Basic characteristic o f 100 μ mGEM K,Kadomatsu ( saga.u) 池池池池 池池池池池 、、 池池池池 池池池池池 池池池池池池 、、、 池池池池 池池池池池 池池池 池池 池池池池 、、一、( KEK) 池池池池 池池池池 池池池池 、() 池池池 池池池池池 池池池池池 一、() 池池池池 池池池池池池 ()
Basic characteristic of100 μ mGEM
K,Kadomatsu ( saga.u)
池野正弘、宇野彰二、内田智久、氏家宣彦、関本美智子、田中秀治、田中真伸、仲吉一男、村上武( KEK)
青座篤史、杉山晃(佐賀大)中野英一、中川伸介(大阪市大)
杉山史憲(東京理科大)
Motivation
• To understand a basic characteristic of 100 mGEM.
• We inspect that 100 mGEM can provide higher gain than 50 mGEM.
We want to get high gain
GEM Foil
140 μm
φ = 70μm
50 μm
5 μm
5 μm
CuPolyimide
10cm
10cm
Scienergy Co., Ltd. 製100μm
8 μm
8 μm
CuPolyimide
100m-GEM1
Drift Plate
2 mm
ED=0.75kv/cmEI=7kv/cm
Single 100mm-GEM Test Chamber
2 mm
Drift Area→ED
Induction Area →EI
GASAr-CO2(70/30)
2200pF
2200pF
Read out
Read out
55Fe (5.9 keV X-ray)
PCB
1mm
□15mm×15mm
36 = 6×6
PCB
10
100
1000
10000
250 275 300 325 350 375 400
Δ Vgem/ 2 (100μ ) = Δ Vgem 50μ [V]( )
Gain
100μ (single)m
50μ (triple)m
We normalize ΔVGEM of 100μmGEM to Δ VGEM of 50μmGEM
Higher Gain is obtained with 100μmGEM
もう少し、高い電圧を掛けれるようにしたい
Single GEM Δ VGEM
Single GEMED dependence
0
0.2
0.4
0.6
0.8
1
1.2
0 0.05 0.1 0.15 0.2 0.25
Field Ratio (ED/ Ehole)
Collection Effi
ciency 100μ GEM
50μ GEMΔVGEM=660VEI=6.0kV/cmEhole=61.9kV/cm
ΔVGEM=660VEI=6.0kV/cmEhole=61.9kV/cm
100mGEM
ΔVGEM=350VEI=7.0kV/cmEhole=47.5kV/cm
ΔVGEM=350VEI=7.0kV/cmEhole=47.5kV/cm
50mGEM
・ ・・
・
Single GEM EI dependence
00.20.40.60.81
1.21.41.61.8
0 0.05 0.1 0.15 0.2 0.25
Field Ratio (EI/ Ehole)
Extraction Effi
ciency
100μ mGEM50μ mGEM
ΔVGEM=660VED=0.76kV/cmEhole=61.9kV/cm
ΔVGEM=660VED=0.76kV/cmEhole=61.9kV/cm
100mGEM
ΔVGEM=350VED=0.5kV/cmEhole=47.5kV/cm
ΔVGEM=350VED=0.5kV/cmEhole=47.5kV/cm
50mGEM
・ ・・
00.20.40.60.81
1.21.41.61.82
0 1 2 3 4 5 6 7 8 9 10 11 12 13
Electric field (kV/ cm)
Relative Gain
EI dependence High Electric field
ED=0.75kV/cm
ΔVGEM=640V
ED=0.75kV/cm
ΔVGEM=640V
ED=0.75kV/cm
ΔVGEM=620V
ED=0.75kV/cm
ΔVGEM=620V
ED=0.75kV/cm
ΔVGEM=660V
ED=0.75kV/cm
ΔVGEM=660V
Double GEM Test Chamber
2.0 mm
2.0 mm
2.0 mm
Induction
Drift
Transfer
7.0kV/cm
0.75kV/cm
ET
Double GEM, 100μm ET dependence
0
0.2
0.4
0.6
0.8
1
1.2
0 0.5 1 1.5 2 2.5 3Et[kV/ cm]
Relative Gain
ArCO2
0
0.2
0.4
0.6
0.8
1
1.2
0 0.5 1 1.5 2 2.5 3
ΔVGEM=500VED=0.75kV/cmEI=7.0kV/cm
ΔVGEM=500VED=0.75kV/cmEI=7.0kV/cm
Double GEMΔV GEM
100
1000
10000
100000
380 430 480 530 580
Δ VGEM[V/ cm]
Gain
P10
P10[ ]抵抗あり
Ar-CO2(70-30)
Ar-CO2(70-30)[ ]抵抗あり
We were not able to apply the high voltage to ΔVGEM
高 Gain を得たい
Now
• Electric field @ Hole center– 100 μ mGEM:61.9 kV/cm (Maxwell 3
D)– 50 μ mGEM:47.5 kV/cm (Maxwell 3D)
• Single GEM Max high Voltage→Δ VGEM:660V
• Double GEM Max high Voltage→ Δ VGEM:540V – It is easy to discharge in Double GEM.
