Performance of Compton Alignment in OPERA CS, 2008 run Seigo Miyamoto Jan., 2009, MIZUNAMI.

April, Refreshing OPERA Films Fundamental training to see track with my eyes, treatment,develop emulsion electron shower energy calibration in ECC (10~20GeV) history of my study (The way to establish this technology) The balloon analysis High energy Cosmic rays analysis of atmospheric muon flux I got important data and Idea of MeV electron detection Test experiment and analysis of Compton Alignment momentum calibration in ECC (~1GeV) Development of automatic programs for OPERA CSD Application for Real OPERA CS and quality check CS Manual Check Making Refresh Chamber Making Balloon Chamber and Launching Hardware data analysis

deformation of the films Emulsion film have very good position resolution in the very small area. In 10cm x 10cm position resolution decrease ~20um because the films deform in exposure -> develop -> drying. In the case of CS doublet, bad alignment makes many fake coincidence.

Electron from natural R.I. ~ 1 MeV ~ 100 keV

Deformation Calibration by finding MeV electron peak 10μm Δx from X-ray Alignment

SCAN CS1CS2 SCAN micro track Making base track Compton Alignment base track calibration map Doublet Track Selection (4hold, 3hold, muon selection) Manual Confirm These processes performs fully automatically, which is controlled by Morishima. TT Hit Automation of CS track selection

Automation of getting the deformation map 1. Division of scanning area (5mm x 5mm) 2. Peak search Detection of Compton electrons in the Shift_x,y map for all divided areas 3. Estimation that each alignment is successful or not in each divided areas. 4. Linear interpolation for not successful areas 5. Estimation performance for all areas.

Evaluation performance of Compton Alignment Samples are 425 CSDs scanned in Japan (~early Dec., 2008.) No available alignment in any scanning region 5 (1%) Getting good alignment pattern map (at least 5cm 2, and they are adjoining ), and # of pattern = 1 347(82%) # of pattern is >= 273(17%)

Ratio successful area Samples are 420 CSDs (at least 5cm 2 is available, and including multiple pattern) # of CSD ratio successful is more than 80% is about 360(85%). The Areas couldn’t get available alignments are almost due to large gaps. ~85%

Alignment accuracy Samples are 163 muon track that observed in CSD ( ratio successful is more than 80% ) from beginning to early Dec., Residual from X-ray Alignment 5.5um7.6um

Alignment accuracy Samples are 163 muon track that observed in CSD ( ratio successful is more than 80% ) from beginning to early Dec., Residual from Compton Alignment 2.0um

Summary Compton Alignment is applied for all CSDs full automatically in 2008 RUN. 99% CSD succeed to get alignment at least 5cm 2, and multi pattern is about 17%. CSD - its ratio successful is more than 80% - is about 85%. Alignment accuracy is 2um, BG reduction power is around 1/10.

Future Plan: General MeV electron Detector which has micron position resolution Material Science -Study of Structural Phase Transitions ( Dr. Tanimura (Osaka univ.) presented in Emulsion WorkShop 2008.) Any other ideas ( It’s secret. )