1. Fragmentation experiments
Status Report
LNS
C.Agodi TPS collaboration meeting
Torino 5-6 novembre 2009

2. What is the contribution to Ion Therapy Treatment Planning ?
The Treatment Planning Systems (TPS) is a complex computer system that helps both to design radiation treatments and to compute the dose to the patient.
The optimal TPS should be interactive and evaluated in real time.
Innovative contribution in this field is particularly needed in case of clinical ions beams.
Computed Tomography
Energy losses can be assessed via Monte Carlo simulation mainly to account for fragmentation nuclear processes.
Cross section fragmentation data
Planning Treatment Volume
RBE table remodels the physical dose deposition including the hadron specificity
Cross section fragmentation data
LNS

3. Projectile fragmentation
Reaction products :
have velocity near to the primary beam;
are emitted mostly in the forward direction
The detection system has to be efficient in the interest angular region
Projectile
Reaction at
Intermediate energy
Target
Nuclei Fragmentation
LNS

4. In 2010 we plan to use different beams up to 80 AMeV.
Our Measurements at LNS: The Experiment
We already measured the 12C fragmentation on 197Au and 12C targets with 32 and 62 AMeV CS beams at LNS-INFN, Catania
In 2010 we plan to use different beams up to 80 AMeV.
An hodoscope (hodo big and hodo small) composed of two-fold and three-fold telescopes has been used for identify fragments produced in the reaction and measure the energy (θlab between 0° and ±20°)
INFN Laboratory Nazionali del Sud , Catania - Sicily - Italy
12C beam from CS
Target
Hodo Big
Hodo small
LNS – INFN, Catania
Superconducting cyclotron
LNS
LNS

5. Complete characterization
Experimental set – up
projectile fragment
Complete characterization
and coverage near 90%
HODO-BIG: 89 three-folds telescopes array 4.5°-22.5°
Si(50μm)-Si(300μm)-CsI(6cm)
HODO-SMALL: 81 two-folds telescopes array 4.5°-4.5°
Si(300μm)-CsI(10cm)
LNS

6. FRAG (April 2009) 12C+12C,197Au,CH @62MeV
LNS
FRAG (April 2009)
C + C
N° ≈ 5·1012
I ~ 40 – 80 pA
N° ≈ 1·1012
C + CH2
I ~ 40 – 60 pA
C + Au
N° ≈ 11·1012
I ~ 180 – 230 pA

7. DE-E plot
LNS

8. Measured vs calculated angular differential cross sections

9. CHARGED PARTICLE PRODUCTION CROSS SECTION
PRELIMINARY COMPARISONS – LNS DATA AT 62 AMeV Carbon incident
General better agreement of JQMD with our modifications but still worse agreement in the intermediate part of the spectra
LNS

10. Proposal of Experiment at SIS
“Extensive study of nuclear reactions of interest for medical and space applications.”
G.Cuttone, F.Marchetto, G.Raciti, E.Iarocci, V.Patera, C.Agodi, C.Sfienti, E.Rapisarda, M. De Napoli, F. Giacoppo, M.C. Morone, A. Sciubba, G.Battistoni, P.Sala, Sacchi, E.Spiriti, G.A.P.Cirrone, F.Romano
INFN: LNS, LNF, Roma2, Roma3, Milan, Turin, Roma Tor Vergata
S.Leray, M.D. Salsac, A.Boudard, J.E. Ducret, M. Labalme, F. Haas, C. Ray
DSM/IRFU/SPhN CEA Saclay, IN2P3 Caen, Strasbourg, Lyon
M. Durante, D. Schardt, R. Pleskac, T. Aumann, C. Scheidenberger, A. Kelic, M.V.Ricciardi, K.Boretzky, M. Heil, H. Simon, M. Winkler
GSI
P. Nieminen, G. Santin
ESA
LNS

11. GSI-GPAC: «Extensive study of nuclear reactions of interest for Medical and Space Applications»: S371
LNS

12. We can get the goal of 3% error in Double Differential Cross Section
Estimation of the systematic errors on momentum and angle as reconstructed with ALADIN
Assuming that the dependence of the acceptance on Pt can be determined with a 20% error then all the slopes should be determined with an accuracy better than 2.5 %, in the worst case (Z = 2)
We can get the goal of 3% error in Double Differential Cross Section

13. Fragmentation measurements at GSI
The G-PAC approved with high priority the key measurements:
0.2, 0.4 and 1.0 AGeV
0.2, 0.4 AGeV
0.2, 0.4 AGeV
LNS

14. Fragmentation 2010 Analysis Exp.Apr.09 LNS@80AMeV S371@GSI LNS
Hadrotherapy
Analysis Exp.Apr.09
(deadline proposal 12/09)
LNS

15. 12C Fragmentation measurements
In order to perform a systematic study of projectile fragmentation intermediate energies, we measured the 12C fragmentation cross section on different targets at 32 and 62 AMeV at LNS.
New mixed inner
radiation field !
projectile
target
projectile fragment
target fragment
Outer radiation fields
Interaction of the radiation with
the spacecraft hulls, the body...
Target Fragments Projectile fragments
… lower charge … lower charge
than target than primaries
… high LET … mixed LET
… short ranges … long ranges
LNS

16. Sezione d’urto di produzione di particelle cariche ( particelle α)
CONFRONTO PRELIMINARE – DATI LNS (12C at 62 AMeV)
In generale miglior accordo con il JQMD con le nostre modifiche .
Resta comunque una discrepanza notevole nella parte intermedia dello spettro
LNS

17. Why fragmentation measurement in hadrontherapy?
LNS
Why fragmentation measurement in hadrontherapy?
Light ions Advantages
Better Spatial selectivity in dose deposition: Bragg Peak
Reduced lateral and longitudinal diffusion
High Conformal dose deposition
High Biological effectiveness
Treatment of highly radiation resistent tumours, sparing surrounding OAR
Disadvantages
Fall of dose in the tumour target region
Unwanted dose in normal tissue behind the target volume
An extensive database on nuclear fragmentation cross sections and fluences are needed at therapeutic energy region
Il metodo Monte Carlo in radioterapia - pratica clinica e strumenti tecnologici 17

18. Disadvantages of carbon ions
LNS
Disadvantages of carbon ions
Nuclear Fragmentation of 12C beam in the interaction processes with:
energy degraders,
biological tissues
Further problem different biological effectiveness of the fragments
Mitigation and attenuation of the primary beam
Dose over the Bragg Peak :
p ~ 1-2 %
C ~ 15 %
Ne ~ 30 %
Production of fragments with higher range vs primary ions

19. Carbon ions advantages
LNS
Carbon ions advantages
Lower lateral and longitudinal diffusion vs. proton
More precise energy deposition
Optimal RBE profile - penetration depth position.
Online PET for depth deposition monitoring
Good Compromise between RBE and OER.

20. Our Measurements at LNS: The Experiment
Target
Hodo Small
Hodo Big
E CsI(Tl)
The Hodo-small, set up at a distance of 80 cm from the target consisted of 81 two-fold telescopes: 300 µm Silicon detectors 1x1 cm2 of active area followed by a 1x1 cm2 and 10 cm long CsI(Tl) and covered the angular range θlab=±4.5°.
The Hodo-big, set up at a distance of 0.6 m from the target, consisted of 89 three-fold telescopes 50 µm µm Silicon detectors both having 3x3 cm2 surface followed by a 6 cm long CsI(Tl)of the same surface. It covered the angular range θlab between ±4.5° and ±20°
LNS