Event Shapes and Power Corrections in ep DIS at HERA
  Deep-inelastic ep scattering data, taken with the H1 and ZEUS detectors at HERA, are used to study the means and distributions of the event shape variables thrust, jet broadening, jet mass, C-parameter and two kinds of differential two-jet rate. The data cover a range of the four-momentum transfer Q, taken to be the relevant energy scale, between 7 GeV and 141 GeV. The Q dependences are compared with second-order calculations of perturbative QCD. Power law corrections are applied to account for hadronization effects. 
K. Rabbertz (RWTH Aachen, Germany), U. Wollmer (DESY Hamburg, Germany)