The most recent measurements of the top quark mass at the DØ experiment are summarized. Different techniques and final states are used and the top quark mass is determined to be mtop = 172.8 ± 1.6(stat + syst)GeV/c . In addition, a new, indirect measurement comparing the measured cross section to theoretical calculations is discussed. Both, the direct and the indirect measurement of the top qua...

The impact of improved measurements of the cross section for electron-positron annihilation into hadrons in the charm threshold region is discussed. Two aspects are studied in detail: i.) A significant reduction of the experimental error of the electronic width of the narrow resonances J/ψ and ψ and of the continuum cross section from the open charm threshold up to 4.6 GeV will lead to a corres...

The two-gluon exchange model of the pomeron is used to compute the photoproduction reaction γp → Z0p. The predicted cross section is too small to be observed at HERA, but may be detectable at an eventual Next Linear Collider.

We compute the order α2 s corrections to the one particle inclusive electroproduction cross section of hadrons with non vanishing transverse momentum. We perform the full calculation analytically, and obtain the expression of the factorized (finite) cross section at this order. We compare our results with H1 data on forward production of π0, and discuss the phenomenological implications of the ...

We show that under certain conditions a simple relationship exists between the elastic scattering of a composite halo nucleus and of its core from a stable target. The coupling of the elastic and projectile excitation channels is crucial to the analysis, which is particularly useful when the ratio of the halo to the core mass is small. In the case of Be elastic scattering the cross section rela...

Abstract. Measurements of the dependence of the J/ψ production cross section on its kinematic variables as well as on the target atomic numbers for 920 GeV/c protons incident on different targets have been made with the HERA B detector. The large collected di-lepton sample allows to study the production ratio of ψ(2S) to J/ψ and of χc to J/ψ. We also report on measurements of the bb and Υ produ...