Status of MuCh simulations at CBM

1. Status of MuCh simulationsat CBM Anna Kiseleva

2. Outline • Muon measurements at CBM • Segmentation of muon system • Time measurements • Next steps

3. CBM 2006 STS MuCh TRD ToF CBM Collaboration Meeting Febr. 2007

4. Muon Chambers 20 20 20 30 35 cm Fe Fe Fe Fe Fe 260 cm 5 cm 0 cm 102.5 cm

5. Hard muon tracks μ+ ρ μ-

6. Parameters of detectors 2006 • STS: • stsDigiVersion = "v05a" • 2 hybrid + 4 strip detectors • MuCh: • 100 μm space resolution • 80 πsec time resolution • ToF: • 6 mm  7 mm space resolution • 80 πsec time resolution

7. Results from Coll. Meet. Febr.07 hard-hard pairs without cuts ————— S/B ratio ——————————————————————— ω φ η ηDalitz ρ ω φ η ηDalitz ρ = 0.2 = 0.05 = 0.004 = 0.05 = 0.003 = 2.6 = 5.2 = 1.2 = 0.3 = 2.2 [0.2; 0.3] GeV/c2 [0.2; 0.9] GeV/c2 ————— Efficiency (%) —————————————————————

8. CBM 2007 STS MuCh ToF

9. Parameters of detectors 2007 • STS: • STS digitizer • 6 strip detectors • MuCh: • MuCh digitizer • 80 πsec time resolution • ToF: • 6 mm  7 mm space resolution • 80 πsec time resolution

10. Detector segmentation min pad 1.4  2.8 mm2 space resolution: x – 400 μm, y – 800 μm 5% occupancy max pad 44.8  44.8 mm2 space resolution: x – 12.8 mm, y – 12.8 mm Mikhail Ryzhinskiy, Saint-Petersburg State Polytechnical University

11. Results hard-hard pairs 100 μm new ————— S/B ratio ——————————————————————— ω φ η ηDalitz ρ ω φ η ηDalitz ρ = 0.2 = 0.05 = 0.004 = 0.05 = 0.003 = 2.6 = 5.2 = 1.2 = 0.3 = 2.2 = 0.07 = 0.02 = 0.002 = 0.02 = 0.001 = 2.4 = 4.8 = 1.0 = 0.2 = 2.0 [0.2; 0.3] GeV/c2 [0.2; 0.9] GeV/c2 ————— Efficiency (%) —————————————————————

12. Reconstructed bg —μ —π —Κ —p —ghost

13. Weak decays absorber pad

14. Weak decays absorber pad

15. Ideas of new possibilities • set min space resolution: • for X and Y separately • for each detector triplet • set angle of detector rotation

16. Time measurements

17. —μ —π —Κ —p —ghost Reconstructed bg

18. Time measurements P = mμ × β × γ β = , t - time γ = L (L, t) c × t 1 √1 – β2 STS MuCh ToF (L, t) PSTS

19. Comparison time measurement at the 3 m time measurement at the 10 m signal μ bg μ signal μ bg μ PToF π K π K p ghost p ghost PSTS

20. time information —μ —π —Κ —p —ghost —μ —π —Κ —p —ghost Reconstructed bg cut of Pmuon ToF

21. —without cut —with cut of Pmuon ToF —with cut of PToF Reconstructed signals

22. Results hard-hard pairs without PmuonToF PToF cuts cut cut ω ω = 0.06 = 2.4 = 0.14 = 2.1 = 0.14 = 1.2 ————— S/B ratio ———————————————————— ————— Efficiency (%) ——————————————————

23. Detector requirements • high rate capability (up to 1 MHz/cm2) • high granularity (up to 1 hit/cm2s-1 for central Au+Au collisions) • position resolution < 300 μm • 3 space points between absorbers • full detector thickness < 5 cm • possibility of the time measurements

24. Next steps • Continue of the detector space resolution study • Optimization of ToF for the muon measurements