C. J. Harvey

Elastic differential cross sections and analyzing powers for p+40,42,44,48Ca at 0.8 GeV☆

Abstract Differential cross sections and analyzing powers for the elastic scattering of 800 MeV polarized protons from 40,42,44,48Ca are reported. A first-order, spin-dependent KMT optical potential analysis is presented from which the rms radii of the neutron densities are deduced. A comparison of these results with other determinations and with various theoretical predictions is given.

Elastic differential cross sections and analyzing powers for p + 54Fe, 58,64Ni at 800 MeV

Abstract Elastic scattering analyzing powers and differential cross sections for 800 MeV → p + 54Fe, 58,64Ni are reported. An approximately mode-independent technique is used to extract information concerning the neutron density distributions of these nuclei.

Observation of isospin mixing in 12C near 19.5 MeV excitation

Abstract A strongly isospin-mixed doublet has been found in 12C near 19.5 MeV excitation energy in a comparison of π− and π+ inelastic scattering at 162 MeV. The π+ and π− comparison technique may be universally employable in self-conjugate nuclei to extract isospin-mixing matrix elements.

Indication of Δ-hole configurations in 12C(15.11 MeV)

Abstract A strong energy dependent enhancement is seen in inelastic pion scattering from 12 C to the 1 + , T = 1 state at 15.11 MeV, but not to the 1 + , T = 0 state at 12.71 MeV. This enhancement may be interpreted as evidence for the direct excitation of delta-hole (Δ-h) components in the wave function of the T = 1 state. The required Δ-h amplitude is estimated and found to be in agreement with calculations of Bohr and Mottelson.

Measurement of isospin mixing between the 1+ doublet in 12C using pion inelastic scattering ☆

Abstract Pion inelastic scattering has been used to extract the off-diagonal charge dependent matrix element, H01, between the Jπ = 1+ doublet of states at 12.71 (T = 0) and 15.11 (T = 1) MeV in 12 C . The reported measurements yield a value, H01 = 148 ±29 keV, in good agreement with recent electromagnetic measurements.

Observation of enhanced excitation of 12C by inelastic pion scattering on the (3,3) pion-nucleon resonance

Abstract Pion inelastic scattering on 12 C to states at an excitation energy of approximately 19 MeV shows a strong enhancement at an incident pion energy near the pion-nucleon (3,3) resonance. This resonance may therefore provide a mechanism for the selective enhancement of inelastic transitions.