Measurement of Double Parton Scattering in p¯p Collisions at s} = 1.8 TeV

A strong signal for double parton scattering (DP) is observed in a 16 pb ^-1 sample of p¯p-->γ+3 jets+X data from the CDF experiment at the Fermilab Tevatron. The process-independent DP parameter, σ_eff, is obtained without reference to theoretical calculations by comparing observed DP events to events with hard scatterings at separate p¯p collisions. The result, σ_eff = \(14.5+/-1.7^+1.7_-2.3\) mb, represents a significant improvement over previous measurements. For the first time, the Feynman x dependence of the σ_eff parameter is investigated, and no dependence is seen.