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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
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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)