Wk. Wilson et al., RELATIVE DIELECTRON YIELDS IN P-4.9 GEV(P AND P+D INTERACTIONS FROM E(BEAM) = 1.0), Physics letters. Section B, 316(2-3), 1993, pp. 245-249
The beam energy and invariant mass dependence of the dielectron yield
in p + d interactions relative to the yield in p + p interactions is p
resented for incident kinetic energies from 1.0-4.9 GeV. The ratio of
the yield in p + d interactions to that in p + p interactions decrease
s from 10.5 +/- 1.6 at 1.0 GeV to 1.96 +/- 0.08 at 4.9 GeV for electro
n pairs with invariant masses greater-than-or-equal-to 0.15 GeV/c2. Th
e large ratio at 1.0 GeV suggests that dielectron production in the p
+ d system is dominated by a p + n process. The beam energy dependence
of the ratio indicates that this p + n contribution decreases with re
spect to the other dielectron sources as the incident energy is increa
sed.