• The second layer GEM discharges due to large number of electrons produced at the First layer GEM
We change a diameter of GEM hole.
70μ m φ→ 90 μ m φ
100μGEM ( 90φ )
Drift Plate ( Mesh )
2mm
2mm
Single GEM Δ VGEM
10
100
1000
10000
500 550 600 650 700 750 800
Δ Vgem[V]
Gain
90φ70φ
ED=1.5kV/cmEI=6.0kV/cmEhole=61.9kV/cm
ED=1.5kV/cmEI=6.0kV/cmEhole=61.9kV/cm
70Φ
ED=1.5kV/cmEI=6.0kV/cmEhole=58.0kV/cm
ED=1.5kV/cmEI=6.0kV/cmEhole=58.0kV/cm
90Φ
0
0.2
0.4
0.6
0.8
1
1.2
0 0.02 0.04 0.06 0.08 0.1
Field Ratio (ED/ Ehole)
Collection Effi
ciency
70Φ90Φ
ED dependence90Φ VS 70Φ
ΔVGEM=660VEI=6.0kV/cmEhole=61.9kV/cm
ΔVGEM=660VEI=6.0kV/cmEhole=61.9kV/cm
70Φ
ΔVGEM=660VEI=6.0kV/cmEhole=58.0kV/cm
ΔVGEM=660VEI=6.0kV/cmEhole=58.0kV/cm
90Φ
0
0.2
0.4
0.6
0.8
1
1.2
1.4
0 0.05 0.1 0.15 0.2
Field Ratio (EI/ Ehole)
Extraction Effi
ciency
70Φ90Φ
EI dependence90Φ VS 70Φ
ΔVGEM=660VED=0.76kV/cmEhole=61.9kV/cm
ΔVGEM=660VED=0.76kV/cmEhole=61.9kV/cm
70Φ
ΔVGEM=660VED=0.76kV/cmEhole=58.0kV/cm
ΔVGEM=660VED=0.76kV/cmEhole=58.0kV/cm
90Φ
Summary• 100μmGEM
– We have measured the basic characteristic.• A Higher Gain can be got with 100 m-Single GEM than t
hat with 50 m-Double GEM . But the gain is not so high as that with 50 m-Triple GEM
– A diameter of a GEM hole.• We changed a diameter of a GEM hole to 90μm φ from 70
μm φ– We can apply higher ΔVGEM .– We can get 2times larger gain.
• Electric field @ Hole center– 70 μ m φ :61.9 kV/cm– 90 μ m φ :58.0 kV/cm
Recycle GEM
• We try to revitalize the GEM which discharges.
Dead GEM
Normal
Damaged
There is burnt area
Zoom
Soft etching1~3%の塩酸水溶液に浸ける
50cm /分のスピードでエッジングされる
エッジングマシン
80℃で6時間 乾燥
東海電子工業株式会社の方でエッジングを行った。
Reprocessing
• Soft etching– Etching time is shorter than usual chemical etching.
• Plasma etching– An etching effect is stronger than chemical etching.– Dead GEMs, which can not be recovered by soft etchin
g , are regenerated by Plasma etching.
Recovery of GEM is basically possible
About 90% of Dead GEMs can be recovered by Soft or Plasma etching .
10000
1000
100
10
250 300 350 400 450 500 550 600 650 700 750
ΔVgem
こちらを見てください
0.6
0.7
0.8
0.9
1
1.1
1.2
0 0.5 1 1.5 2 2.5 3 3.5 4
Ed[kV/ cm]
Relative Gain
90φ70φ
ΔVgem=660VEi=6.0kv/cm
ED dependence90Φ VS 70Φ
0
0.2
0.4
0.6
0.8
1
1.2
1.4
0 1 2 3 4 5 6 7 8 9 10
Ei[kV/ cm]
Relative Gain
90φ70φ
Ed=1.5kv/cmΔVgem=660V
EI dependence90Φ ,V,S 70Φ
0
0.2
0.4
0.6
0.8
1
1.2
0 0.02 0.04 0.06 0.08 0.1
Field Ratio (ED/ Ehole)
Collection Effi
ciency
100μ GEM50μ GEM
ED
ΔVGEM=660VEI=6.0kV/cmEhole=61.9kV/cm
ΔVGEM=660VEI=6.0kV/cmEhole=61.9kV/cm
100mGEM
ΔVGEM=350VEI=7.0kV/cmEhole=47.5kV/cm
ΔVGEM=350VEI=7.0kV/cmEhole=47.5kV/cm
50mGEM
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
0 0.05 0.1 0.15 0.2 0.25
100μ mGEM50μ mGEM
EI