1 / 37

Michiaki Takahashi N. Higashi, S. Iwaki, S. Kabuki, H. Kubo, S. Kurosawa,

Development of an Electron-Tracking Compton Camera using CF 4 gas at high pressure for improved detection efficiency. Michiaki Takahashi N. Higashi, S. Iwaki, S. Kabuki, H. Kubo, S. Kurosawa, K. Miuchi, K. Nakamura, J. D. Parker, T. Sawano, A. Takada A , T. Tanimori, K. Taniue, and K. Ueno.

manju
Download Presentation

Michiaki Takahashi N. Higashi, S. Iwaki, S. Kabuki, H. Kubo, S. Kurosawa,

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Development of anElectron-Tracking Compton Camera using CF4 gas at high pressurefor improved detection efficiency Michiaki Takahashi N. Higashi, S. Iwaki, S. Kabuki, H. Kubo, S. Kurosawa, K. Miuchi, K. Nakamura, J. D. Parker, T. Sawano, A. TakadaA, T. Tanimori, K. Taniue, and K. Ueno Dept. of Physics, Graduate school of Science, Kyoto University, Kyoto, Japan AISAS/JAXA, Kanagawa, Japan The Twelfth Vienna Conference on Instrumentation, Vienna, Austria 20 February 2010

  2. Outline ・ Introduction  Electron-Tracking Compton Camera (ETCC)  Medical imaging / MeV gamma-ray astronomy ・　Optimization of gas mixture ・　Operation at high pressure ・　Summary

  3. １ 2 3 2 events 10 100 5 Electron-Tracking Compton Camera (ETCC) μTPC (Time Projection Chamber） --- 3D track and energy of Compton-recoil electron Scintillation camera --- position and energy of scattered gamma ray e- μPIC GEM Scintillator •  Determination of direction and energy of each incident gamma ray • Large FOV (  3 sr) B26 K. Ueno, A22 S. Kurosawa

  4. 10cm TPC (Time Projection Chamber) for 3D electron track GEM (Gas Electron Multiplier) (F. Sauli (1997)) + μPIC (micro PIxel Chamber)  2D readout micro pattern gaseous detector  2D readout+ Drift time  3D track Electric field Prototype TPC size : 10×10×10 cm3 Gas: Ar/C2H6 (90:10)at 1 atm, sealed Position resolution :  150 m (1D) Stable gas gain :  30000 (PIC :  3000, GEM :  10) Example of 3D track 400 m pitch Proton Electron cathode 10 cm anode

  5. GSO and LaBr3 Scintillation Cameras • 15 x 15 cm2 Camera • (GSO or LaBr3 • + Multi anode PMT (H8500, HPK)) • Number of pixels: 576 • Pixel size 6×6×13mm3(GSO) • 6×6×15 or 20 mm3(LaBr3) • GSO Energy resolution :10.0 % (@662keV, FWHM) • LaBr3 Energy resolution: 6.5% (@662keV, FWHM) • Position resolution: 6mm 15 cm GSO 8×8 Pixel 6 mm 13 mm Black :GSO Red : LaBr3 5 cm

  6. MeV gamma-ray camera projects • Medical: Advantage point: • wide energy dynamic range (300 – 3000 keV) and wide FOV • (SPECT < 300 keV, PET 511 keV) • 1. Multi RI Tracer Imaging • --- The development of new RI drugs • 2. Proton Therapy • --- Real time monitor of prompt gamma rays • to measure Bragg-peak position • Astronomy: • Sub-MeV gamma-ray Imaging Loaded-on-balloon Experiment(SMILE) • 1. SMILE-I (2006, launched) • Operation test of ETCC @35 km • Measurement of diffuse cosmic and • atmospheric gamma rays ( 400 photons)  4 hours • 2. SMILE-II (2011) • Observation of Crab Nebula or CygnusX-1 3 hours Scinti : LaBr3 Scinti : GSO

  7. Examples of Medical Imaging ETCC for medical use Zn-65-Porphyrin imaging (1116 keV) Porphyrin was accumulated in RGK-36 which is the tumor of rat stomach cancer. 180cm Scintillator γ TPC Spatial resolution  10 mm (FWHM) ETCC/CT 60cm Scinti : LaBr3 ETCC/CT 365 keV (Tumor) 511keV (Brown fat cell) Activity : 0.16 MBq Time : 110.5 hours Events : 173 events Energy window : ±10% 1004  1228 keV 2 sources imaging Time : 6 hours

  8. For High Sensitivity Increase detection area • Multi-head camera (10×10×10 cm3×2,3,…) • Developing a large size ETCC (30×30×30 cm3) Improvement of detection efficiency • Optimization of gas • Operation at high pressure 2 times better than our prototypes

  9. Selection of gas sealed in TPC Ar/C2H6 (90:10) CF4 gas mixture Merit of CF 4gas Small diffusion  better position resolution (for TPC)  better angular resolution (for ETCC) low Z (C : Z=6, F: Z=9) and 42 electrons in one molecule  Compton scattering is dominant  higher efficiency (for ETCC) Demerit of CF 4gas Low gas gain  isoC4H10gas (penning effect) High dependence of drift velocity on electric field  worse position resolution ?

