Progress in using prompt gammas for ion range monitoring ... 3 Prospects in... · Prompt Gamma Measurements I collimated camera I single and multislit I slit camera I see poster by

Progress in using prompt gammas for ionrange monitoring during hadrontherapy

J. Krimmer1, M. Chevallier1, J. Constanzo1,M. Dahoumane1, D. Dauvergne1, M. De Rydt1,2, G. Dedes1,N. Freud3, J.M. Létang3, M. Pinto1, C. Ray1, V. Reithinger1,M.H. Richard1,3, F. Roellinghof1,3,4, E. Testa1, A.H. Walenta1

1IPNL, 2K.U. Leuven, 3CREATIS, 4IBA

ICTR-PHE 2012Geneva, Switzerland

J. Krimmer (IPNL) Progress in using prompt gammas for ion range monitoring during hadrontherapy ICTR-PHE 2012

Dose Monitoring during Hadrontherapymeasurement of β+ activity(200 MeV/u 12C on a PMMA phantom)

Target depth [cm]0 0.5 1 1.5 2 2.5 3

coun

ts/io

n/m

m

0.005

0.01

0.015

0.02

0.025

0.03 γ

n

p

α

nuclear reactions

C, PMMA target, GEANT4.9.41295MeV/u

goalI 3D reconstruction of applied dose (online)

techniquesI β+ activity ⇒ PETI emitted radiation (p,γ) for ion range monitoring

I proton IVI ⇒ talk E. Testa Wed. 15:45 (Nr. 241)I prompt γ ⇒ this talk


Prompt Gamma Measurements

I collimated cameraI single and multislit

I slit cameraI see poster by J. Smeets

(Nr. 89)

I Compton cameraI "electronic collimation"


Common Device: Hodoscopehardware

I array of scintillating fibres(1 mm x 1 mm)

I 2 prototypes: 2x32and 2x128 fibres

I multianode PM or MCP-PMTI time resolution ≤ 1 nsI goal: count rates up to 108 1/s

electronicsI development of ASIC

S. Deng DOI 10.1109/ICECS.2010.5724447

I first version tested at CAL NiceI new version with DLL ⇒ timing

see poster M. De Rydt (Nr.136)


Collimated Camera95MeV 12C, PMMA target

coun

ts /

ion

0

2e-07

4e-07

6e-07

8e-07

1e-06

1.2e-06

1.4e-06

depth in target [mm]-10 0 10 20 30 40 50

dataQMD improvedQMD default

I measurements at carbon beams (homogeneous targets):I E. Testa et al. Appl. Phys. Lett. 93 (2008) 093506I E. Testa et al. NIM B 297 (2009) 993I M. Testa et al. Radiat. Environ. Biophys. 49 (2010) 337

I improvements in simulations (GEANT4):I G. Dedes poster (Nr.148)


Target Dependence (GANIL)PMMA (1.2 g/cm3)

C12



C12

PMMA+teflon(2.3 g/cm3)

C12



C12

PMMA+teflon(2.3 g/cm3)

C12

PMMA+lung(0.2 g/cm3)

C12


First Measurement at the Proton Beamsetup

LaBr3

proton beam

PMMA target

LYSO

tungstencollimator

I proton beam 160 MeVat WPE (Essen)

I 2 LYSO detectors3 x 40 x 50 mm3

I 1 LaBr3 detectorø25.4 mm x 50.1 mm

I W collimator (100 mm)

results of a scan

I TOF selection:background reduction

I see talk of F. RoellinghoffWed. 15:00, (Nr. 235)


Multi-Slit Collimatorsparallel collimator

I GANIL, 13C 73 MeV/u on PMMA

Longitudinal position (mm)-10 -5 0 5 10 15 20 25

Cou

nt p

er in

cide

nt io

n

0

0.5

1

1.5

2

2.5

3

-610×

With TOF selection

Without TOF selection

convergent collimator


Compton CameraI intersection: line/cone


Compton Camera: Simulations

I scatterer: 10 silicon strip detectors (SSD) 80 x 80 x 2 mm3

I absorber: LYSO detector 300 x 300 x 25 mm3

I photons: point sourceI simulation: hit in SSD + hit in absorberI resolution: 8 mm FWHMI efficiency: 3·10−4

F. Roellinghoff et al. NIM A 648 (2011) S20-S23M.H. Richard et al. proceedings IEEE NSS-MIC (2011), Valencia


Compton Camera: Hardware

E [keV]20 40 60 80 100 120 140 160

cts/

s

-210

= 121.8 keVγ = 40keV and Eγ152Eu E

I Double-sided Silicon Strip DetectorsI test detectors (12 x 12 x 2mm3)I 8 strips on each sideI energy resolution ∆E=10 keV

goal: ∆E< 2 keV ⇒ cooling neededI delivery of final DSSD detectors (90 x 90 x 2mm3),

2x64 strips, expected 2012


Test Measurements: HIT (Heidelberg) carbon

3LaBr det.

beamtarget

scint. beam I.C.

scint. CCsilicon det.

14

0

17

3

E [keV]1000 2000 3000 4000 5000 6000 7000

cts/

s

-210

-110

1

10

LaBr3

C 310 MeV/u12beam backgrounddifferencecut on scint. beam

I single ratesI silicon detector: 2.5 · 10−4 cts/ion (scaler, thres. 350 keV)I absorber: 4.5 · 10−3 cts/ion (scaler, thresh 180 keV)

I coincidence ratesI all events: 2.6 · 10−5 cts/ion (scaler)I uncharged: 2.9 · 10−6 cts/ion (software cuts)

I extrapolation to prototype dimensionsI silicon det.: 1.4 · 10−2 cts/ion singleI absorber: 6.6 · 10−2 cts/ion single


Test Measurements: HIT (Heidelberg) protons

3LaBr det.

beamtarget

scint. beam I.C.

scint. CCsilicon det.

14

0

17

3

E [keV]1000 2000 3000 4000 5000 6000 7000

cts/

s

-210

-110

1

LaBr3

beam p 160 MeVbackgrounddifference

I single ratesI silicon detector: 8.9 · 10−6 cts/ion (scaler, thres. 350 keV)I absorber: 4.3 · 10−4 cts/ion (scaler, thresh 180 keV)

I coincidence ratesI all events: 1.7 · 10−7 cts/ion (scaler)I uncharged: 9.2 · 10−8 cts/ion (software cuts)

I extrapolation to prototype dimensionsI silicon det.: 5 · 10−4 cts/ion singleI absorber: 6.3 · 10−3 cts/ion single

I for protontherapy conditions (1010 p/s)absorber needs to be segmented


Summary and Outlook

I Collimated CameraI prompt γ profiles for p and carbon beamsI TOF selection necessaryI improvements in simulationsI convergent multi-slit collimator

I Compton CameraI simulation and test measurementsI count ratesI cooling for SSDI absorber


Documents

Progress in using prompt gammas for ion range monitoring ... 3 Prospects in... · Prompt Gamma Measurements I collimated camera I single and multislit I slit camera I see poster by