CALISTE and its applications

Transcription

1 CALISTE and its applications Daniel Maier 1, P.A. Bausson 2, C. Blondel 1, F. Carrel 3, G. Daniel 1, C. Force 3, O. Gevin 2, H. Lemaire 3, O. Limousin 1, D. Renaud 1, J. Martignac 1, A. Meuris 1, V. Schoepff 3, F. Soufflet 4, M.C. Vassal 4, F. Visticot CEA Saclay IRFU/DAp, CEA Saclay IRFU/DEDIP, 3 4 CEA Saclay LIST/LCAE, 3D plus SEPT, 26th 217, CEA, Saclay, France

2 SUMMARY CALISTE: a compact X-ray spectro-imager module ORIGAMIX: a portable X- and gamma-ray spectro-imaging camera SATBOT: realtime dosimetry for radiotherapy history IDeF-X family CALISTE family history of the project fields of application physical concepts actual status next steps NP + radiotherapy XRF dosimetry physical concepts actual status next steps Daniel Maier SEPT 217 PAGE 2

3 PROJECT HISTORY CALISTE is based on a long line of experience but also aims for challenging new developments based on IDeF-X readout ASICs - started in 23; now in 7 th generation - properties: ultra-low noise, low power consumption, channel individual triggered readout integrated into a CALISTE module - combining several ASICs - 3D electronics by 3D+ different combinations of ASICs + housing CALISTE-64 CALISTE-256 CALISTE-HD CALISTE-SO D2R1 CALISTE-HD-BD more pixel less power better spec. & spat. resolution larger energy range mW 2mW 9μm 3μm 25 kev 1 MeV 9 ev 58 ev 6keV Daniel Maier SEPT 217 PAGE 3

4 PROJECT HISTORY ORIGAMIX uses a CALISTE module (HD or O) and builds a portable device a portable device stable & safe housing ensure vacuum tightness cooling? compact, low-power electronics power supply: batteries, HV? control of operation software user-friendly mostly autonomous reliability parameters calibration analysis easy to use and to understand alert design: HV crystal bias Wix CALISTE SC & DAQ Interface board MicroZed Zynq SoC Eth.5 mm Al entrance window Carrier motherboard Power management CALISTE HD 2x TEC modules Flex PCB connexion House keeping HV cable Daniel Maier SEPT 217 PAGE 4

5 CURRENT STATUS detector: Caliste-HD 1 x 1 x 1 mm³ CdTe camera: system-on-chip aq. system thermo-electrical coolers dimension: 7.5 x 7.5 x 23 cm³ mass: m < 1 kg power: p < 1 W Daniel Maier SEPT 217 PAGE 5

6 TYPICAL FIELDS OF APPLICATION we have a few ideas on that... inspection after nuclear accidents Daniel Maier SEPT 217 PAGE 6

7 TYPICAL FIELDS OF APPLICATION we have a few ideas on that... inspection after nuclear accidents monitoring areas medical imaging / radiotherapy safety inspections... but there might be others... Daniel Maier SEPT 217 PAGE 6

8 PHYSICAL CONCEPTS CdTe is becomming inefficient for E > 1-3 kev. Then, Compton scattering gets the dominant effect. photon interactions detection efficiency cross section [barn/atom] (a) (b) photon interaction with CdTe (Z Cd = 48, Z Te = 52) coherent scattering (a) incoherent scattering (b) photoelectirc absorption (c) nuclear pair production (d) electronic pair production (e) total (f) (c) (d) (f) interaction probability [%] CdTe d =.5 mm d = 1. mm d = 2. mm d = 3. mm d = 5. mm P.E. only P.E. + I.S photon energy E [kev] photon energy E [kev] (e) P.E. = photo electric absorption I.S. = incoherent scattering ("Compton") Daniel Maier SEPT 217 PAGE 7

