1. Particle Identification in CBM ● Geometry and acceptance at 25 AGeV ● Hadron identification - TOF performance - Matching to the Silicon Tracker ● Summary K. Wisniewski, FOPI Coll., Uniwersytet Warszawski, Universität Heidelberg

2. Silicon tracker - p determination - sec. vertex Electrons - RICH, TRD Hadrons - Time of Flight (RPC) Geometrical acceptance :  lab 5 – 30 o (New) CBM Geometry

3. Hadron identification up to 5 GeV/c K/  separation up to 5 GeV/c  large distance from the target  large scale (high cost) High-rate capability (up to 20 kHz/cm 2 ) Good time resolution Phase-space Distribution at 25 AGeV

4. TOF wall located 15 m from target K,  yields from UrQMD, Au+Au,25AGeV S/B depends on TOF resolution Required S/B for K : 10 K/  separation with 80ps device: up to 4 GeV/c Hadron Identification by TOF

5. ● Good mid-rapidity coverage ● D 0 detectability as low as 10% (p max =4 GeV/c) ● Factor 3 better with p max =6 GeV/c  As good as poss. time resolution needed D 0 Efficiency

6. FOPI Strip-Anode ALICE Pad-Anode Very good time resolution Negligible tails High efficiency High granurality Low cost High-rate capability is a problem (2 kHz/cm 2 )  A4 glass  geometry optimisation Ageing needs to be tested Timing Multi-gap Resistive Plate Chambers

7. ● Extrapolation over 5 m. of RICH ● Perfect position resolution assumed Matching distorted due to mult. scattering Accuracy of the extrapolation depends on distance Matching to the Silicon Tracker

8. ● Hit-search radius 2  x,y (86% efficiency): 2  0.18cm (1 GeV/c) 2  0.09cm (2 GeV/c) ● Biggest confusion close to the target (Silicon) and at small angles (  5 o ) ● Double hit probability at  5 o : 15% (1 GeV/c) 4% (2 GeV/c) ● Misidentification probability (15%)/2 (with no background particles) Efficiency and Misidentification

9. ● PID needs a good tracking system (avoid large gaps) optimisation of RICH (splitted into two parts) tracking on the way to TOF (additional TRD stations) ● TOF-based PID limited to 4-6 GeV/c (for K/  separation) ● Good coverage of the D 0 phase-space distribution (mid-rapidity) ● D 0 efficiency 10-30% (depending on p max )  go for as good as possible TOF resolution  use other technique for the K/  separation at high p (RICH?) Summary

10. Monolithic Activ Pixel Sensors (MAPS) Excelent hit resolution (3  m) Small thickness (20  m) Not radiation-hard Slow readout