1. Update on final state study Jaewon Park University of Rochester MINERvA/Jupiter Group Meeting, Aug29, 2007

2. 2 Multiple clusters Gamma track is broader than proton or muon Tracker processes only first cluster currently  Second cluster is ignored cluster single hit

3. 3 Kalman Filter with multicluster top vview top vview After Before Slight more straight, fitting stops eariler Fitter seems to stop to fit points when the track become broader. But I haven’t found the criteria to stop fit points

4. 4 Number of reconstructed gamma tracks gamma1gamma2 gamma1gamma2 After Before Modified tracker he lped more on gamm a1 but not much on gamm2 Gamm1,gamma2 is order gammas by tr ue energy scale. Before: original trac ker After: modified trac ker that allows mult iple cluster

5. 5 Gamma track efficiency BeforeAfter

6. 6 Proton track efficiency Almost no difference before and after

7. 7 Pi0 mass reconstruction using gamma track This is an optimal case: Two gamma tracks are reconstructed Not too much difference before and after After Before

8. 8 Average cluster size This values corresp onds track fuzziness roughly when track angle to z-axis is sm all Gamma shows muc h broader distributio n than proton After Before p p Average cluster size = (total nStrips)/(number of coordinate)

9. 9 dE/dx (energy deposit sum)/(reco track length) No event selection is used. Gamma and pion dE/dx distribution are similar.