Calorimeter design & simulations for Stage I

1. Calorimeter design& simulations for Stage I Rikard Sandström University of Geneva MICE PID phone conference 2005-12-02

2. Introduction • Case studied in this talk: • Stage1 (TOFs & calorimeter only, no mag field) • Flat beam 100<pz<300 MeV/c, starting upstream of TOFs. • 6 pi mm -> Many tracks lost due to geometry • Contaminations: • Pions & pion decay products • Muon decay products • Electrons surviving momentum selection upstream very easy to filter out with TOF. • Calorimeter geometries: • KLOE light, 4 layers • KLOE light, 5 layers • Smörgås/sandwich, one 4 cm KLOE light layer • Smörgås/sandwich, one 2 cm KLOE light layer

3. Experimental setup mu pi egamma • Beam is contamined by pions and decay products from muons. • A few more complicated situations • Pions decaying to muons between TOFs • Muons missing last TOF, and giving hits from backscattering.

4. KLOE light, 4 layers Need for collimator

5. KLOE light, 4 layers Muons punching through

6. KLOE light, 5 layers

7. Smörgås, muon decay products

8. Smörgås, muon & pion Red = muon, black = pion, green = pion becoming a muon between TOFs

9. Pion-muon, KLOE light 5 layers Red = muon, black = pion, light blue = pion becoming a muon between TOFs

10. Pion muon, smörgås Red = muon, black = pion, light blue = pion becoming a muon between TOFs

11. Problem with muons at low pz Muons sometimes stop in KLOE layer Red = muon, blue = e+, green = photon

12. With 2 cm thick KLOE layer Pushes cutoff to lower p Red = muon, blue = e+, green = photon

13. Comments and future plans • All designs presented can do both positron rejection and pion rejection. • In order to justify geometry decision, I need more statistics. • (According to Alain.) How many events are needed? • Output format of G4MICE is changing as we speak. • Will take more data with the same beam once software is again stable.