Spectral function of p-n pairs in 6Li, from the 6Li(p,p alpha )pn reaction at 200 MeV.

Abstract

The spectral function for {ital p}-{ital n} pairs in the {sup 6}Li ground state (i.e., the distribution in {ital p}-{ital n} relative momentum {h bar}{ital k} for pairs whose c.m. is at rest in the laboratory) was measured for {ital k} ranging from 0.6 to 1.5 fm{sup {minus}1}, using the {sup 6}Li({ital p},{ital p}{alpha}){ital pn} reaction at 200 MeV. These and earlier 120 MeV {sup 6}Li({alpha},2{alpha}){ital pn} measurements show that, when {ital k} increases from 0.1 to 1.5 fm{sup {minus}1}, this function decreases by 4 orders of magnitude and is predicted within a factor of 2 by the plane-wave impulse approximation. The asymmetry for the {sup 6}Li({ital p},{ital p}{alpha}){ital pn} reaction induced with polarized protons was measured at 56{degree} c.m. and found to have the same bombarding-energy dependence as that for {ital p}-{alpha} elastic scattering. The {ital d}-{alpha} cluster probability of {sup 6}Li, determined by the {sup 6}Li({ital p},{ital p}{alpha}){ital d} reaction, was consistent with that found in other intermediate-energy experiments.