1. BesMUC Reconstruction Current Status You zhengyun, Mao yajun School of Physics, PKU 2003.12.31

2. BesMUC Reconstruction BesMUCRec HitContainer BesMUCRec Geometry BesMUCRec GapGeo BesMUCRec StripGeo BesMUCRec SoftID Geometry Data BesPersEvent Simu Event Data BesMUCRec Hit BesMUCRec 2DRoad BesMUCRec 3DRoad BesMUCRec 2DRoadContainer BesMUCRec 3DRoadContainer contains BesMUCRec HitID BesMUCRec RoadFinder

3. RoadFinder 1.one 3D Road is a combination of two 2D Roads; Barrel : Z-R road + φ -R road; Endcap : Z-X road + Z-Y road; 2.temporarily, only search roads on each segment; 3.start from two seed gaps in one 2D road; 4. each possible combination of two 2Droads forms one 3D road; 5.use cut to eliminate ghost roads; not enough information …

4. √ xx √ Search window Use cut to eliminate ghost roads RoadFinder Algorithm Attach hits, Fit, and go on … Seed gaps Fired strips

5. ex1 : single track on one segment Simulation track φ -R view Z-R view

6. Find φ -R road Find Z-R road Combine two 2D roads Event display : reconstruct track Fired strips

7. Simu vs. Reco

8. ex2 : two tracks on one segment Simulation tracks Z-R view φ -R view

9. Fired strips Find φ -R roads Find Z-R roads Combine two 2D roads Event display : reconstruct tracks

10. Real tracks Ghost tracks We need extrapolated MDC tracks to eliminate ghost tracks

11. Simu vs. Reco

12. A simple reco ratio test Simu : 1000 events : single mu-, p = 2Gev cos θ ( -0.8 ~ 0.8) φ ( 0 ~ 2 π ) no noise added Reco : read in 947 simu events with hits; in 811 events, 3D road is reconstructed ; ratio 86% Need to check and optimize …

13. Bes Muon Chamber offline software has possessed basic functions. Generate Simu Data Simu Data IO Reconstruct tracks Event Display Lots of improvement to make. usable  excellent Summary