9 PHYSICAL CONCEPTS IMAGING = source location most promising is a two fold approach: mask + Compton coded mask + high spatial resolution + big field-of-view ~ about 5% active area easy solution for low energies Compton imaging - low spatial resolution + nearly 4π field-of-view + 1% "active" area extension to higher energies z photon origin z' source plane S α LED interaction x' β y' LED HED interaction x HED y D < D D = D D > D Daniel Maier SEPT 217 PAGE 8

10 PHYSICAL CONCEPTS SPECTROSCOPY = source identification source separation flux estimation what kind of sources are in the field-of-view? kcnts [] 4 Gd Kα 1,2 what is the flux of the different sources? which source is where? imaging are there multiple sources? subtracting the strongest source Mo Kα 1,2 Mo Kβ 1,2,3 Sn Kα 1,2 W Kα 2 Au Kα 2 + W Kβ 1,3 Au Kα 1 Bi Kα 2 Bi Kα 1 + Au Kβ 1,3 Au Kβ 2 Bi Kβ 1,3 Bi Kβ 2 Bi Lβ 1, Sn Kβ 1,2,3 Gd Kβ 1,2,3 W Kα 1 E [kev] Daniel Maier SEPT 217 PAGE 9

11 CURRENT STATUS several test campaings gave us useful feedback and new ideas test with coded mask (MURA) - 74 MBq Am-241 in 1 m (29 ns/h): source identification within 4 ms - 1 MBq Eu-152 in 1 m (1.2 μs/h): source localization: 7 ang. res. Eu-152 Am-241 Tacq =.4 s Daniel Maier SEPT 217 PAGE 1

12 CURRENT STATUS several test campaings gave us useful feedback and new ideas test with coded mask (MURA) - 74 MBq Am-241 in 1 m (29 ns/h): source identification within 4 ms - 1 MBq Eu-152 in 1 m (1.2 μs/h): source localization: 7 ang. res. Eu-152 Daniel Maier SEPT 217 PAGE 1

13 CURRENT STATUS WIX-HD WIX-O lots of improvements in electronics and mechanics: - improved temperature sensing - enhanced vacuum capacity - pressure sensor added - embedded HV generation - embedded TEC power & control - batteries with charger and power ctrl. CALISTE-HD CALISTE-O CALISTE-HD from space to industry standard: - 16x16 pixels, Schottky CdTe - same power: 2 mw (.8 mw/ch) - same energy range: 2 kev to 1 MeV - 1cm² x 1 mm 2 cm² x 2 mm μm 8 μm pixel pitch CALISTE-O Daniel Maier SEPT 217 PAGE 11

14 CURRENT STATUS CALISTE-O first tests show that all pixel are working spectral resolution: - best pixel: 927 ev 6 kev - all pixel: 1.3 kev 6 kev y , Am-241, 5V, tp2, LT15, all , CALISTE-O, Am-241, 5V, tp2, LT15, singles counts [1 [] 3 ] x energy [kev] Daniel Maier SEPT 217 PAGE 12

15 CURRENT STATUS CALISTE-O aims to detect gamma rays Cs-137 source spectral resolution: - all pixel: 6.7 kev 662 kev cnts [] _ Cs-137 only singles 188 spectral features: - Cu fluorescence (8.8 kev) - Ba Ka and Kb lines (32.1 & 36.6 kev) - Ba* after Cs decay (662 kev) - Compton scattering in the detector (E < 48 kev) kev det Compton scattering outside (E > 188 kev) 662 kev - multiple (>2x) Compton sc. det E [kev] 662 kev det Daniel Maier SEPT 217 PAGE 13

16 NEXT STEPS we are not at the end... test Compton imaging point and interval estimations in x-, y-, and z-directions combining mask and Compton autonomous control HV cycling to prevent CdTe instability pixel individual trigger thresholds optimal peaking time autonomous analysis energy calibration source identification flux / dose estimation Daniel Maier SEPT 217 PAGE 14

