Experimental Studies of the Mechanism of Photon Absorption on Light Nuclei
Date
2000Author
Morrow, Steven A
Metadata
Abstract
A measurement of the reaction 12 C (γ,p γ') has been made with tagged
photons in the range 49.47<Eγ <70.24 MeV. The relative population of a triplet of
states, (7/2-,1/2+ ,5/2+ ) at Eex ~7 MeV in the residual nucleus 11B, following the
reaction 12 C (γ,p) has been made by directly resolving their de--excitation γ-ray
decay to the ground state of 11B. This measurement constitutes the highest resolution ever achieved in determining the excitation function of the residual nucleus
after a (γ,p) reaction (~48 keV FWHM at Eex ~7 MeV). Comparison has been
made with the data of Kuzin et al., who also measured the relative populations,
with a resolution of ~270 keV at Eex ~7 MeV. The 7/2-,state at 6.74 MeV has
been observed to be the most strongly excited state of the triplet in agreement
with Kuzin et al. Disagreement has been found for the relative strengths of the
1/2 + and 5/2 + states in the triplet. An estimation of the maximum effect of angular correlations, between the ejected proton and de-excitation γ-ray, has been
included in the analysis. This effect increases the disagreement between the 2
measurements.