TXePET (Liquid Xe TPC PET)

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TXePET(Liquid Xe TPC PET)

• Aki Maki
• KEK

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PET(Positron Emission Tomography)???
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PET????????????
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Development of PET
TOF-PET TPC-PET Compton Telescope
TXePET
DOI-PET
Crystal-PMT
Small crystal-PSPMT
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PET?????
TXePET????? 0) ????????????? 1)
??????TPC???511keV??????????(????)
DOI???1mm????? 2) ??????????????????????????????(?
?) 3) ????????? ??????????
????????????? ?????????
MRI??????? 4) TOF ???????????? 5)
????????????????? 6) ????????????

• ??????
• ?????
• ?????
• ???PET?????
• 0) ????????????????
• 1) ?????????
• 2) ???????(DOI)?????????
• ????????(???)
• 3) ?????????
• 4) TOF ???????????
• 5) ?????????????????
• 6) ????????????

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(No Transcript)
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For 511 keV ? 33,000 e- 35,000 photons
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PET?????????
?????? Liq. Xe NaITl GSO BGO
LSO LGSO LYSO LaBr3 ??(g/cm3)
3.06 3.67 6.71 7.13
7.4 6.5-7.3 7.25 5.29 ??????(ns) 2,
30 230 30-60 300 42
40-100 41 16 ????(???) 80
100 20-24 10-12 40-80 40-80 80
130 ?????em(nm) 175 415
430 480 420 420 420
380 ???(at ?em) 1.60 1.85 1.85
2.15 1.82 1.82 1.81
1.9 ?????(gray) 103 gt106
102-3 105 ????? ??
?? ?? ?? ?? ?? ?? ??
??? ?? ?? ?? ?? ??
?? ?? ?? ??(C) -111.6 651
1950 1050 2150 2100 2100
783 ??? ?? ?? (100)? ??
?? (100)? ?? ?? ???? - BR
CZ CZ, BR CZ CZ CZ
BR
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Event Building (ASIC/FPGA/PC)
Scintillation (PMT) i. Digitization Base line
subtraction P(ij)?,z,t,E ii. Cluster
search t(ij) t(ij)ltdt ?(ij)
?(ij)ltd? z(ij) z(ij)ltdy iii. Cluster
values E(i)SE(ij) ?(i)SE(ij)?(ij)/SE(ij)
z(i)SE(ij)z(ij)/SE(ij)
r(i)f(?(ij),z(ij),E(ij)) S(i)r,?,z,t,E
Ionization (TPC) 1. Amplification 2.
Digitization Base line subtraction
I(kl)r,z,t,E 3. Cluster search t(kl)
t(kl)ltdt ?(kl) ?(kl)ltd? r(kl)
r(kl)ltdr 4. Cluster values (not z)
E(k)SE(kl) ?(k)SE(kl)?(kl)/SE(kl)
r(k)SE(kl)r(kl)/SE(kl) T(k)r,?, ,t,E
Matching 5. Matching with
S(i)r,?,z,t,E E(i) E(k)ltdE r(i)
r(k)ltdr ?(i) ?(k)ltd? z(k)v(t(k)
t(i)) z(i) z(k)ltdz
T(k)r,?,z,t,E 6. Individual photon
values G(m)r(k),?(k),z(k), t(i),E(i) or
E(k) 7. Pair matching t(m) t(n)ltdt 8.
Event H(a)G(m),G(n)
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Matching between PMT and TPC
v2.2 mm/µsec
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Localization along LOR
Time-of-Flight method Time difference between two
facing PMT clusters
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Interaction of 511 keV photons with Liq. Xenon
Compton scattering 78 Photoelectric
absorption 22 Scintillation
Wph21.6 eV
23,700 photons
?175 nm t2, 40
ns Ionization Wion15.6 eV
32,800 ionization e-
v2.2 µsec/cm Total
attenuation µ0.0951 cm2/g Example
exp-0.0951x9x3.040.074
93 for 9 cm thick
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Photon Angle Compton telescope Interaction
Photon of 511 keV with Liq. Xe 78
Compton scattering 22 Photoelectric
Absorption
Notation In-coming photon energy E1 E2
T3 Scattered photon energy E2 (measured)
angle
? Recoiled electron energy T3 (measured) 3D
coordinates of two interactions
x1, x2
(measured) Electron mass m
(known)
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MRI/PET
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Summary

• Technologies of H.E. Physics are applied for PET
• Liq. Xe TPC is the main detector
• Scintillation is also used for time stamp and
  rough localization of gamma rays
• Electrons drift along the body axis

• High resolution 3D positions of gamma rays
• Large coverage is possible almost w/o dead space
• High sensitivity
• Possible dynamic imaging
• Possible BG rejection w/ Compton spectrometer and
  TOF
• Compatibility with MRI