17 APPLICATION: medical physics SATBOT: radiotherapy + nano particles multidisciplinary field X-ray tube detector θ Au physics enhanced absorption because of high Z generation of generation of fluorescence radiation enhanced attenuation -> dose enhancement Auger e - photo e - Compton e - chemistry oxidative stress by reactive oxigen species (ROS): H 2 O 2 e - + H 2 OH - surface effec: catalysator coating O 2- chemical enhancement biology accumulation of NP degradation of NP 5 Rs: repair, redistribution reoxygeneration repopulation radiosensitivity Daniel Maier SEPT 217 PAGE 15

18 BASIC PHYSICS XRF detection self absorptoin in humain tissue 1 depth in soft tissue [mm] 1 1 1% 9% 8% 7% 6% 5% 4% 3% 2% 1% Kα1 absorption [%] atomic number Z [] Daniel Maier SEPT 217 PAGE 16

19 BASIC PHYSICS interaction photons humain abs. coeff. μ [1/cm] ICRU 4 components ICRU4 coherent scattering ICRU4 incoherent scattering ICRU4 photo electric absorption. ICRU4 pair creation (nucleus) ICRU4 pair creation (atom) fat blood bones breast energy [kev] Daniel Maier SEPT 217 PAGE 17

20 BASIC PHYSICS XRF dosimetry goal: - determine the concentration of the NP - determine the dose at the tumor level detector F 5 ~69 kev ~78 kev F 5 approach: - prior knowledge of the tube flux - determine the transmittivity t 1 and t 2 - tumor flux = tube flux * t 1 dose - NP concentration ~ meas. flux / tumor flux human tissue with att. coef. μ 1 human tissue with att. coef. μ 2 t 2 d 2 X-ray tube F F F I 4 F 1 F t L 2 F 2 1 F 3 T tumor E +NP R d 1 Daniel Maier SEPT 217 PAGE 18

21 BASIC PHYSICS scattering makes it difficult... coherent scattering incoherent scattering dσ/(sin(θ) dθ) [b/sr/atom ] Si, k = 5 kev Si, k = 662 kev Au, k = 5 kev Au, k = 662 kev dσ/(sin(θ) dθ) [b/sr/atom ] Si, k = 8 kev Si, k = 15 kev Si, k = 2 kev θ [ ] θ [ ] coherent scattering: incoherent scattering: for low energies scattering angle > 9 small effect for all energies of interest scattering angle 9 big effect Daniel Maier SEPT 217 PAGE 19

22 SATBOT results first SATBOT campaign FEB 217: industrial robots for alignment of X-ray tube alignment of detector Daniel Maier SEPT 217 PAGE 2

23 SATBOT results first SATBOT campaign FEB 217: industrial robots for alignment of X-ray tube alignment of detector Daniel Maier SEPT 217 PAGE 2

24 SATBOT results first SATBOT campaign FEB 217: industrial robots for alignment of X-ray tube alignment of detector result Au identification independent of NP size sensitivity: 48 ug Au W/Kα W /Kβ Au/Kα 22/2/217 Nano en solution: 31nm 45nM 5µL Au/Kβ Daniel Maier SEPT 217 PAGE 2

25 SATBOT results second SATBOT campaign APRIL 217: filter for X-ray tube shape the tube spectrum enhance the high energetic part result Count s, normal i zed 1 8 blanc,56 mg Au 1,12 mg Au 2,25 mg Au Au identification for different m Au lin. relation between signal & m Au sensitivity: 38 ug Au ENERGY ( kev) problem: detect a peak on top of a peak! Daniel Maier SEPT 217 PAGE 21

26 SATBOT results third SATBOT campaign AUG 217: filter for X-ray tube result advaced filter flux [1/(s kev cm 2 )] μg Au 115 μg Au 577 μg Au 288 μg Au 144 μg Au μg Au XRF peak in valley clear Ka and Kb detection sensitivity: Ka: 5 ug Au Kb: 3 ug Au Au signal S [cnt/s] E [kev] Au Kα 2 + Kα 1 fit: S Kα =.949 cnt/(s cm 2 μg) m Au Kβ 3 + Kβ 1 fit: S Kβ =.133 cnt/(s cm 2 μg) m 5 E [kev] Au mass m [μg] detection limit Daniel Maier SEPT 217 PAGE 22

