1. Hit Efficiency Study Yukio FUJIYAMA (Tokyo Tech)

2. Definition of Hit Efficiency Definition Number of the intersections of tracks (Rec_TRK) with layers →denominator Coincidence of clusters in table (RecSVD_Cluster_select) →numerator

3. Hit efficiency study I calculated the hit efficiency with the data of no- background. 1 st layer 0.888±0.002 2 nd layer 0.890±0.002 3 rd layer 0.916±0.002 4 th layer 0.889±0.002 There is no difference of hit efficiency between layers.

4. Residual Distribution I checked residual distribution of localx and localz for each occupancy. Definition DSSD localx localz Track I estimated residual Cluster position (RecSVD_Cluster_Select) Cluster position I estimated

5. Residual Distribution Low occupancy : occupancy<5% High occupancy : occupancy>20% Sigma Low occupancyHigh occupancy 0.7591×10 -3 0.8657×10 -3 0.1177×10 -2 0.1209×10 -2 0.1074×10 -2 0.1101×10 -2 0.1144×10 -2 0.1145×10 -2 Sigma Low occupancyHigh occupancy 0.1385×10 -2 0.1672×10 -2 0.2422×10 -2 0.2747×10 -2 0.2320×10 -2 0.2393×10 -2 0.2599×10 -2 0.2520×10 -2 N-side P-side I used gaussian fit. 1 st 2 nd 3 rd 4 th

6. Summary I calculated the hit efficiency with the data of no- background. There is no difference of hit efficiency between layers. There is no doubt that the value of efficiency decrease because of the high occupancy. I checked residual distribution of localx and localz for each occupancy. The sigma of gaussian fit for low occupancy is better than that for high occupnacy.