Inelastic scattering of 800 Me Y protons has been studied for targets of~Pb, '~Sm, and " Sn. At excitation energies above particle emission threshold a spectrum of giant resonances is clearly in evidence. Angular distributions~ere extracted for the high-lying peaks (-20 MeV excitation energy) in Pb and ' Sm. Collective model distorted-wave Born approximation analyses of these data show that isoscalar octupole and dipole states dominate the spectra.

Understanding the receptivity of hypersonic flows to free-stream disturbances is crucial for predicting laminar to turbulent boundary layer transition. Input-output analysis as a receptivity tool considers which free-stream disturbances lead to the largest response from the boundary layer using the global linear dynamics. Two technical challenges are addressed. First, we extend recent work by Kamal et al. [1] and restrict the allowable forcing to physically realizable inputs via a free-stream boundary modification to the classic input-output formulation. Second, we develop a hierarchical input-output (H-IO) analysis which allows us to solve the three-dimensional problem at a fraction of the computational cost otherwise associated with directly inverting the fully three-dimensional resolvent operator. Next, we consider Mach 5.8 flows over a sharp cone and blunt cone with a 3.6 mm spherically blunt tip. H-IO correctly predicts that the sharp cone boundary layer is most receptive to slow acoustic waves at an optimal incidence angle of 10 • , validating the method. We then investigate the effect of free-stream disturbances on the blunt cone boundary layer, and identify two distinct vorticity-dominated receptivity mechanisms for the oblique first mode instability at 10 kHz and an entropy layer instability at 75 kHz. Our results reveal these receptivity processes to be highly three-dimensional in nature, involving both the nose-tip and excitation along narrow bands at certain azimuthal angles along the oblique shock downstream. We interpret these processes in terms of critical angles from linear shock/perturbation interaction theory.

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Proton cross sections forPb have been measured for elastic and inelastic scattering to the 12+, 6.10 MeV, 12&, 6.43 MeV, 122, 7.06 MeV, and 14, 6.74 MeV states at Ep =318 MeV. We analyze the inelastic transitions in the distorted wave impulse approximation and use the previously published electron scattering results to constrain the wave functions in the unnatural parity calculations. A 13 state is discussed as an unresolved "contaminant" to the 12~, 6.43 MeV state. Mixing between the 12 neutron and proton particle-hole configurations is found to reduce substantially the differences reported previously in observed proton and electron quenching factors. This results in greater quenching for the 12&, 7.06 MeV state, and less quenching for the 12&, 6.43 MeV state than was previously reported in (e, e') analyses.

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