Resonant neutron absorption spectroscopy has been used to determine the temperature dependence of the average kinetic energy <£) of the Cu in Bi2Sr2CaCu2C>8 for the directions along and perpendicular to the c axis. (E) is directly related to the Cu phonon density of states and shows essentially normal behavior as a function of temperature for the c-axis direction. However, a sudden drop in (E) is observed at the superconducting transition for the motions in the Cu-O planes.

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Tripleaxis spectrometry has been used to determine the magnetic excitations in YBa2Cu307. Polarized measurements at 100 K show the scattering consists of a peak near 40

Using 14-Mev deuterons from the M.I.T. cyclotron, proton spectra have been measured for many heavy and medium atomic weight elements. The range of the protons was measured in aluminum foils by the method of "peaking" with a triple proportional counter. From the Q-value of the ground-state proton group (measured relative to a Q-value of 5.50 Mev for the aluminum ground-state group), the neutron binding energy of the residual nucleus has been obtained. These values are compared to the maximum gamma-ray energy obtained from thermal neutron capture, A few neutron binding energies have been measured from the (d } t) reaction and are compared with values obtained from the (7, n) threshold. Several neutron binding energies have been computed from radioactive decay energies and measured neutron binding energies. All neutron binding energies have been compared with the values predicted from the semi-empirical mass formula. A sharp drop in neutron binding energy of about 2.2 Mev occurs at the completion of the closed shell of 126 neutrons. A drop, a little greater than 2 Mev, occurs at 50 neutrons. There is also a decrease in the region of 82 neutrons. There also seems to be a decrease of about 1 Mev in the region of 29 neutrons, but this is not very conclusive.The differential cross section of the ground-state peaks from even Z, odd A isotopes at forward angles are much smaller (about a factor of ten) than the differential cross sections of the groundstate peaks from the same Z but even A isotopes. The groundstate peaks from Sn 117 and Pb 207 , however, are about 50 percent that of the even A isotopes.

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