  10. Optimize the gas mixture Drift Cage TPC 10 cm Electronics 10 cm 10 cm source Gas Ar/C2H6 (90:10) Ar CF4 isoC4H10 GEM (SciEnergy) • Measurement • Gas Gain • Position Resolution Requirements : High CF4ratio Gas Gain 20,000 PIC

  11. Gas Gain at 1 atm Penning effect of isoC4H10  The other GEM = 400V GEM = 340V This gas CF4 45% CF4 50% CF4 20% CF4 30% CF4 40% Improved by more than 2 by introducing isoC4H10

  12. Position Resolution muon tracks = 156m D= 175m/cm1/2 Ar/C2H6 (90:10) Ar/CF4/isoC4H10 (54:40:6) Better by factor 2 = 162m D= 81m/cm1/2 l : Drift length D : Diffusion Constant

  13. Drift Plane (Al Mylar) High Pressure 100 mm 100 mt GEM TPC 2 mm 2 mm Electronics PIC source 100 mm 50 mt GEM Ar/C2H6 (90:10)at 1 atm Ar/C2H6 (90:10)at 2atm Ar/CF4/isoC4H10 (54:40:6)at 1atm Ar/CF4/isoC4H10 (54:40:6)at 1.4atm • Measurement • Gas Gain • Drift Velocity • Position Resolution • Energy Resolution

  14. Gas Gain Upper GEM = 350V Lower GEM = 250V Lower gas gain Upper GEM = 460V Lower GEM = 360V Upper GEM = 610V Lower GEM = 450V Upper GEM = 500V Lower GEM = 380V

  15. Drift Velocity Difference between simulationand measurement is smaller than 10%

  16. Position Resolution Ar/C2H6 (90:10) at 2 atm Ar/C2H6 (90:10) at 1 atm • = 332 m, D = 246 m/cm1/2 • = 302 m, D = 204 m/cm1/2 Better by factor 1.6 Better by factor 2 Ar/CF4/isoC4H10 (54:40:6) at 1 atm Ar/CF4/isoC4H10 (54:40:6) at 1.4atm • = 378 m, D = 147 m/cm1/2 • = 330 m, D = 128 m/cm1/2

  17. Energy Resolution31 keV X-ray from 133Ba (31 keV) Ar/C2H6 (90:10)at 1 atm Ar/C2H6 (90:10)at 2 atm Worse than prototype 43.8% (FWHM) @31 keV 53.1% (FWHM) @31 keV Ar/CF4/isoC4H10 (54:40:6)at 1.4 atm Ar/CF4/isoC4H10 (54:40:6)at 1 atm 56.1% (FWHM) @31 keV 60.0% (FWHM) @31 keV

  18. Imaging with ETCC gamma-ray from 133Ba (356 keV, 800 kBq) ARM : Angular Resolution Measure SPD : Scatter Plane Deviation Electronics TPC 15 cm Measurement Efficiency Angular resolution (ARM and SPD) GSO Scintillation Camera source

  19. 50 SMILE-I 2006 (Xe + GSO) 10 ARM (FWHM) [degree] Ar/C2H6 TPC + GSOscintillator the highest spec. 5 1 Efficiency and Angular Resolution(133Ba 356 keV) better by factor 1.94 This Work (GSO) Ar/C2H6 TPC + LaBr3scintillator Ar/CF4/isoC4H10 (54:40:6) at 1.4atm Imaging of 133Ba 15 cm away from top of TPC

  20. Summary • In order to improve the efficiency of the ETCC, we have optimized the gas mixture and pressure sealed in the TPC. • The highest ratio of CF4gas with steadygas gain of  20,000 is Ar/CF4/isoC4H10 (54:40:6). • The diffusion constant of Ar/CF4/isoC4H10 (54:40:6) is 2 times better than that of Ar/C2H6 (90:10), so the position resolution is improved. • The efficiency for the ETCC using Ar/CF4/isoC4H10 (54:40:6)at 1.4 atm is2 times higher than that using Ar/C2H6 (90:10) at 1atm, and those ARMs are comparable (11 at 356 keV (FWHM)).

  21. Thank youfor your attention

  22. Vs. Conventional Compton Camera Advanced Our ETCC Conventional COMPTEL Measure the 3-D track of a Recoil electron DO NOT measure the track of a Recoil electron • Reconstruction : point • Direction error region: arc • Reconstruction : circle • Direction error region : donut 15 15 150 events Y [cm] Y [cm] 600 events -15 -15 -15 X [cm] 15 -15 X [cm] 15 137Cs(1MBq)2, Advanced Compton 137Cs(1MBq)2, Classical Compton

  23. 6 mm 13mm Position-Sensitive Scintillation Camera GSO(Ce) 8x8 pixels Pixel size: 6x6x13mm3 0.8 0.4 0 -0.4 -0.8 500 400 300 200 100 0 Y-position (a. u) 5cm 137Cs 5cm Multi-anode Photo Multiplier Tube (PMT) HPK H85008x8 anodes Counts (a. u.) -0.8 -0.4 0 0.4 0.8 X-position (a. u.) Dynamic energy range: 0.08 -1 MeV Eng. Resolution: 10.5 % @662 keV 2-D image in flood-field irradiation

