1 G4MICE downstream distributions G4MICE plans Rikard Sandström Universite de Geneve MICE collaboration meeting 27/6-05

2 Outline Comments on yesterdays talk Downstream distributions Planning ahead Conclusion

3 Comments from yesterday The max energy RF induced photons is 7.04 MeV upstream, 2.04 MeV downstream. –Opposite for mu- beam. –Based on RF phases ideal for 200 MeV mu+. If not using NN, we are stuck with the plot to the right. (Best two variables vs each other.) –Still need to refit if assumptions change.

4 Downstream distributions Where do muons decay? –(Where is background?) In flight looks as expected. –One exception: CKOV2 looses events, both background and muons. –Threshold in digitization? –Too small aperture? Beam 3.3 pi mm rad: Digitized!

5 At 10 pi mm rad, 30 MeV/c pz RMS After digitization –Removes hits if not > threshold, within sampling period. –TrackRefDown has no such cut. –EMCal does. –Others?

6 TOF2 x-y distribution

7 CKOV2 x-y distribution

8 Calorimeter x-y distribution

9 End of first part, comments Are these numbers indicating problems? –Detector people should check their geometry and digitization. Are the transversal sizes what we want? What we need?

10 Planning ahead, calorimeter Add TDC info –Requires input from hardware people. Reproduce KLOE situation, validate. Find memory leak. Add TOF2RefPlane, mod PrimaryGeneratorAction –Yagmur/Rikard? Run 10 mm pi rad with ~ 1M events. –Might need more processor power. Expect 1 month if not. Try out different geometries, starting at TOF2. –3 cm cells –Sandwich (range based) –Smörgås (no decay at rest)

11 Planning ahead, downstream PID Find reasonable cuts. –Ex. Tof light speed. Try NN with fewer, smarter variables. (Based on expectations.) –Expected TOF. (p_z, t) –Expected range in calorimeter. (p, z_cal) –Expected total ADC counts. (p_t, p_z, adc_cal) –Should primarily improve calorimeter performance, but wont be possible in Step I. Look for systematic errors, bias. –Requires larger sample. Should G4MICE PID use NN? –Two independent macros, one could be built into mice2root. –The 3 rd, the analyzer is fast and can be used on the fly.

12 Planning ahead, spill structure Add option to run MICESpill, not only MICEEvent. Need decision on trigger! How to set RF phases? Converge with Malcolm et al. –Need a dedicated meeting. Detector code might need to change. –Only TPG OK already to my knowledge.

13 Planning ahead, run all BG When we can do spill, run with: A –EMCal, how well can it handle multiple events, pile up etc. B –Beam starting at TOF1. –Diffuser, iron shield etc. –Pion contamination (decay on) –Muon decay on –RF bg from background bank –Taking p_t, p_z and TOF from real reconstruction. –Result: realistic emittance resolution! One year from now?

14 BeamTools migration Chris requires new Optics package independent of Geant4 Must do complete remake of BeamTools(Chris) and EngModel(Rikard). Must take care not to break anything! –Need a mini workshop between Chris, Yagmur, Rikard.

15 Code cleanup The dirty trio 1.MICESFoFoConstruction –Cooling channel 2.MICESteppingAction –Tracking 3.MICEPrimaryGenerator –How we create the beam

16 Physics in Geant4.7 Check Bill Murray’s statement about discrepancies between Geant4.7.0.p01 and Geant4.6.2.p02. Update MICEPhysicsList. –When moving to G4.7.

17 MICE notes Write a MICE note on calorimeter simulations. When we go to Geant4.7, rerun RF background, update note with MTA measurements. A TPG note? Documentation for everything!

18 Conclusion G4MICE is getting useful for detector R&D. Though schedule –Please get more people into G4MICE!