CS Edge part Distortion analysis

2006-12-08

T.Yoshioka

M.Kazuyama

Edge

Emulsion

about 50 μm

the Edge

Distortion

2nd surf (lens side)

base

1st surf (stage side)

micro track

micro track

base track

distortion vector

• Distortion is expressed the angle difference between micro track and base track

Distortion Analysis

• Samples– CS(double refreshed) 　 exposed pion 10GeV

• Condition– Temp. 25 ℃ Humi.40-45%

• Scan– UTS and Manual Checking

sample1 Edge

(0,0)

scan area

1cm

1cm

Edge

X or Y coordinates vs absolute value of distortion

Maximum value of distortion is about 220mrad at 120μm of distances from the edge.

sample1

Edge

(0,0)

scan area

1.2cm

1cm

Maximum value of distortion is about 300mrad at 80μm of distances from the edge.

Edge

X or Y coordinates vs absolute value of distortion

sample2

(0,0)

8mm

6mm

scan area

Edge

X or Y coordinates vs absolute value of distortion

Maximum value of distortion is about 120mrad at 180μm of distances from the edge.

sample2

(0,0)

8mm

6mm

scan area

Edge

X or Y coordinates vs absolute value of distortion

Maximum value of distortion is about 130mrad at 90μm of distances from the edge.

Result

• Manual Check can find tracks about 300 mrad distortions at 80μm from the edge.

• UTS can scan up to 200μm position from the edge.

Musiburo(Steam bath)

1.Rise Temp to 30-40 ℃ and Humi to 95%.2.Keep high Temp and Humi for 24 hours.3.Lower Temp and Humi slowly

Ariga’s Master Thesis

Before

(0,0)

scan area

After

(0,0)

scan area

Before

(0,0)

scan area

AfterDistortion has reduced !!

(0,0)

scan area

Summary

• We can find a track at least 200μm from the edge . Probably we will be able to reach up to 100μm .

• Musiburo is very effective way for reducing distortion.

• A difference of 2 samples are now researching.