1. Dmitri Ossetski Obninsk State University Department of Applied Mathematics e-mail: ossetski@obninsk.ruossetski@obninsk.ru

2. D. Ossetski, Obninsk State University Compressed Baryonic Matter 2 The Setup Consist of: Target & Beam, Superconducting Dipole Magnet, Silicon Tracking System (STS), Rich Imaging Cherenkov Detector (RICH), Transition Radiation Detectors (TRD), Resistive Plate Chamber (RPC), Electromagnetic Calorimeter (ECAL), HADES spectrometer. Sketch of the planned CBM experiment

3. D. Ossetski, Obninsk State University 3 The layout of the Si-Strip STS4 and STS6 Planes FeatureValue/Quantity Angular coverage50 to 500 mrad Number of super layers 4 Detector modules per plane 28-60 Detector thickness≤ 100-150 µm Sensitive detector area 20x20 cm 2 to 50x50 cm 2 Operational temperature ≤40°C Strip pitch25 µm Summary of Si-Strip STS Si-Strip sensors are oriented radially.

4. D. Ossetski, Obninsk State University 4 - number of real hits real hits fake hits Total Points Fake Hits Real Hits

5. D. Ossetski, Obninsk State University 5 - pitch of Si-Strip sensors - stereo angle CBM x y

6. D. Ossetski, Obninsk State University 6 Principal idea Getting Hits. 3D "projection" of MCPoint on Si-Strip grid.

7. D. Ossetski, Obninsk State University 7 Find hits (real and fake) corresponding to active intersecting strips Find all strips activated by points for every event real hits fake hits 1 2 FOR EACH EVENT WITH ARRAY OF ACTIVE STRIPS 1. Find place of intersection of pair of Strips 2. Generate Hit on that place 3. Save Hit info fX, fY, fDx, fDy FOR EACH POINT 1. If it belongs to Si-Strip STS 2. Find current Si-Strip plate 3. Find current wafer 4. Find nearest to the Point vertical & inclined strips 5. Save active strips info to Array Find Strips Find Hits

8. 8 Point distribution for 1 event at 4 Si-Strip STS super layers cm Z=40 cm Z=60 cm Z=80 cm Z=100 cm Simulation based on GEANT4 within the CBM virtual Monte Carlo framework were performed in order to optimize the layout of the Si- Strip tracker.

9. 9 Hit distribution for 1 event at 4 Si-Strip STS super layers Z=40 cm Z=60 cm Z=80 cm Z=100 cm cm

10. 10 Charged particles occupancy in Si-Strip STS central region 20 x 20 cm, 4 stations, 100 events

11. 11 1 cm of central parts along X Charged particles occupancy in the four Si-Strip planes as function of the horizontal distance from the beam centre

12. 12 1 cm of central parts along X Charged particles occupancy in the Si-Strip STS4 and STS7 as function of the horizontal distance from the beam centre

13. 13 DeltaX, DeltaY between points & real heats in STS4 inner wafer

14. 14 DeltaX, DeltaY between points & real heats in STS4 inner wafer

15. D. Ossetski, Obninsk State University 1.Continue working on Si-Strip STS tracker 2.Going to install CBM VMC software at Obninsk University