1. HBD performance study during run9 pp 200GeV Katsuro Nakamura 1

2. HBD Sdphi, Sdz stability check during Run-9 Sdphi, Sdz … distance between track and cluster, normalized with RMS used whole electron tracks in EWG_DST on CCJ 2

3. electron track selection – abs(bbcz)<20cm – quality==31||51||63 – pt>0.15GeV/c – n0>=2 – prob>0.01 – abs(emcsdphi_e)<4, abs(emcsdz_e)<4 – e/p>0.6 – hbdsize>=2 3

4. Sdphi fitting fit with gaus + pol1 – check the run dependence of mean and sigma of gaus 4

5. Sdphi 0.0 < pt < 0.5 GeV/c0.5 < pt < 1.0 GeV/c 5 mean sigma mean sigma

6. Sdphi 1.0 < pt < 1.5 GeV/c1.5 < pt < 2.0 GeV/c 6 mean sigma mean sigma

7. Sdz fitting fit with gaus + pol1 – check the run dependence of mean and sigma of gaus z 7

8. Sdz 0.0 < pt < 0.5 GeV/c0.5 < pt < 1.0 GeV/c displacement of mean value  recalibrate this value (but this displacement is enough small to be ignored.) 8 dynamical moving during run-9 ? mean sigma mean sigma

9. Sdz after private recalibration 0.0 < pt < 0.5 GeV/c0.5 < pt < 1.0 GeV/c new_sdz = (sdz - mean)/sigma 9 mean sigma mean sigma

10. Sdz 1.0 < pt < 1.5 GeV/c1.5 < pt < 2.0 GeV/c 10 mean sigma mean sigma

11. Sdz after private recalibration 1.0 < pt < 1.5 GeV/c1.5 < pt < 2.0 GeV/c 11 mean sigma mean sigma

12. Sdz private recalibration parameters runnumberpt [GeV/c]meansigma 281800 ~ 2828000.0 < pt <= 0.50.11471.030 0.5 < pt <= 1.00.098531.019 1.0 < pt <= 1.50.080101.002 1.5 < pt0.070610.9853 282800 ~ 2851600.0 < pt <= 0.50.13701.030 (same) 0.5 < pt <= 1.00.12691.019 (same) 1.0 < pt <= 1.50.11351.002 (same) 1.5 < pt0.10440.9853 (same) 285160 ~ 2871000.0 < pt <= 0.50.22141.030 (same) 0.5 < pt <= 1.00.21701.019 (same) 1.0 < pt <= 1.50.19971.002 (same) 1.5 < pt0.19180.9853 (same) 287100 ~ 2915000.0 < pt <= 0.50.24861.030 (same) 0.5 < pt <= 1.00.23481.019 (same) 1.0 < pt <= 1.50.22051.002 (same) 1.5 < pt0.21500.9853 (same) 12

13. HBD calibration check for electron track 13

14. electron track selection – abs(bbcz)<20cm – quality==31||51||63 – pt>0.15GeV/c – n0>=2 – prob>0.01 – abs(emcsdphi_e)<4, abs(emcsdz_e)<4 – e/p>0.6 – hbdsize>=2 – abs(hbdsdphi)<4, abs(hbdsdz)<4 14

15. electron track distribution electron track dist. on sect9 is almost uniform. pad id (0-origin): 96 97 98 …………… Sect 9 South 15 fill hbdcharge to the nearest pad from p = {phbdx, phbdy, phbdz}. ///////////////////////////////// int padnum = NearestPad(phbdx,phbdy,phbdz); hist[padnum]->Fill(hbdcharge); /////////////////////////////////

16. I found the update of HbdWisClustrizer.C on CVS HbdWisClustrizer.C – define clustering algorithm HbdWisClustrizer.C –r1.12 (previously used) – cause nonuniform cluster peak distribution detail is in slide sent to electron-l on 5/ 6/ 2010  update HbdWisClustrizer.C –r1.16 (latest version) – looks fine! 16

17. peak pad distribution after update reasonable distribution 17 fill hbdcharge to the peak pad in the cluster ////////////////////////// int max_pad = peak pad in the cluster; hist[max_pad]->Fill(hbdcharge); ////////////////////////// pad id (0-origin): 96 97 98 …………… Sect 9 South

18. sector-by-sector HBD charge dist. for single e and double e 18

19. Dalitz Electron Pair Selection Electron Selection – bbcz < 20 cm – quality==31||51||63 – pt>0.15GeV – n0>=2 – abs(emcsdphi)<4.0, abs(emcsdz)<4.0 – prob>0.01 – e/p>0.6 – hbdsize>=2 – abs(hbdsdphi)<4.0, abs(hbdsdz)<4.0 Pair Selection – Mass<0.15GeV/c^2  select Dalitz region – PhiV cut  reject conversion pairs – Unlike sign 19

20. Single e and Double e definition Single hbd_id(trk_i) != hbd_id(trk_j) Double hbd_id(trk_i) == hbd_id(trk_j) π trk_i trk_ j π trk_i trk_ j 20 notice: used HbdWisClusterizer.C –r1.12 in the following analysis

21. HBD charge distribution (East Arm) for Dalitz event (Raw dist.) Sect 0 1 2 3 4 5 Direction NS N S blue: single red : double 21

22. HBD charge distribution (West Arm) for Dalitz event (Raw dist.) Sect 6 7 8 9 10 11 Direction SN S N 22 blue: single red : double

23. HBD charge distribution (East Arm) for Dalitz event (normalized) normalized with integral of entry Sect 0 1 2 3 4 5 Direction NS N S 23 blue: single red : double difficult to use slightly worse slightly worse

24. HBD charge distribution (West Arm) for Dalitz event (normalized) normalized with integral of entry Sect 6 7 8 9 10 11 Direction SN S N 24 blue: single red : double

25. comparing with the distribution made by Ilia good agreement singledouble HBD charge distribution π e+ e- HBD charge distribution D e Dalitz event pair mass ~ 0 field ~ 0 by I.Ravinovichi 25

26. For the next step study Pt dependence of the ratio between single and double. – low pt  2 clusters tend to be separated – high pt  2 clusters tend to be merged decide charge threshold sector-by-sector 26

27. backup slide 27

28. HBD scintillation charge distribution fit with a0*exp(-x/a1) a0 = const, a1 = slope 28 fit on 2.5 ~ 5 [p.e.]

29. run dependence of fitting slope it’s stable – since it’s calibrated no large difference on pad-by-pad – also “const” has no large difference HBD sect9 Yellow: pad107 Red: pad127 Blue: pad106 Green: pad105 29

30. central pad in cluster you can see the pad dependence of yielded charge Sect 9 South pad id (0-origin): 96 97 98 …………… 30