Measurement of dijet production with a veto on additional central jet   activity in pp collisions at 7 TeV using the ATLAS detector
  A measurement of jet activity in the rapidity interval bounded by a dijet system is performed using pp collisions at 7 TeV recorded by the ATLAS detector in 2010. The data are compared to LO predictions from PYTHIA, HERWIG++ and ALPGEN event generators. The data are also compared to NLO parton shower prediction from POWHEG, when interfaced to PYTHIA or HERWIG parton shower, and all order resummation prediction from HEJ. In most of the phase-space regions presented, the experimental uncertainty is much smaller than the spread of LO Monte Carlo event generator predictions. In general, POWHEG+PYTHIA gave the best description of the data. 
P. Bernat
hep-ex