1
LOCH LEMAN MONSTER Drift Tubes in CMS at LHC Where 100 m underneath Earth, near a city called Geneva, a 27 km tunnel hostes 4 of the greatest monsters of nature. 10 11 protons are bolted down 40 million times a second by these monsters. Within it, a milliard of particles are created, making its diet very divers (muons, neutrinos, s-particles… Higgs bosons?) diet This cilinder-shaped monster with the size of a 5-story building is supposed to live inside the tunnel. The particles created after the collision are bended due to its solenoidal B field, identiying them and measuring their momenta CMS Muons are an essential part in CMS diet. They are a very clear signal to detect more interesting particles such as the Higgs boson or s-particles. Muons are detected in DT, RPC and CSC stomachs. DT CRUZET AND CRAFT DRIFT VELOCITY DT CHAMBER EFFICIENCY There are 250 DT chambers in CMS, 25% built in CIEMAT (Madrid) MB4 MB3 MB2 MB1 S5 DT CALIBRATION drift TDC v t t x ) ( 0 Calibration Transformation from time to position Time measured in DT cell μ μ t0 calibration vd calibration Detection in a DT cell My fight against the monster μ trigger Eff vs #hits Eff vs pt B field effect Efficiency ) / ( 21000 max ns m T v drift 2 3 1 2 t t t T ) ( max MUONS in cms Javier Santaolalla, SUSSP 2009, St Andrews MB2
