D-meson production from 400 GeV/c p-p interactions evidence for leading di-quarks?

Results of fitting the differential distributions in xF and pT2 of D mesons produced in 400 GeV/c p-p interactions to the form View the MathML source are discussed. The D+ distribution is found to be relatively hard [n=3.1±0.8〈Pt2〉=1.32±0.27 (GeV/c)2] and the D̄0 distribution relatively soft [n=8.1±1.9,〈pT2〉=0.62±0.14 (GeV/c)2] compared to the average for all D's [n=4.9±0.5,〈pT2〉=0.99±0.10 (GeV/c)2]. It is suggested that these distributions could reflect contribution of leading di-quarks in pp collisions. Comparison is made with evidence for leading quarks in charm production in 360 GeV/cπ−p interactions