1. Track ranking in CS analysis T. Fukuda 20/Jan ‘09 OPERA–JAPAN (Mizunami) meeting

2. Aim Saving manual check load in CS analysis by picking up only track whose quality is like real track.

3. Track ranking After preparing 4/4 and ¾ track, we evaluate track quality.  Track ranking 4/4 3/4 VPH x 4surface (VPH is darkness of track), Delta-angle(base-micro) x 4surface x 2projection, Delta-angle(base1-base2) x 2projection  total 14 parameter @4/4track (total 9 parameter @3/4track)  calculation of chi-square probability CS2 CS1

4. VPH distribution This sample is CS track already found during 08’July-08’October. Investigated VPH distribution of micro track every 100mrad. VPH (0.0rad-0.1rad) VPH (0.1rad-0.2rad) VPH (0.2rad-0.3rad) VPH (0.3rad-0.4rad) VPH (0.4rad-0.5rad) VPH (0.5rad- )

5. Delta-angle(base-micro) Sample track is same on the case of PH. Investigated delta-angle between Base track and Micro track each angle and each ph (angle:every 150mrad, ph:6-8,9-12,13-16), dAx (0.0rad-0.15rad,PH13-16) dAx (0.0rad-0.15rad,PH9-12) dAx (0.0rad-0.15rad,PH6-8) dAx (0.15rad-0.3rad,PH13-16) dAx (0.15rad-0.3rad,PH9-12) dAx (0.15rad-0.3rad,PH6-8) Sigma=22mrad Sigma=15mradSigma=18mrad Sigma=27mradSigma=30mrad (0.3rad-0.45rad) :Sigma = 35mrad(PH13-16), Sigma = 40mrad(PH9-12), Sigma = 47mrad(PH6-8), (0.45rad-0.6rad) :Sigma = 55mrad(PH13-16), Sigma = 61mrad(PH9-12), Sigma = 70mrad(PH6-8)

6. Delta-angle (base1-base2) dAy (0.0rad-0.1rad) dAy (0.2rad-0.3rad)dAy (0.4rad-0.5rad) dAy (0.1rad-0.2rad)dAy (0.3rad-0.4rad)dAy (0.5rad-) Sample track is same. Investigated delta-angle between Base track(CS1) and Base track (CS2) every 100mrad. This parameter is applied in the case of 4/4 track. Sigma=5mrad Sigma=6mrad Sigma=8mrad Sigma=9mrad Sigma=8mrad

7. Chi-square distribution ABCD E Track ranking is used Chi-square probability. VPH distribution is not gauss distribution. So, distribution converted to gaussian for applying chi-square technique. Chi-square like distribution of found real track Quality Level A: 0.0 – 0.9 (33%) B: 0.9 – 1.4 (34%) C: 1.4 – 2.0 (20%) D: 2.0 – 3.0 ( 9%) E: 3.0 – (4%) Plot is chi-square like distribution using 14 parameter (4/4 track). Left one is real track, Right one is fake track. I give quality level (A-E) to each track. AB C DE Chi-square like distribution of typical fake track 4/4 track Xray alignment +- 50micron 120cm 2, <0.7rad

8. CS - Manual check Now we are applying track ranking to all CS-Manual check. We check manually as following procedure. 1. I check compton alignment map and judge to use or not. 2. I control number of tracks should be checked. [Normal case] CC event : 4/4track top10-top20, and muon hunting (3/4, 4/4) NC event : 4/4track top10-top20, and 3/4track top10 Compton Alignment success 227471534\9197212 237862770\15109010 Compton Alignment partly success  Miyamoto

9. This is CS analysis result sheet. Each Track ranking is given automatically. Recent result of manual check. ( 401trks in 29events ) ABCDE Real trk 70553391 Fake trk 119519864 After manual check, Found track – TT hit matching Event validation Brick request Decision of location method (SBL/DVh)

10. Summary I’m developing Track Ranking method for effective manual check. Now in CS analysis @Nagoya, basically this method is applying for all CS-manual check. The number of tracks should be manual checked is 10-30tracks. Next step Improvement of weight considered to S/N. Investigation of possibility of automatic track selection (no manual check ! )  CS team people start to Decay Search !

12. Chi-square distribution ABCD E Track ranking is used Chi-square probability. VPH distribution is not gauss distribution. So, distribution converted to gaussian for applying chi-square technique. - procedure of conversion, for example, (0.0rad-0.1rad) : [VPH:35-39]  [65-70%  67.5%]  [0.98sigma] (0.0rad-0.1rad) : [VPH:56-60]  [35-40%  37.5%]  [0.49sigma] Chi-square like distribution of found real track Quality Level A: 0.0 – 0.9 (33%) B: 0.9 – 1.4 (34%) C: 1.4 – 2.0 (20%) D: 2.0 – 3.0 ( 9%) E: 3.0 – (4%) Plot is chi-square like distribution using 14 parameter (4/4 track). Left one is real track, Right one is fake track. I give quality level (A-E) to each track. AB C DE Chi-square like distribution of typical fake track 4/4 track Xray alignment +- 50micron 120cm 2, <0.7rad