1. Development of automatic tracking particle of X to detect Double Hypernuclei (E07 in J-PARC)
Kaori Umehara, Saeka Hataguchi,
Asuka Fukunaga, Daisuke Yuzawa,
Sayuri Niwa, Kaoru Hoshino, Kazuma Nakazawa
Physics department of Gifu University, Japan

2. Status of X particle scanning system
Plate of a section
Up gel
Base
Down gel
Upstream plate
Downstream plate
track
500mm
40mm
SCIFI-Block
Diamond (12C) target
SCIFI-Bundle
Emulsion stack X-
LLZ LZ
1.67GeV/c K- p- K+
layered image of upstream and downstream
Upstream track
Downstream track
E373 setup
Move position of Ξ- particle to be followed
Recognition of followed track
Need human help
Following track
E07 is 10 times track of E373
→need high speed
→automatic
17±9.2mm by alignment with gridmark position

3. 1. Judgment of emulsion surface
Full automated scanning system
1. Judgment of emulsion surface
Take image
(brightness average of 9×9pixel)－(brightness center of 9×9pixel)　
Sum of absolute value
Judgment of up gel, base and down gel
In gel
→grain is black
→different brightness of circumference of grain
Sum
×104
Relation between sum and z direction z

4. 1. Judgment of emulsion surface
|(brightness average of 9×9pixel)－(brightness center of 9×9pixel)|
　　　　　＞　brightness threshold　→　1
　　　　　＜　brightness threshold　→　0
sum after binarization value　→　Judgment of up gel, base and down gel
Sum
×104
Sum
×104
revision
Compression that min become min after binarization z z
|(brightness average)－(brightness center)| 　 　Binarization(brightness threshold 4)

5. 2. Alignment with beams’ position
Plate of a section
track
Take layered image
Filtering
Binarization
Get outline of beams
Pattern matching
Up gel
Base
Down gel
Upstream plate
Downstream plate
Up gel
Base
Down gel
Take layered image in 2mm gap
Image
after filtering
Image after binarization
Image of outline of beams

6. 2. Alignment with beams’ position
Consistency of beam position
(correspondence points inside circle)
Take layered image
Filtering
Binarization
Get outline of beams
Pattern matching
Upstream plate
Downstream plate
Image before alignment
Upstream track
Downstream track
Image after alignment
After check of consistency
Position accuracy is obtained as 1.2±0.2mm.

7. 3. Recognition of followed track
Up gel
base
Down gel
Upstream plate
Downstream plate
track
Take track angle in the emulsion
Take layered image
Rotate the image
Extract necessary part
Take data position and angle
Plate of a section
Take position (x,y) and angle. x
Taken angle
Upstream plate
Downstream plate

8. Part of 15mm length of the emulsion surface was not seen.z
track q
Upstream plate
Downstream plate
Layered image
gap
Up gel
Base
Down gel
Plate of a section
Part of 15mm length of the emulsion surface was not seen.

9. 4. Following track Take track angle in emulsion
Predict track from position, z gap and angle
Move predicted track
Recognition of track
Take date position and angle
Up gel
Base
Down gel
Plate of a section
track
No recognition
→think to be Xstop
→follow track short gap of z
→take image round Xstop

10. Summary Flow of fully automated scanning system
Judgment of emulsion surface (up gel)
Take beams’ position and brightness(Particle identification)
Alignment with beams’ position
Recognition of followed track
Following track
Judgment of emulsion surface (base)
Following track+ Judgment of emulsion surface (down gel)
Up gel
Base
Down gel
Plate of a section
E373 detected about 5 years → E07 about 50 years
If we scan for 1 year
　・1day　20hours
　　1year　20[hours]×365[days]=7300[hours]
　　　　　≈2.6×107[s]
　・time to scan 1 track/plate
2.6×107[s]/(1.8×103[track]×110[mod]×6[plate])
　　≈20[s/event]

11. Summary
Judgment of emulsion surface is done by summing up binarized value.
Alignment with beams’ position, recognition of followed track, and following track are done off line.
Relation between gap and tanq was found.
To drive the system on-line, the program is built in computer which controls the microscope.

12. Back　up

13. 差=(emulsion内のmin)－(min)
表面認識(輝度閾値) 合計
×104
Emulsion内のmin
差=(emulsion内のmin)－(min) 差 z
min
輝度閾値

14. 表面認識

15. 表面認識(二値化) (9×9pixelの平均)－(9×9pixelの中心の輝度)の絶対値 ＞ 輝度閾値 → 1 ＜ 輝度閾値 → 0
　　　　　＞　輝度閾値　→　1
　　　　　＜　輝度閾値　→　0
二値化した値の合計
dB=(in　emulsion)-(out　emulsion)
dB(二値化)/dB(輝度差) ≈2 合計
×104 合計
×104 補正
Minが同じになるように圧縮する
Sum=0.051z2+48z+79000
Sum=0.059z2+43z+56000 z z
平均－輝度の絶対値　　　　　　　　　　　　　　　　二値化(輝度閾値4)

16. フィルター処理後
の画像
6×6フィルター

17. パターンマッチ
上流側
下流側 中点 up
down θ
上流で引いた直線と下流で引いた直線の中点を合わせ、中点周りに下流の点を回転

18. Relation remainder between remainder and brightness threshold
Up gel
Base
Down gel
Plate of a section z
Relation remainder between remainder and brightness threshold
remainder
×103
Remainder
=(min in emulsion)－(min)
Brightness threshold

19. Emulsionの削れ
上流plate
下流plate z
track q
gap

20. Up gel
Base
Down gel
Plate of a section
50mm
track

21. 4. Following track 角度を取得 重心と角度の情報から、Trackの位置を予測 予測された位置へ移動
→Xstopがあると考える
→stopがあると考える間を細かく見る
→stop点まわりの画像を取得
Up gel
Base
Down gel
Plate of a section
track