Virtualisation of Grid Resources and Prospects of the Measurement of Z Boson Production in Association with Jets at the Large Hadron Collider

At the Large Hadron Collider (LHC), a large number ofevents containing Z bosons will be available and thecalibration of the absolute jet energy scale withthese events becomes feasible for the first time.Such a calibration is important as the uncertainty onthis observable will be the dominant systematicaluncertainty on most LHC analyses. This workdemonstrates the feasibility of such a calibrationwithin the CMS experiment through a comparison of themomentum of a jet with the precisely reconstructedmomentum of a Z boson decaying into two muons. Thefour LHC experiments will produce about 15 petabytesof data annually which are stored and processed usinggrid technologies. This, however, requires additionalservices which do not fully load server machines atsmaller grid sites. The virtualisation of operatingsystems enables the consolidation of differentservices on a few server machines. Extending thisconcept to batch queuing systems allows overcomingintrinsic limitations of shared computinginfrastructures. Both, the consolidation of aninstitute''s computing and grid infrastructure and aprototype implementation of a virtualised batchqueuing systems are presented.... Mehr