  24. Assembly of LaBr3(Ce)array Using our technique, we assembled an 88 array. 133Ba GSO monolithic LaBr3 monolithic E/E = 4.1 0.1 % @ 356 keV (FWHM) GSO array 6.1 mm pitch (=multi-anode PMT H8500 anode pitch) LaBr3 array 54mm 20mm GSO FWHM(%)= (10.40.3)(E/662keV)-0.510.01 LaBr3：hygroscopic LaBr3 FWHM(%)= (5.70.4) (E/662keV)-0.530.01 Hermetic package

  25. Incident  Sci. Eng. Res. @662keV ETCC. Angular Res. @662keV(FWHM) φAngular resolution (ARM) 10.5 % 4.2 7% 3.1 5% 2.3 3% 2.1 Scattering angle φ Recoil e- K: energy  Scattered  E : energy Calculated assuming 1, no error in position of Compton point 2, energy Res. of TPC : 30 % @ 22 keV Angular Res. Simulation including mTPC Angular resolution (FWHM) [degree] Doppler broadening (Ar) Zoglauer et al. (2003) Eng. Res. (FWHM) of LaBr3(Ce) : ~ 3 % @ 662 keV Loef et al. (2001)

  26. Energy Dynamic Range Measured sources SPECT PET Energy dynamic range : 167 – 1333 keV.

  27. Spatial Resolution Spatial resolution vs. Energy Goal : Same resolution as human PET @ 511keV

  28. I-131-MIBG & F-18-FDG imaging (365 & 511 keV) Dept. of Bioanalysis, Kyoto University H. Kimura, H. Amano and H. Saji Scinti : LaBr3 PET/SPECT/CT PC12 PC12 6cm Brown fat cell Brown fat cell Rainbow： 511keV Orange： 365keV Rainbow： PET Orange： SPECT

  29. Zn-65 mouse imaging 3x3 LaBr3 Install to 10cm-ETCC Measurement after dissection Liver :0.04 MBq Spleen :0.02 Pancreas:0.02 Heart :0.02 Stomach : 0.01 Kidney : 0.00 Intestinal:0.11 Brain :0.02 Other :0.79 BG :0.03 Mouse Zn-65 imaging Energy : 1116keV activity : 1.4MBq obs. time : 2784 min Events : 629 events Zn is a good tracer for diabetes

  30. All kinds of experiment gas(45types) CF4base Fixing CF4ratio changing Arand isoC4H10 ratio Ar/C2H6 (90:10) base

  31. -PIC :2-D gaseous detector 400μm pitch Size: 10 cm x 10 cm Pixel pitch: 400 m ~ 65,000 pixels Gas gain:  ~6,000 (stable operation of more than 1 month) anode 10cm cathode Cu

  32. -PIC : gain and Energy spectrum We filled with Ar(90%) + C2H6(10%) gas at 1atm E/E 30% @ 5.9 keV Ar-escape 0 2 4 6 8 10 Energy [keV] Gas gain uniformity RMS ~ 7% Energy spectrum (55Fe)

  33. X-ray imaging with -PIC AMP-Discri. Board Based on a chip for ATLAS Thin Gap Chamber 0.8V/pC 1 mm Test chart image Test chart image Position resolution: 120 m

  34. Simulation study Gamma rays proton Water phantom neutron Simulation 511keV 2.2MeV Gamma rays neutron Proton Therapy Attack on Cancerous cells 200MeV Monitoring Before treatment: ionization chamber After treatment: PET technique (PET: positron emission tomography) Real time : none 150MeV proton Depth in Tissue (water) [mm] • ETCC : • ability to detect Prompt gamma rays as the monitor • Wide energy range (0.1-10 MeV) • Rejection of Neutron • Wide field of view (~3 str.)

  35. We are developing a monitor for Proton Therapy ETCC (10cm)3 TPC 160 MeV Proton Water Phantom collaborator : J. Kim (Research Institute and Hospital, National Cancer Center, Korea) 30cm Experiment in Osaka Univ. Research Center for Nuclear Physics (RCNP)

  36. Sensitivity in X / Gamma-ray Astronomy [ eV ] energy bad keV MeV GeV TeV EGRET 1mCrab Air Cherenkov Fermi continuous sensitivity[erg/cm2/sec] suzaku HXD Our goal ～１ ° good

  37. 10-2 10-4 10-6 10-8 10-1 10-3 10-5 10-7 Previous results Previous results Flux [photons / (cm2 sec str keV)] Flux [photons / (cm2 sec str keV (g / cm2))] SMILE-1 SMILE-1 10 102 103 104 105 [Energy] 10 102 103 104 105 [Energy] Energy spectrum atmospheric  rays diffuse cosmic  rays We detected 420 photons (Total) @0.15-1 MeV, 32-35 km for 4 hours

More Related