iprimi108triggerinatlas

iprimi108triggerinatlas内容摘要：

– Combine cluster with tracks – First E/p measurements – Study calo/ID alignment 18 With pp collisions Try to see first Zee events • Start EM intercalibration – Calibrate ~400 region (D x D = x ) – ~ 250 e per region needed to achieve ctot  % – ~ 105 Z  ee events needed, ~ 104 Z will be available Likely, c ~ 1% worst case scenario: ctot  2% • cL = % measured ―online‖ nonuniformity of individual modules • cLR = % no calibration with Z  ee 19 Hadronic Calorimeters • Cell calibration: – Reference scale (starting point) for individual cell calibration = EM scale • LAr: testbeam and calibration systems: about 1% accuracy on EM scale • Tilecal: testbeam data, Cs calibration ~ % precision on EM scale • Cosmic muons, beamhalo muons – Useful in many aspects – Largon: finding dead channels, cabling errors… – Compare to muon test beam data – Possibility to trigger with Tilecal under study • Beamgas hadrons – Channel mapping。 – Study their properties and how to reject them… 20 Minimum Bias amp。 jet events • Monitoring detector response stability: with ~ 18x106 triggers to reach 1% stability • Celltocell calibration – Using phisymmetry of MB triggers, intercalibrate cells with equal dimensions/positions (2x64 cells) • Jet calibration。 based on weights estimated from Monte Carlo studies。 ingredients: – Jet fragmentation modelling: electromagic jet energy fraction, energy and multiplicity of charged hadrons, etc.. – Hadronic shower models, benchmarked in parison with test beam data。 – Description of dead material in simulation (fraction of ―lost energy‖ in dead material from ~few% to 15 %) 21 Calibration of the L1Calo system up to the start of collisions ATLAS LAr/Tile Calorimeters L1Calo Trigger TestPulses TestBeam signals at known energy TriggerInputs Calorimeter Readout Signals from beam gas collisions L1Calo Readout By using testpulses the calibration procedures can checked and first Calibration constants can be derived close to final values Beamgas collisions (onebeam running) in midDetector have the same timing as collision events the timing setup can derived and checked Calibration constants 22 Calibration of the L1Calo system up to the start of collisions Important parameters to calibrate: • Timing of input signals and timing inside the system • Transverse momentum / energy calibration • Pedestal values • Pulse shapes • Saturation values • Noise sigma Many other setup parameters needed to ensure correct dataflow in the system to be determined and checked before collisions start 23 Calibration of the L1Calo system: The first 108 triggers Z0 Calorimeter Expect about 104 Z0  e+e / 105 W  e / … Clean signals with enough statistics to: • Study the energy calibration • Verify the timing setup and event identification • Map out the threshold curves • Study trigger efficiency A rapid calibration cycle is needed especially at the beginning. 24 Muon Detector amp。 Trigger • Preliminary rt calibration of the MDT tubes。 • Calibration of the LVL1 muon trigger system: – System timing。 – Coincidence roads。 • Evaluation of the single muon trigger efficiency。 • Measurement of the cavern background level detected by the muon chambers • Measurement of the muon spectrum and parison with expectations 25 Muon Detector amp。 Trigger • MDT calibration • Chamber Alignment • Level1 Trigger cal。