27 SATBOT new ideas: advanced X-ray filter E XRF < K-edge only E > K-edge causes XRF background photons E XRF < E < K-edge noise unnecessary photons E < E XRF unnecessary dose X-ray filter without absorption edges X-ray filter near an absorption edge ideal X-ray filter transmittance 1 energy transmittance 1 thin filter thick filter energy transmittance 1 K-edge energy Daniel Maier SEPT 217 PAGE 23

28 SATBOT new ideas: advanced X-ray filter E XRF < K-edge only E > K-edge causes XRF background photons E XRF < E < K-edge noise unnecessary photons E < E XRF unnecessary dose Combine filter with incoherent scattering WIX X-ray camera (CdTe) for fluorescence and scattered radiation X-ray detector (scintillator) for transmitted radiation test sample X-ray beam ortho X-ray tube (14 kv peak) scattered radiation loses energy X-ray beam F I L T E R TARGET θ det. Z filter = Z target + n n << n n > transmittance1 K edge, filter XRF usable photons for XRF K edge, target energy transmittance1 K edge, filter XRF K edge, target usable photons for XRF energy transmittance1 usable photons for XRF XRF K edge, target K edge, filter usable photons for XRF energy Daniel Maier SEPT 217 PAGE 23

29 SATBOT new ideas: advanced X-ray filter Z [] n<< n n > example: for Au: n for Z 73 n< for 74 Z 79 n> for 8 Z 84 Z [] Daniel Maier SEPT 217 PAGE 24

30 SATBOT new ideas: advanced X-ray filter Which filter and which observation angle should we choose? energy [kev] n=-5 n=-4 n=-3 n=-2 n=-1 n= n=1 n=2 n=3 n=4 n= θ K α1 K edge Compton sc. K edge color atomic number Z [] Daniel Maier SEPT 217 PAGE 25

31 SATBOT new ideas: advanced X-ray filter How thick should the filter be? signal analysis: flux after filter flux before filter relative photoelectric cross section [] cumulative photoelectric distribution [] E [kev] E [kev] Daniel Maier SEPT 217 PAGE 26

32 SATBOT new ideas: advanced X-ray filter How thick should the filter be? noise analysis: unfiltered flux F 1 (E) filtered flux F 2 (E), Au-filter: 15 µm, 3 µm, 6 µm filtered flux F 2 res (E), Au-filter: 15 µm, 3 µm, 6 µm E max = 15 kev flux F [cnt/(s kev cm 2 ].1.1 flux F [cnt/(s kev cm 2 ] flux F [cnt/(s kev cm 2 ] energy E [kev] energy E [kev] energy E [kev] 1 unfiltered flux F 1 (E) 1. filtered flux F 2 (E), Au-filter: 15 µm, 3 µm, 6 µm filtered flux F 2 res (E), Au-filter: 15 µm, 3 µm, 6 µm E max = 64 kev flux F [cnt/(s kev cm 2 ].1.1 flux F [cnt/(s kev cm 2 ] flux F [cnt/(s kev cm 2 ] energy E [kev] energy E [kev] energy E [kev] Daniel Maier SEPT 217 PAGE 27

33 SATBOT new ideas: advanced X-ray filter How thick should the filter be? maximize signal-to-noise ratio add a constant background flux 1 Gold (Z = 8; n = ; θ = 13 ) SNR [] filter thk [mm] Daniel Maier SEPT 217 PAGE 28

34 SATBOT new ideas: advanced X-ray filter How thick should the filter be? a filter can make it worse a higher voltage of the X-ray tube makes the SNR always better ;-) the optimal filter thickness is independent of the chosen voltage Daniel Maier SEPT 217 PAGE 29

35 SATBOT conclusions SATBOT is a very dynamic project the work is very interdisciplinary next steps: new filter: sensitivity < 2 ug XRF tomography Daniel Maier SEPT 217 PAGE 3

36 SATBOT conclusions the SATBOT team is very nice Daniel Maier SEPT 217 PAGE 31