KOPIO(BNL-E926)???? a??????Nitrogen Scintillation ???

1
KOPIO(BNL-E926)???? a??????Nitrogen
Scintillation ???
???????_at_????????? 2003?2?6?
???????????????????? ?????? ???????????? ?? ??

• Contents

• KOPIO
• ??????????Nitrogen Scintillation
• ????????????
• N2???????????Quenching??
• Beam catcher ????

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KOPIO Measurement

• ??
• Cabibbo-?????????????
• ??????
• ??? and nothing!
• ??????
• ??? Back Ground
• Branching Ratio
• ????????Veto ?????
• Beam Catcher ???
• Type Beam
  Cathcer

Wolfenstein style
prediction
Cabibbo-KOBAYASHI-MASKAWA Matrix
Unitarity Triangle
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KOPIO Measurement

• ???????
• ???????????
• ?????????
• ????????
• CP Violation
• KOPIO????????
• ??????

Unitarity Triangle
Cabibbo-KOBAYASHI-MASKAWA Matrix
4
KOPIO Measurement

• ??
• Cabibbo-?????????????
• ??????
• ??? and nothing!
• ??????
• ??? Back Ground
• Branching Ratio
• ????????Veto ?????
• Beam Catcher ???
• Type Beam
  Cathcer

Wolfenstein style
prediction
Cabibbo-KOBAYASHI-MASKAWA Matrix
Unitarity Triangle
5
Beam Catcher prototype-

• ??????Efficiency
• ??????????
• 1GeV/c ??????
• 0.027p.e.?????????
• Nitrogen Scintillation ????
• ???????
• ???????????

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Machinery and Materials

• Design
• PIN Photo Diode ?Tag
• ???PIN Photo Diode
• ???????
• ?????????
• 2?????????
• ?????
• ??
• ??????

Logics
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Machinery and Materials
kopio N2???
?????
????
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Simulation on Bethe-Bloch formula

• ?? ?????????Estimation
• Bethe-Bloch ?????

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Estimation on max (Energy deposit)

• ??Scintillation ??????Distance ?Estimation
• ?? 4cm ?????
• Energy ???
• Scintillation ??????
• ???????????
• ?????? ????
• ????????????

eV
a-particle in N2
a???
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Experiment -Semiconductor Detector-

• ???????Tag ???Scintillation ????
• ?????200ADC Count ??????
• ?????
• PIN Photo Peak ?Mean ??2s
• PMT2 ?ADC Count gt100
• ??????? ????? PMT1 ?ADC Count gt100
• PMT1 ???????Nitrogen Scintillation
• Distance from Source 7.2mm, 12.2mm, 16.4mm,
  21.6mm, 24.3mm, 31.5mm, 34.5mm

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Experiment -Semiconductor Detector-

• ???????
• ???5.4MeV????
• toy MC ?fitting
• 4cm ????
• Bethe-Bloch?????
• Photoelectron
• ??????????????
• ??????????????
• ????
• ???????????
• Bethe-Bloch ??????

N2
N2
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Geometry Acceptance

• Geometry Acceptance
• a??PIN Photo ???????0.1mm ?????????, ????????.
• ???????????????
• 100,000plot / 0.1mm
• ??????????Photon ??????, Geometry Acceptance
  ???Photon??Estimate ???
• ??????????? q0.2
• Photonphotoelectron/(q A)

Acceptance
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Evaluate on Photon
N2

• Photon / MeV
• ????????Photon ?????
• Mean 154.4 photon
• ?Photon ?
• 5.4MeV
• 154.4 5.4 836 photon
• 940??????836
• 15 ??
• ?????Photon ?
• 28.2 5.4 152 photon

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Quenching effect

• O2 ?N2 scintillation ??????????, ??????
• I0 Quench ?????Photon ?
• I Quench ????
• c O2?
• K 20(??)
• ??? K20 ?, ??????????
• K 22.42.4
• ????????????, ????

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Results and Summary

• Nitrogen Scintillation ?????????
• N2 . 836 photon
• Air . 152 photon
• Quenching ?? K 22.4 2.4 ????????
• Aerogel Cherenkov beam catcher ????
• ??????? 0.027 photoelectron /1Gev/c proton
• Nitrogen Scintillation ????? 0.02 photoelectron
• Factor ??????
• ????????Nitrogen Scintillation ????
• ????????????
• ???????????gas ??

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Discussion
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Discussion
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Discussion