Submitted by: Heidi Schellman, D0 QCD convener
schellman@fnal.gov  
01-(847)491-8608
01-(846)491-9982 FAX

Title:Hard Diffraction and the Pomeron 

Session: New Developments in QCD 

Abstract:
Preliminary results on jet production in antiproton-proton collisions
    at the D0 experiment indicate the presence of events with large rapidity
    intervals in the forward directon that contain essentially no deposited
    energy ("gaps"). These kinds of dijet events have been studied both at
    center-of-mass energies of 1800 and 630 GeV. The number of events with
    such rapidity gaps is significantly greater than expected purely from
    multiplicity fluctuations, and is consistent with production through          
    hard single diffraction. A class of events containing two forward gaps
    and central dijets has also been observed at 1800 GeV, and is consistent
    with hard double-pomeron exchange.