Scanning status in Europe Giovanni De Lellis University of Naples

Scanning strategy General scan on the first 2 emulsion sheets Match the emulsion doublets with the SFT Scan-back all the matched tracks up to the vertex (majority are passing through also on wall 1 since there was no veto plane) Volume scan around the stopping plate to detect vertexes Second approach: scan all emulsion sheets, find the vertexes (unbiased) and require the SFT matching only at the end

 z correction position accuracy σ tx  7 mrad σ ty  10 mrad σ y  566 µm σ x  474 µm RMS vs ΔZ ΔZΔZ SFT matching for brick 88 (Bologna)

SFT matching for brick 92 (Bern) and brick 82 (Salerno)

SFT matching for brick 46 (Naples) s =540 micron s =400 micron s =9 mrad s =6 mrad

Scan-Back of brick emulsion doublets matching with the SFT have been scanned back 70µm in position and 30mrad in angle as tolerances 136 stopping point have been detected A classification of the events done by checking all the 326 tracks with the SFT Viewer: 25 promising events 5 probably promising events 38 unclear (crowded) events The remaining ones are passing through tracks example of interesting events For the 136 stopping points a volume scan was performed 11 plates in total (±5) 5x 5 mm 2 on each plate 50% of the plates scanned so far

235 tracks selected from the SFT matching 100µm in position and 40mrad in angle as tolerances (dry objective lens) 125 stopping points out of the 235 Volume scanning is performed along 9 plates (± 4 plates), 5x5 mm2 skewed zones Scan-Back of brick prong events 7 2-prong events 2 back-scattering The remaining ones are mostly passing through

Brick number Brick wall Lab Exposure days Cosmic rays (h) SFT align ment SFT trigger Emulsion-SFT position offset (resolution) μm Emulsion-SFT angular offset (resolution) mrad Scanning modeIn progress BL0892Bari2812OK3-D tracks5310 (792), 3359 (735)3 (17), 5 (15)predictiontotal scan BL0422Bari212not yetgeneral 37cm 2 for 3 platesSFT alignment BL0912Bari2812not yetgeneral 26cm 2 for 3 platesSFT alignment BL0922Bern3012OK BL0341Bologna182OK9/20 planes9072 (770), 1755 (890)6 (8), 6 (9)general 80cm 2 for 26 platesgeneral scan BL0442Bologna212OKgeneral 30cm 2 for 57 plates BL0882Bologna2812OK9/20 planes10564 (474), 3456 (566)10 (7), 10 (10) general 80cm 2 for 23 plates; scan-back from triplets (250) total scan Lyon BL0452LNGS202not yet general: 16cm 2 for 3 plates; 80cm 2 for 2 plates; 16cm 2 for 3 plates with new filter SFT alignment BL0563LNGS2112not yetgeneral 16cm 2 for 2 platesSFT alignment BL0331Naples182OK9/20 planes (605), (443)-24. (5.), -3. (8.) general 48cm 2 for 43 plates and 24cm 2 for 57 plates general BL0462Naples182OK7/20 planes-6830 (430), (430)-3. (6.), -3. (8.)general 100cm 2 for 3 plates BL0543Naples2112not yet general 9cm 2 for 7 plates (efficiency) BL0432Neuchatel212not yet general 16cm 2 for 18 plates scan-back from 3 first plates volume scan - SFT alignement BL0811Salerno3612OK3D Tracks-6164 (491), (482)-7. (7.), -7. (7.)General on 2 plates BL0821Salerno3612OK3D Tracks-4237 (490), (484)-8. (7.), -13. (7.)General on 2 plates BL0472Salerno212OK3D Tracks-5700 (745), (465)-12. (5.), -9. (4.)General on 2 plates

Conclusion 17 bricks under analysis in Europe (about 1000 events expected) Emulsion to SFT alignment performed for the majority of them The scan-back has been performed in a few bricks only Different criteria have been used: SFT triggers, SFT- emulsion matching and volume around the stopping point to be scanned (skewed, how many, etc..) Unification of all the cuts is ongoing: trigger conditions, SFT matching criteria and volume scanning standardized After a quick revision of the analysis, it will be possible to merge all the data