1. Stack to Stack connection Jun/2003@CERN O.Sato

2. Motivation Emulsion coordinate aligned to TT coordinate by Komatsu :: CTransEmulToTT(*); Emulsion tracks on the “Absolute coordinate”. Track slope in 1mrad Track position in 100 micorn Then Stack to Stack conection should be possible !! Without alignment procedure which is heavy job up to Now. Physics tau to electron channel can be analysed !!!

3. Stack to Stack distance 7.6cm21.9cm 7.6cm Beam

4. Sample to be checked All penetrating tracks in all NETSCAN evsnts in a half module [area 36 cm x 36 cm ] of Stack[i] and Stack[i+1]. Then try to connect Stack[i] and Stack[i+1]. Remakr: Tracks sample is mainly beam muons slope in center (0.0, 0.043).

5. 8pl 50 tracks /box 7.6cm or 21.9cm Beam

6. Stack 3 to Stack4 connection Mean =140 Sigma=232 micron Mean = -203 Sigma= 202 micron Mean = -0.6 Sigma= 3.4 mrad Mean =0.7 Sigma=3.7 mrad Position residual Angle residual Selection Dy x Dz < 1500 x 1500 micron 2 Dth= 10 mrad Selection Dspace <1000 micron Day x Daz < 15 x 15mrad 2

7. Table of residuals Remak scattering error also including

8. Intrinsic position resolution Changing angle allowance 5mrad to 2mrad Looking position residual sigma Stack 1 to 2 (3 to 4) Sigma 120 micron Satack 2 to 3 Sigma 250micron About 1 mrad pointing accuracy by netscan track @infinit momentum case

9. Rough estimation on connection efficiency Effective scanning NETSCAN area in next stack are estimated. Depending on module but roughly (3. to 5 %) of next stack module surface So connection efficiency can be calculated. And comes out as at least 75%. (At least mean no fiducial volume correction who will reduce effective scanning area etc.)

10. Summary Now tracks reconstructed by NETSCAN is on the “Absolute Coordinate”. Position Alignment TT and Emulsion is well bellow 100 micron in position. Stack to Stack connection become easy ! Remaining residual come from NETSCAN angular resolution about 1mrad by 8 plates Prediction accuracy stack to stack is 90 micron + (delta theta by scattering) x 7.6cm 230 micron + (delta theta by scattering) x 21.9cm Connection efficiency comes out as at least 75 %.

11. Things should be done This study is done by existing data sets, So mainly beam muons are used and angular distributions was limited due to requesting 8plate passing through. And scanning area is limited as several %, almost all track is not scanned in next stack in present DATA sets. So… Connection efficiency estimation Tracks from located events especially muons. Angle dependence But there is no difference to connect next plates except resolution … so the connection efficiency should be close to 100 %. BG connection estimation (negligible if not in beam center).