butenyllithium at 486 µ is 3.0 X 104, calculated using the extrapolated absorbance maxima. This is in good agreement with that obtained for triphenylmeth-yllithium2 (3.3 X 104) in which decomposition is not a problem.

d 2 a/d£l dT for 7r + mesons produced in Tt'p-^ir'ir+n was measured at seven incident energies between 203 and 357 MeV and the integrated reaction cross section was calculated. The matrix element, when extrapolated to threshold and compared with soft-pion calculations, determined the chiral-symmetry-breaking parameter 4 = 0.05 ±0.26, which is consistent with the Weinberg Lagrangian. The large hard-pion contributions at 203 MeV demonstrated the absolute necessity for comparing at threshold.

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The level structure of 3 Ar has been investigated via the stripping reaction Ar(d, p)~A r at an incident deuteron energy of 10.064 MeV with an over-all experimental resolution of approximately 35 keV. Proton groups leading to 44 states of Ar with excitation energies up to 7.727 MeV have been identified. 30 of these states with excitation energies up to 6.488 MeV are neutron-bound.The orbital-angular-momentum-transfer values and the spectroscopic factors have been extracted for 28 of the observed neutron-bound states using zero-range distorted-wave Born-approximation (DWBA) calculations corrected for nonlocality of the optical potential and finite range in the local-energy approximation. One l =0, one l =2, twelve l =3, and fourteen l =1 transfer values are assigned. Spin assignments have been made on the basis of the conventional shell-model ordering of states, by comparison with the level structure of the isotonic nucleus Ca in the reaction Ca(d, p)4 Ca and on the basis of the Lee-Schiffer effect. It is found that the conventional DWBA calculation with spin-orbit coupling reproduces the observed Lee-Schiffer effect for l =1 states remarkably well. The results of the present investigation are in fair agreement with those of recent shell-model calculations.

The deuteron sepctra from {n,d) reactions at 800 MeV near 0' are characterized by a high energy quasielastic scattering peak, and at lower momentum, a quasifree scattering peak. The ratio of the quasifree to quasielastic cross sections is approximately 10:1.Both cross sections exhibit an A '" mass dependence over the range of target nuclei studied. Comparisons are made with corresponding proton-induced quasielastic and quasifree deuteron production.NUCLEAR REACTIONS n+ X-d'. E&~= 800 MeV. Measured deuteron quasiekastic and'quasifree cross sections near 0'.The interaction of high-energy protons with nuclei leads to a copious production of high-energy deuterons at angles near 0, both with and without pion production. ' The deuteron spectra near 0 are characterized by a high-energy peak centered at approximately the momentum expected for free Pd-dP elastic scattering, and a second much more intense peak at about the momentum expected for two-body pN-dm pion production processes. 'These two peaks are respectively attributed to guasielastic (QE) and guasifree (QF) scattering in the target nuclei. The present work is concerned with neutron-induced deuteron production.Most