1. Cristiano Bozza – European Emulsion Scanning Group – Nagoya Jan 2008 1 OPERA brick scanning by the European Scanning System

2. Cristiano Bozza – European Emulsion Scanning Group – Nagoya Jan 2008 2 Basic concepts DB is used as the backbone for operations Not only book-keeping but living memory and working tool Data immediately ready for publication Scanback-scanforth-followdown procedures Can use base-tracks and/or microtracks TotalScan can use volumes of any shape Continuous data quality monitoring 20 cm 2 /h/side/stage Optical/X-ray marks 1-zone/3-zone/no intercalibration by tracks

3. Cristiano Bozza – European Emulsion Scanning Group – Nagoya Jan 2008 3 Scanback-scanforth-followdown Candidates are propagated with last position/slope (position only if microtracks - tunable) Candidate selection based on: 1) slope agreement 2) track quality + tolerance cuts 3) combined slope+position agreement Forking (multiple candidates) supported but not yet used (relevant only on first plate)

4. Cristiano Bozza – European Emulsion Scanning Group – Nagoya Jan 2008 4 Scanback-scanforth-followdown 4 micron 2 mrad Typical performances using local intercalibration Fill factor in the range 85%÷100% (base tracks) or 97%÷100% (  tracks) Stopping point is reliable

5. Cristiano Bozza – European Emulsion Scanning Group – Nagoya Jan 2008 5 Scanback-scanforth-followdown Coming soon: Plate skipping to speed up search Switching from Optical to Lateral X-ray and vice-versa (for plates with damaged grid or X-ray marks)

6. Cristiano Bozza – European Emulsion Scanning Group – Nagoya Jan 2008 6 TotalScan (Volume scan) Continuous data quality monitoring Base track density is a good quality estimator However, all microtracks are saved to the DB Data are already aligned (within 20  m) if calibrated optical marks or lateral X-ray marks are used Full reprocessing is available using DB data, as deeply as with raw data files The logical association between a volume and the stopping point is saved and documented in the DB (no need to “guess”)

7. Cristiano Bozza – European Emulsion Scanning Group – Nagoya Jan 2008 7 Vertex confirmation with TotalScan data At least two volume scan data sets available: 1) Intercalibration data around scanback path (4÷6 mm linear size) Hard cuts to improve purity for intercalibration Alignment and vertex reconstruction available few seconds after end of scanback SB (red) + Intercal data (rainbow) 2) Volume scanning around confirmed stopping point (1 cm 2 at least) Record all microtracks, focus on efficiency Usually needs 1÷2 hours’ scanning Complete emulsion reconstruction possible with full dataset

8. Cristiano Bozza – European Emulsion Scanning Group – Nagoya Jan 2008 8 Data quality with TotalScan data Track precision is 0.9  m already in preliminary reconstructions (vertex confirmation), inclusive of scattering effects  y fit-measure (  m) Fill factor of volume tracks using microtracks is 91%÷100% Vertex and decay search included (re-analysis is obviously possible) Follow-down obtained “for free” in many cases

9. Cristiano Bozza – European Emulsion Scanning Group – Nagoya Jan 2008 9 3 micron Intercalibration details Track maps used to intercalibrate brick plates together 3 zone scheme Overall alignment 8×8 mm 2 /zone Y alignment residuals (  m) vs. X (  m), plate by plate 1 zone scheme Local alignment following track 6×6 mm 2 plate X (  m)

10. Cristiano Bozza – European Emulsion Scanning Group – Nagoya Jan 2008 10 Intercalibration details Fixed reference on single plate obtained by Optical Marks or Lateral X-ray Working and used in several labs as an alternative to speed up scanning The ESS can switch from each method to the other Automatic intercalibration by Lateral X-ray marks Scanback following residuals Red and black: 2 different bricks

11. Cristiano Bozza – European Emulsion Scanning Group – Nagoya Jan 2008 11 Efficiency improvement Fill factor of base tracks higher in SB (91%) than in TS (84%) Working group investigating First results: efficiency related to number of trials in scanning (tracks in overlapping areas have higher probability of being taken) Work going on, checks on optical effects coming soon

12. Cristiano Bozza – European Emulsion Scanning Group – Nagoya Jan 2008 12 Efficiency/precision improvement Working group developing Z-synchronized data taking Prototype SW expected in next weeks Z Camera Improved Z determination should increase base track precision and efficiency, possibly microtrack efficiency and precision too

13. Cristiano Bozza – European Emulsion Scanning Group – Nagoya Jan 2008 13 Conclusions European Scanning System is already producing complete emulsion data sets (vertex location + study) Data quality good, physics reconstructions in emulsion also attempted Data already available in Central DB for analysis and algorithm testing System still evolving, efficiency/precision improvements going on (+ more to be shown during Emulsion Workshop)