The CMS production system has undergone a major architectural upgrade from its predecessor, with the goal of reducing the operational manpower needed and preparing for the large scale production ...required by the CMS physics plan. The new production system is a tiered architecture that facilitates robust and distributed production request processing and takes advantage of the multiple Grid and farm resources available to the CMS experiment.
The alignment uncertainties of the CMS tracker detector, made of a huge amount of independent silicon sensors with an excellent position resolution, affect the performances of the track ...reconstruction, the track parameters measurement and the vertex reconstruction. In order to study the impact of the misalignment of the CMS tracking devices on the previous procedures, realistic estimates for the expected displacements of the tracking systems are supplied in two different scenarios, the first supposed to reproduce the misalignment conditions during the first data taking while the second one related to long-term data taking condition. Results on the track reconstruction are expressed in terms of the resolution on track parameters, the global efficiency of the track reconstruction and the fake rate in the two scenarios of misalignment, by comparing them with the scenario of a perfect alignment of the tracking devices. Primary vertex finding efficiency and position resolution are affected by the tracker misalignment, too.
Monte Carlo production for the CMS experiment is carried out in a distributed computing environment; the goal of producing 30M simulated events per month in the first half of 2007 has been reached. A ...brief overview of the production operations and statistics is presented.
The MEG-II experiment searches for the lepton flavor violating decay: mu in electron and gamma. The reconstruction of the positron trajectory uses a cylindrical drift chamber operated with a mixture ...of He and iC4H10 gas. It is important to provide a stable performance of the detector in terms of its electron transport parameters, avalanche multiplication, composition and purity of the gas mixture. In order to have a continuous monitoring of the quality of gas, we plan to install a small drift chamber, with a simple geometry that allows to measure very precisely the electron drift velocity in a prompt way. This monitoring chamber will be supplied with gas coming from the inlet and the outlet of the detector to determine if gas contaminations originate inside the main chamber or in the gas supply system. The chamber is a small box with cathode walls, that define a highly uniform electric field inside two adjacent drift cells. Along the axis separating the two drift cells, four staggered sense wires alternated with five guard wires collect the drifting electrons. The trigger is provided by two 90Sr weak calibration radioactive sources placed on top of a two thin scintillator tiles telescope. The whole system is designed to give a prompt response (within a minute) about drift velocity variations at the 0.001 level.
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