Thrust jet analysis of deep-inelastic large-rapidity-gap events

A thrust analysis of Large-Rapidity-Gap events in deep-inelastic collisions is presented, using data taken with the H1 detector at HERA in 1994. The average thrust of the final states , which emerge from the dissociation of virtual photons in the range , grows with hadronic mass and implies a dominant 2-jet topology. Thrust is found to decrease with growing , the thrust jet momentum transverse to the photon-proton collision axis. Distributions of are consistent with being independent of . They show a strong alignment of the thrust axis with the photon-proton collision axis, and have a large high tail. The correlation of thrust with is similar to that in annihilation at , but with lower values of thrust in the data. The data cannot be described by interpreting the dissociated system as a state but inclusion of a substantial fraction of parton configurations leads naturally to the observed properties. The soft colour exchange interaction model does not describe the data.