the interaction of 18.5 GeV ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ ions and 400 GeV protons with Cu, Ag, Gd, Ta, Au, and U have been measured. After correction for the difference in bombarding energy, the results were used to test the factorization hypothesis. While the properties associated with the ablation step (range, kinetic energy) obey the hypothesis, those associated with abrasion ($\frac{F}{B}$,${\beta }_{\parallel }$) do not, there being an ∼30% enhancement in these values in reactions induced by ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ ions. The scaling power of various energy related variables is examined and the systematics of the recoil parameters are developed. The implications of these results for the reaction mechanism are considered.

NUCLEAR REACTIONS Cu, Ag, Gd, Ta, Au, U [${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ and $p$, fragments ($A=24-52\mathrm{}$)] $T_{{}_{}{}^{12}{}_{}{}^{}\mathrm{C}}=18.5\mathrm{}$ GeV, $Tp=400\mathrm{}$ GeV. Measured mean range and forward-to-backward ratio. Natural targets, Ge(Li) detectors. Deduced mean kinematic properties.

The system ${}_{}{}^{165}{}_{}{}^{}\mathrm{Ho}$ + ${}_{}{}^{56}{}_{}{}^{}\mathrm{Fe}$ was studied at a bombarding energy of $E_{\mathrm{lab}}=462\mathrm{}$ MeV. The experimental $Z$ distributions measured as a function of angle and energy are discussed. The integrated fragment $Z$ distribution of the light reaction fragment is fairly broad and centered close to the charge of the projectile. The kinetic energy distribution extends from the quasielastic region down to energies smaller than the Coulomb energy of touching spherical nuclei. The angular distribution is peaked forward of the quarter-point angle and rises at small angles, which is interpreted as due to orbiting. Correlations of observed fragment $Z$ distributions with energy loss give an indication of the progress of the reaction. Charge distributions show an average drift towards larger asymmetry and an increase in width with increasing energy damping. Results are presented taking account of the Coulomb barrier for two choices of the scission radius. With the aid of a phenomenological description, the initial angular momenta $l_i$ and interaction times are deduced. Interaction times are compared to other characteristic times for the reaction as a function of $l$. Results from a classical dynamical model using a proximity formalism and one-body transport are shown for comparison to experimental observables and deduced quantities. The influence of a neck degree of freedom on the calculated trajectories is studied in some detail.

NUCLEAR REACTIONS ${}_{}{}^{165}{}_{}{}^{}\mathrm{Ho}$(${}_{}{}^{56}{}_{}{}^{}\mathrm{Fe}$,$x$), $E_{\mathrm{lab}}=462\mathrm{}$ MeV; measured $\sigma (\theta ,E,Z)$; damped reaction; fusion-fusion; deduced angular momenta, interaction times; comparison to dynamical calculations.

One criticism of the thermodynamic model for deuteron production has been that it may not be possible for deuterons to exist inside the fireball. We give arguments why deuterons can exist inside the fireball, although they cannot exist in cold nuclear matter at normal density. We redefine the Berkeley coalescence model and show that with this redefinition, the coalescence model is rather close to the thermodynamic prescription. We show that this redefined coalescence model is equivalent to the quantum mechanical sudden approximation model considered by Kapusta. We construct the grand canonical partition function for interacting fermions up to the second virial coefficient and show that the redefined coalescence model and the simple thermodynamic model are two limits of a more complete theory.

NUCLEAR REACTIONS Deuteron production; relativistic heavy ions; thermodynamic model; coalescence model; sudden approximation model; second virial coefficient.

We have measured cross sections for the production of isotopes of Bk through No in bombardments of ${}_{}{}^{248}{}_{}{}^{}\mathrm{Cm}$ with ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$, ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$, ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$, and ${}_{}{}^{22}{}_{}{}^{}\mathrm{Ne}$ ions at energies near the Coulomb barrier. In general, the peak of the mass-yield curve for each element is about two mass units larger for ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$ and ${}_{}{}^{22}{}_{}{}^{}\mathrm{Ne}$ than for ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ and ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$, reflecting the neutron excess of the projectiles. The production cross sections and maxima of the actinide isotopic distributions are at least as favorable for production of neutron-rich actinides as those measured for irradiation of ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$ and ${}_{}{}^{248}{}_{}{}^{}\mathrm{Cm}$ with very heavy ions. The observation of so many neutron-rich products between the masses of the target and compound nucleus suggests a direct transfer reaction in which the product nuclide is formed with relatively low excitation which minimizes depletion from prompt fission.

NUCLEAR REACTIONS ${}_{}{}^{248}{}_{}{}^{}\mathrm{Cm}$(${}_{}{}^{16,18}{}_{}{}^{}\mathrm{O}$,$X$), (${}_{}{}^{20,22}{}_{}{}^{}\mathrm{Ne}$,$X$) $E\left({}_{}{}^{16,18}{}_{}{}^{}\mathrm{O}\right)=98, 97$ MeV, $E({}_{}{}^{20,22}{}_{}{}^{}\mathrm{Ne}=115, 116 \mathrm{MeV})$; measured $\sigma$ and isotopic distributions for $Z=97-102\mathrm{}$.

The magnetic moments of the $2_1^{+}$ states in ${}_{}{}^{186,188}{}_{}{}^{}\mathrm{Os}$ and ${}_{}{}^{194,196}{}_{}{}^{}\mathrm{Pt}$ isotopes have been measured by the transient field technique at ion recoil velocities $1.6\lesssim \frac{v}{v_0}\lesssim 2.8$. The transient field was assumed to follow the parametrization proposed by Shu et al. for ions in the range $8<Z<\mathrm{}62\mathrm{}$. The $g$ factors obtained for osmium isotopes $g\left({}_{}{}^{186}{}_{}{}^{}\mathrm{Os}\right)=0.262\mathrm{}\left(15\right)\mathrm{}$ and $g\left({}_{}{}^{188}{}_{}{}^{}\mathrm{Os}\right)=0.300\mathrm{}\left(15\right)\mathrm{}$ are in excellent agreement with independent Mössbauer and external field measurements, indicating that the adopted parametrization is valid up to $Z=76\mathrm{}$. However, the same analysis yields $g$ factors for the platinum isotopes which are smaller than previously reported: $g\left({}_{}{}^{194}{}_{}{}^{}\mathrm{Pt}\right)=0.203\mathrm{}\left(6\right)\mathrm{}$ and $g\left({}_{}{}^{196}{}_{}{}^{}\mathrm{Pt}\right)=0.213\mathrm{}\left(21\right)\mathrm{}$.

NUCLEAR REACTIONS ${}_{}{}^{186,188}{}_{}{}^{}\mathrm{Os}$(${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$, ${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$′)${}_{}{}^{186,188}{}_{}{}^{}\mathrm{Os}$($2_1^{+}$), ${}_{}{}^{194,196}{}_{}{}^{}\mathrm{Pt}$(${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$, ${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$′)${}_{}{}^{194,196}{}_{}{}^{}\mathrm{Pt}$($2_1^{+}$); $E_s\sim 80$ MeV; enriched targets; measured $W(\theta ,B,\infty )$ through polarized iron; deduced $g\left(2_1^{+}\right)$.