1. Realistic detector layout for MUCH system M.Ryzhinskiy, SPbSPU CBM Collaboration Meeting September 25-28, 2007, Dresden, Germany

2. Topics to cover Goals & problems Proposed solutions Future improvements Summary CBM Collaboration Meeting, 25-28 September, 2007 Mikhail Ryzhinskiy

3. Ideal case: More realistic case needed: optimal parameters (channel number, granularity, …); ability to work in CBM exp.; consensus between the price and functionality. Goals dx=dy=100µ dx dy CBM Collaboration Meeting, 25-28 September, 2007 Mikhail Ryzhinskiy

4. Hit density (HD) challenge HD max  0.8 hits/(event*cm 2 ) HD(R 1 ) = HD max /2; HD(R 2 ) = HD(R 1 )/2; ….. HD(R n ) = HD(R n-1 )/2. CBM Collaboration Meeting, 25-28 September, 2007 Mikhail Ryzhinskiy

5. Circled regions R 1 R 2 …….. R n occupancy  0.05 CBM Collaboration Meeting, 25-28 September, 2007 Mikhail Ryzhinskiy

6. Segmentation Station  Sectors  Pads 128 channels/sector PAD min : 0.14x0.28 cm 2  SECTOR min : 2.24x2.24 cm 2 S i pad/sec =2*S i-1 pad/sec CBM Collaboration Meeting, 25-28 September, 2007 Mikhail Ryzhinskiy

7. Hit distribution CBM Collaboration Meeting, 25-28 September, 2007 Mikhail Ryzhinskiy

8. Terminology Layer Stations Layer  Station  Sector  Pad CBM Collaboration Meeting, 25-28 September, 2007 Mikhail Ryzhinskiy

9. Disadvantages & possible solution Strip-like pads (strips): width = 0.14 cm = const length i =2*length i-1 Hybrid stations: pads in central region + strips in peripheral region  9 stations CBM Collaboration Meeting, 25-28 September, 2007 Mikhail Ryzhinskiy

10. Simple hit producer (pads) Event display by E. Kryshen CBM Collaboration Meeting, 25-28 September, 2007 Mikhail Ryzhinskiy

11. Avalanches CBM Collaboration Meeting, 25-28 September, 2007 Mikhail Ryzhinskiy

12. Advanced algorithm CBM Collaboration Meeting, 25-28 September, 2007 Mikhail Ryzhinskiy primary electrons sec. electrons

13. Running a segmentation CbmMuchSegmentation* muchSegmentation = new CbmMuchSegmentation(); // Set number of layers muchSegmentation->SetNLayers(5); // Set filename where to store parameters muchSegmentation->SetDigiFileName(“much.digi.par”); // Set minimal resolution for a detector layer muchSegmentation->SetMinSigmaX(1, 400); muchSegmentation->SetMinSigmaY(1, 800); // Set rotation angle muchSegmentation->SetAngle(1, 10); // Make segmentation muchSegmentation->SegmentMuch(); CBM Collaboration Meeting, 25-28 September, 2007 Mikhail Ryzhinskiy

14. Running the digitizer // --- MuCh digitizer ---------------------------------------- CbmMuchDigitize* muchDigitize = new CbmMuchDigitize("MuchDigitize", iVerbose); muchDigitize->SetUseAvalanche(0); // Not account for avalanches muchDigitize->SetDTime(8e-2); // Set time resolution fRun->AddTask(muchDigitize); // ------------------------------------------------------------ // --- MuCh hit finder --------------------------------------- CbmMuchFindHits* muchFindHits = new CbmMuchFindHits("MuchFindHits", iVerbose); fRun->AddTask(muchFindHits); // ------------------------------------------------------------ CBM Collaboration Meeting, 25-28 September, 2007 Mikhail Ryzhinskiy

15. Next steps Fix parameters (resolution, angles …) Consider strip-like pads (if needed) Segmentation to the simulation stage Cluster finder CBM Collaboration Meeting, 25-28 September, 2007 Mikhail Ryzhinskiy

16. Summary Segmentation procedure is provided Simple digitizer for MuCh is provided Proposed different segmentations Advanced digitizer is developed Compatibility with new CBMROOT release CBM Collaboration Meeting, 25-28 September, 2007 Mikhail Ryzhinskiy