1. RPC Simulation software Raffaello Trentadue

2. RPC Digi producer RPC Digitizer RPC Synchronizer RPC Simulation model Average model Parametrized model Parametrized model Trivial model Simple model Realistic models IMPLEMENTED RPC SetUp

3. Synchronization

4. Signal delay contribution and uncertainty The time necessary to form the signal and its final resolution contains other contributions: RPC time resolution = 2 ns (due to mechanical gap tollerance) Electronic Time Jitter = 1.0 s Signal Propagation time on the strip ( speed of propagation 0.66 c) Dalay due to the cables (48 to 113 ns) The time necessary to form the signal and its final resolution contains other contributions: RPC time resolution = 2 ns (due to mechanical gap tollerance) Electronic Time Jitter = 1.0 s Signal Propagation time on the strip ( speed of propagation 0.66 c) Dalay due to the cables (48 to 113 ns) Up to CMSSW 16x no timing information was present in the simulation. The RPC Simulation software is officially in the CMSSW_1_7_0_X with the new Synchronizer class. This is important to study in the analysis the bunch crossing effect.

5. Delta Time For the single muon sample a small peak is due to few slow secondary electrons. For cosmic muons the synchronizer method failed

6. X Y Z O C = OC/v part + electronic delay Sim ReadOut Time = t.o.f. +  RPC + electronic delay 25 ns gatewidth Bunch crossing 12.5 ns bx = -1 bx = 1 bx = 0 Delta time = Sim ReadOut Time - |Delta time| < 12.5 ns BX = 0 CMS global reference frame At the moment

7. Model description RPCSimTriv: digitizes only the muon hits by assignment of the strip corresponding to the hit position. The noise is set uniform and homogeneous for all rolls. RPCSimSimple: digitizes all hits by assignment of the strip corresponding to the hit position. The noise is set uniform and homogeneous for all rolls. RPCSimParam: digitizes all hits using a global parametrization for efficiency, cluster size (exponential distribution is used). The noise is set uniform and homogeneous for all rolls. RPCSimAverage: introduces a parametrization of cluster size from MTCC experience. RPCSimAverageNoise: introduces a parametrization of cluster size from MTCC experience. Detailed noise, strip by strip is implemented RPCSimAverageNoiseEff: introduces a parametrization of cluster size from MTCC experience. Detailed description of efficiency and noise is inserted.

8. Noise for the old models

9. Muon 1 2 3 4 5 The strip corresponding to the hit extrapolated by DT reconstruction method has been identified; afterwards it has been divided in five slices in order to produce a cluster size distribution for each of them. From each distribution the mean value has been calculated as function of the slice centre position. SimAverage  newest models

10. New models of simulation

11. RPC SetUp RPCDetId_Noise.dat SimMuon/RPCDigitizer/data RPCDetId_Eff.dat ClSizeTot.dat RPCTiming.dat Geometry Roll Parameter vector MAPS Local Noise (Hz) Local Efficiency Cluster size Timing

12. RPCDetId Strips Roll name

13. Time performance TimingSimTrivSimSimpleSimParamSimAverageSimAverageNoiseSimAverageNoiseEff Min time0,0062830,0064990,0063730,0066550,0064540,006559 Max time2,173852,2373102,5266702,2041503,1212703,961170 Avg. time0,012570,0136490,0137460,0154450,0158500,015316 Tot. time125,790136,494137,458154,445158,496153,157 Noise performance: 10 Hz/cm 2 tot time = 191.633 s 100 Hz/cm 2 tot. time = 205.834 s 1000 Hz/cm 2 tot. Time = 280.491 s

14. Validation This new model has been tested in CMSSW_1_7_5 and in CMSS_1_8_0_pre5, giving the same results. I produced a profile histogram for a roll with different value of efficiency on the strips. 70% 30% 50% 100% Validation between CMSSW_1_7_5 and CMSSW_1_8_0_pre5 for the usual model RPCSimParam has been executed getting the same distributions. SEE the Twiki page

15. RPCSimDigiLink The RPCSimDigiLink is an object implemented in order to keep an association multimap- like among signal digis and simhit data. This achived goal is very important because it allows to study the more complex cases where more simhits are associated to the same rechit. This happens when delta rays are emitted giving larger cluster size. Strip numberBunch cross. Digi Many to many association RecTracks  RecHit Collection  Digis associated to a given rechit  SimHit associated to each digi  SimTrackId SimHit DetUnitId Local position Momentum Process Type Particle Type SimTrackId

16. Near future Produced several samples with more than 1000000 of events in different conditions of RPC performance: Model used SImParam: Efficiency = 100% Efficiency = 97% Efficiency = 95% Efficiency = 90% Cluster size = 1 Cluster size = 2 Cluster size = 3 Noise = 10 Hz/cm 2 Noise = 100 Hz/cm 2 Noise = 1000 Hz/cm 2 Model used SimAverageNoiseEff One layer per time swiched off

17. TWIKI PAGE The description of the RPCDigitizer package, the instructions to use it and the Validation results are reported at the following link: https://twiki.cern.ch/twiki/bin/view/CMS/MyRPCSimDigi