At CERN
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At CERN. Plus side slice test (downstairs) Working gas mixture (Ar-CO 2 -CF 4 ) in system… ready for HV Thursday will look at cosmics downstairs with layer trigger Cooling still an issue for USC (computers, FED and TF crates) LV still an issue… CSC simulation
At CERN
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At CERN • Plus side slice test (downstairs) • Working gas mixture (Ar-CO2-CF4) in system… ready for HV • Thursday will look at cosmics downstairs with layer trigger • Cooling still an issue for USC (computers, FED and TF crates) • LV still an issue… • CSC simulation • Attempt to compare simulation with data available with regards to timing… G. Rakness (UCLA)
Couple of details while looking at drift times from simulation… • Recall, “knobs” in CSC simulation are… • bunchTimingOffsets[chamber type] • Shifts all chambers of a given type by a constant amount (nsec) • ME1/1 have narrower wire spacing (2.5mm 3.1mm for other chambers), so drift is different for ME1/1/ chambers… • timeBitForBxZero • Global offset for all wireHits from all chambers (bx)…irrelevant… • tofOffset • One correction per wiregroup (per chamber) (nsec) • Compensates for TOF for muons originating at z=0 • Remove this correction so drift times from all chambers can be combined (except ME1/1, of course…) • Smearing parameter to smear arrival time from each wire (at ALCT…) • Default value = 0… G. Rakness (UCLA)
Analysis of Cosmic Ray Data… Remember August 1998? http://www-hep.phys.cmu.edu/cms/TALKS/DOE_98_v3_www.ps N. Terentiev (CMU) • Good fit by “semi-gaussian” = Gaussian with 2 independent widths… allowed to be different on one side of the centroid from the other • P2 = 7.8 nsec • P3 = 12.7 nsec G. Rakness (UCLA)
Simulation with smearing… • Recall, data had… • P2 = 7.8 nsec • P3 = 12.7 nsec • No tails • WITH inclusion of smearing parameter of 2.2nsec, simulation has: • P2 = 6.1 nsec • P3 = 11.8 nsec • Long tail to high end • ME1/1 peak = 28.7 nsec • other CSCs’ peak = 37.3 nsec G. Rakness (UCLA)
Arrival times for data… N. Terentiev (CMU) • With N_layers >=4, the arrival of the data from the n-th layer is… • smoothly increasing from mean of 45 57 nsec • sigma ~ 5nsec for all hits http://www-hep.phys.cmu.edu/cms/TALKS/emu1_00_sep_teren.html G. Rakness (UCLA)
Arrival times for simulation… • WITH smearing of 2.2nsec, the simulation has… • smoothly increasing mean from 32 44 nsec • sigma ~ 4.6-5.2 nsec • Without smearing, the simulation has • sigma ~4.1-5.1 nsec… G. Rakness (UCLA)
To do… • Push Heavy Stable Charged Particles through simulation and see how well emulator does at creating: • CLCT • ALCT • LCTs matched at TF… • Check to see if, in this idealized case, HSCP’s will make it through the CSC trigger… G. Rakness (UCLA)