1. D. Elia, INFN BariALICE Offline Week - June 20041 Recent results from SPD beam test D. Elia, R. Santoro INFN Bari ALICE Collaboration - SPD Group

2. D. Elia, INFN BariALICE Offline Week - June 20042 SPD beam test in 2003 (I) Table MWPC Quartz Scintillators Mini bus 0 Pb-Target Table: 150 cm beam Mini bus 1 Middle plane Half stave  158 A GeV/c In beam (10 4 ions/spill, 15 days) 4 mm thick Pb target  3 days with 120 GeV/c proton/pion beam

3. D. Elia, INFN BariALICE Offline Week - June 20043  Target: 4 mm Pb  Trigger: quartz counter (beam) + 2 cm x 2 cm scintillator (interactions)  Mini bus 0, 1: 2 single chips/mini bus mounted in crossed way  Middle plane: single chip under study  Half-stave: read out through MCM including optical module  2.8 GB of data collected Half-stave Target Mini bus 0 Mini bus 1 Middle plane SPD beam test in 2003 (II)

4. D. Elia, INFN BariALICE Offline Week - June 20044 SPD beam test in 2003 (III)  Used for this analysis: proton/pion beam data (detailed understanding of detector behaviour)

5. D. Elia, INFN BariALICE Offline Week - June 20045 SPD beam test in 2003 (III) Minibus 0 Minibus 1 Test chip  Main studies: - alignments, residuals and resolution - cluster analysis - detection efficiency 425 m 50 m 256 rows 32 columns

6. D. Elia, INFN BariALICE Offline Week - June 20046 SPD beam test in 2003 (III) Minibus 0 Minibus 1 Test chip  Available samples: - focussed and wide beam data - full scan of threshold settings - tilt angle scan (inclined tracks)

7. D. Elia, INFN BariALICE Offline Week - June 20047 Alignments  Fine tuning of the alignment for the test plane: - track prediction residuals centering  Alignment of the minibuses and track reconstruction  rms(x) = 117  m (y) = 14.9  m All cluster tupes:

8. D. Elia, INFN BariALICE Offline Week - June 20048 Residuals and resolution (I) Single pixel-clusters: rms(x) = 121  m (y) = 14.9  m (x) = 12.6  m (y) = 13.6  m Double-pixel clusters:

9. D. Elia, INFN BariALICE Offline Week - June 20049 Residuals and resolution (II) Residuals for single pixel clusters: rms(x) = 121  m (y) = 14.9  m Spatial precision of the telescope (simulation):  telescope  10 m  pixel (x) = 121 m  pixel (y) = 11 m @ VTH = 200

10. D. Elia, INFN BariALICE Offline Week - June 200410 Impacts vs cluster size Single-pixel cluster Double-x-pixel cluster Double-y-pixel cluster

11. D. Elia, INFN BariALICE Offline Week - June 200411 X-impacts vs cluster size Single-pixel cluster @ VTH = 200 Double-x-pixel cluster

12. D. Elia, INFN BariALICE Offline Week - June 200412 X-impacts vs cluster size @ VTH = 200  = 15 m

13. D. Elia, INFN BariALICE Offline Week - June 200413 Y-impacts vs cluster size Single-pixel cluster Double-y-pixel cluster

14. D. Elia, INFN BariALICE Offline Week - June 200414 Residuals vs threshold (I) @ VTH=80 (y) = 16.6 m @ VTH=120 (y) = 17.9 m @ VTH=200 (y) = 14.9 m @ VTH=214 (y) = 13.8 m Single-pixel clusters

15. D. Elia, INFN BariALICE Offline Week - June 200415 Residuals vs threshold (II) Double-y-pixel clusters @ VTH=80 (y) = 21.0 m @ VTH=120 (y) = 14.1 m @ VTH=200 (y) = 13.6 m @ VTH=214 (y) = 15.8 m

16. D. Elia, INFN BariALICE Offline Week - June 200416 Cluster type studies (I) 13245 7 6 9 10 8 12 11 13 Following classification implemented: 14 = all other types

17. D. Elia, INFN BariALICE Offline Week - June 200417 Cluster type studies (II) 13245 7 8 VTH = 200

18. D. Elia, INFN BariALICE Offline Week - June 200418 Cluster type studies (III) 13245 7 8 9 10

19. D. Elia, INFN BariALICE Offline Week - June 200419 Cluster type studies (III) 6 11 12 13

20. D. Elia, INFN BariALICE Offline Week - June 200420 Cluster type studies (IV) VTH=214 VTH=200

21. D. Elia, INFN BariALICE Offline Week - June 200421 Cluster type studies (V) 13245 7 8 VTH = 214

22. D. Elia, INFN BariALICE Offline Week - June 200422 Cluster type studies (VI) VTH=200 VTH=180

23. D. Elia, INFN BariALICE Offline Week - June 200423 Cluster type studies (VII) VTH=140 VTH=120

24. D. Elia, INFN BariALICE Offline Week - June 200424 Cluster size vs threshold (I) @ VTH=214 @ VTH=200 @ VTH=160 @ VTH=90

25. D. Elia, INFN BariALICE Offline Week - June 200425 Cluster size vs threshold (II)

26. D. Elia, INFN BariALICE Offline Week - June 200426 Efficiency study  Event selection: - 1 cluster on each of the tracking planes - track crossing the test plane (acceptance limits)  @ VTH>150: - efficiency  99.9%  Threshold scan study: