Istituto Nazionale di Fisica Nucleare Laboratori Nazionali del Sud Catania LNS LNS Clementina Agodi...
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Transcript of Istituto Nazionale di Fisica Nucleare Laboratori Nazionali del Sud Catania LNS LNS Clementina Agodi...
Istituto Nazionale di Fisica Nucleare Laboratori Nazionali del Sud Catania
LNSLNS
Clementina Agodi
FIRST experiment:
Fragmentation of Ions Relevants for Space and Therapy
11TH International Conference on NUCLEUS NUCLEUS COLLISIONSMay 27-June 1, 2012 San Antonio, TEXAS, USA
FIRST experiment at GSI
• Introduction
• The FIRST experimental set-up
• 12C Fragmentation measurements at GSI
• Summary & Perspective
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Hadrontherapy MotivationHadrontherapy MotivationLight ions advantages in radiation
treatments :
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
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CARBON IONS ADVANTAGESCARBON 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.
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DISADVANTAGES OF CARBON IONSDISADVANTAGES OF CARBON IONS
Nuclear Fragmentation of 12C beam in the interaction processes with: energy degraders, biological tissues
Further problem different biological effectiveness of the fragmentsMitigation 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
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Nuclear fragmentation and Models
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• Simulations with analytical codes are used to estimate how projectile fragmentation modifies dose distribution and biological effectveness.
• Such approach presents considerable uncertainty in the models implemented because of a reduced number of experimental data, both on the fragmentation cross sections and on the different quality of radiations biological effectiveness.
Most of these measurements are limited to yields or total charge fragmentation cross-sections (in water or tissue equivalent), while the needed measurements of high precision (ΔM/M) d2/ddE double-differential cross-section are scarce.
12C , E
12C , E'
,A,Z
',A',Z'
X,Ex,x,x
Y,Ey,y,y
NASA Space Radiation Program Goal:To live and work safely in space with acceptable risks from radiation
*Francis A. Cucinotta (NASA, Lyndon B. Johnson Space Center), private communication
Solar particle events (SPE)about 90% protons, E<1 GeV, about 90% protons, E<1 GeV, seldom but potentially seldom but potentially dangerous (highdose)eventsdangerous (highdose)events(generally associated with Coronal Mass Ejections from the Sun
Trapped Radiation:Van Allen belts (electrons, Van Allen belts (electrons, protons up to 600 MeV)protons up to 600 MeV)
Galactic Cosmic Rays (GCR)•2% electrons and positrons •98% particles :
87% protons •12% α particles•1% heavier ions (HZE particles)
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GCR reach earth rarely, but become relevant for exposure into interplanetary flights, that are the NASA future plans
The Space Radiation Environment
Space radiation risks assessment
Fe
Fe
C
C
Nuclear fragmentation measurements in Hadrontherapy and Space radiation risks assessment
Mixed fields of charged particles are present in astronauts environment and patients treated with carbon ions
Similar Nuclear Physics processes involved. Energy and mass range are very close Dose calculation and radiological risk assessment required
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Hadrontherapy Spatial vehicles shieldings
NASA completed a large database of nuclear fragmentation measurements (J.W.. Norbury and 1. Miller ,47th NCRP Annual Meeting ,Bethesda , MD , pp. 24 (2011)) and observed that there are ion types and kinetic energy ranges that are missing. In particular, DDCS measurements for light ions in the energy range of interest for hadron therapy applications are lacking.
The FIRST collaboration
INFN: Cagliari,LNF,LNS,Milano,Roma3,Torino: C.Agodi, G.Battistoni, M.Carpinelli, G.A.P.Cirrone, G.Cuttone , M.De Napoli, B.Golosio, Y.Hannan, E.Iarocci, F.Iazzi,
R.Introzzi, A.Mairani, V.Monaco, M.C.Morone,P.Oliva, A.Paoloni, V.Patera, L.Piersanti, N.Randazzo, F.Romano, R.Sacchi, P.Sala, A.Sarti, A.Sciubba, C.Sfienti, V.Sipala,
E.Spiriti DSM/IRFU/SPhN CEA Saclay, IN2P3 Caen, Strasbourg, Lyon: S.Leray, M.D.Salsac,
A.Boudard, J.E. Ducret, M. Labalme, F. Haas, C.Ray GSI: M.Durante, D.Schardt, R.Pleskac, T.Aumann, C.Scheidenberger, A.Kelic,
M.V.Ricciardi, K.Boretzky, M.Heil, H.Simon, M.Winkler University Sevilla & CNA: J.M. Quesada, A.Bocci, J.P.Fernandez-Garcia, M. I.
Gallardo, M.A. Cortes-Giraldo, M.A.G. Alvarez ESA: P.Nieminem, G.Santin
CERN: T.Bohlen
Fragmentation of Ions Relevants for Space and Therapy
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Fragmentation measurements at GSIFragmentation measurements at GSI LNSLNS
FIRST al GSI ( 1-14 August 2011)
Fragmentation of Ions Relevant for Space and TherapyThe experiment at the SIS accelerator of GSI in Darmstadt, has been designed for measurements of ion fragmentation cross sections at different energies between 100 and 1000 MeV/nucleon.
Collected around 18 ml of events 12C+12C @400 Mev/A
Collected around 2 ml of events 12C+197Au @400 Mev/A
Projectile Fragmentation predicted by MC
Z>2 produced fragments approximately have the same velocity of the 12C beam and are collimated in the forward direction
Protons are spread out over a wide range of angle and energy Z=2 fragment are all emitted within 200 of angular aperture
Kinetic energy (MeV/nucl) Emission angle (Deg)
12C + 12C @ 400 MeV/A
FLUKAFLUKA
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The experimental set-up LNSLNS
Interaction Region + Magnet Large-detectors Region
KENTROS: Kinetic ENergy and
Time Resolution Optimized on
Scintillator
START COUNTER
BEAM MONITOR
VERTEX DETECTOR
All detectors of the IR have been tested in Catania at INFN Laboratori Nazionali del Sud with 80 MeV/A 12C or p Cyclotron beams and at the Beam Test Facility of the INFN Frascati National Laboratory with 510 MeV electron beam.
Target
Magnet
TPC MUSIC IVTOF WALL
VertexBmon
Start
The experimental set-up
Vertex Frags emissiondirection
Start start TOF and trigger
TOF WALL frags position & TOF, trigger
Beam mon Beam direction & impact point
Tagger Large frags: position, TOF, dE/dX
TPC MUSIC , dE/dx after bending
LAND2 low angle neutron
Land2
Setup redundancy allows calibration and systematic checks of the reconstructed fragment features: Z, A, , E.
Interaction RegionP Tagger Beam Veto
Start Counter
Standard deviation of the time difference between pairs of Start Counter PMT’s as a function of the run number
Trigger & TOF measurement: 150 micron thick fast scintillator, with radial fibers read-out.
Measured resolution was the order of 150ps
TARGET
BEAM
SC BM
Ptag
VD
scint
ε>99% for ALL the RUNS
Very Stable performance vs run number!
Max variation ~ 5 ps
Beam MonitorDrift chamber: measures the direction and the impact
point of the beam on the target . • 36 sensing wires
• 6 planes perpendicular to the beam•Ar-CO2 80/20 gas mixture @ 2.2 kV
TARGET
BEAM
SC
BMPtag
VD
Beam monitor event display for carbon ions traversing the detector
Beam monitor spatial resolution as a function of the distance from the cell center
Vertex Detector TARGET
BEAM
SC
BM Ptag
VD
Vertex Detector: track all the charged fragment just downstream the target, from 00 to 600.
Based on 4 planes of 2x2 cm2 active area, each made of two MIMOSA 26 silicon pixel detectors, 3mm spaced.
It can measure tracks with an angular resolution of about 0.3 degree.
KENTROS Kinetic ENergy and Time Resolution Optimized on Scintillator
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Detects large angle (50-900) slow protons (He). Measures TOF (expected t=250ps), E (expected E/E = 10%
Kentrosaurus :stegosauride family of late Jurassico.
EJ-200 fast scintillator ( decay time 2.1 ns, 10000 photons/MeV) read by AvanSiD (IRST/FBK) 4x4 mm2 active area SiPMBarrel external : diametero 74 cm, 50 scintillator modules 3,8 cm thick, parallel respect to the beam ; Barrel internal : scintillating fibers , 20 modules ( polar angles measurements). Big Endcap : a disk with internal and external diameter of 28 and 74 cm, 60 trapezoidal scintillator modules, 3.5 cm thick .Small Endcap : a disk with internal and external diameter of 10 and 30 cm, 24 trapezoidal scintillator, 3.5 thick.
KENTROS: proton taggerTARGET
BEAM
SC
BMPtag
VD
ADC counts
HeliumProton
ADC counts
Tim
e (n
s)
HeliumProton
p/He PID on Small Endcap:
no impact position used yet
Matching hits with vertex tracks improve both TOF & dE/dx measurements particle Energy.
VertexBeammonitor
TOF WALL
• Gives arrival time, dE/dx and impinging position of the fragments.
• Two walls made of 96 2x1x110 cm3 scintillators read by two PMTs, grouped in 8 slats unit.
Magnet
TPC TOF WALL
Land2
IR
Q1,t1
Q2,t2
• Calibration run at high statistic with no B field to align with vertex tracking.
• Calibration run with B field sweep with no target at high statistic to calibrate the vertical position
TOF WALL:data vs MC (FLUKA)
The TOFWALL standalone identify fragments
Experimental data are in agreement with MC
Magnet
TPC TOF WALL
Land2
IRTO
F-T tr
ig (n
s)
TOF
(ns)
dE/dx (MeV)dE/dx (MeVx100)
12C 400MeV/u on CDATA
12C 400MeV/u on CMC (FLUKA)
CBBeLiHep CBBeLiHep
Outlook on a ‘mission (im)possible‘
There is an interest in light ions use in hadrontherapy different form 12C
The FIRST detector can easily measure fragmentation cross sections d2/ddE by ions like Helium, Litium or Oxigen
7Li on 12C @250MeV/A
The experimental setup is also designed to be able to measure fragmentation cross section also with heavier ions like Fe @ 1GeV/A, that would be interesting for radioprotection in space. ESA and NASA are also interested in this measures.
The collaboration back up all these options: future largely depends on the GSI interest/possibility to pursue these measurements.
FLUKA MC
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Summary An international collaboration (France, Germany, Italy, Spain) has
been created to measure at GSI the d2/ddE fragmentation cross section of interest for hadrontherapy and space radioprotection
The detector is an evolution of a pre-existing setup, optimized for the detection of fragments with large angular acceptance and with an
accuracy at the few % level
Fragmentation data with 12C already taken in August 2011. Analysis ongoing
In next future the setup could be a facility to measure the fragmentation of light ions (He, Li, O projectiles) and/or of projectiles
(Fe) of interest for space radioprotection
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Perspective‘Health’ research bridging the gap between
science and policy ?
It is a good idea but we still have to improve it…
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Thank you very much for your attention !
eilbronn et al.12C Projectile Energy[MeV/N] Target
4He 100, 180 C, Al, Cu, Pb 12C 100, 180,400 C, Al, Cu, Pb20Ne 100, 180,400 C, Al, Cu, Pb28Si 800 C, Al, Cu, Pb HIMAC by Kurosawa et al.40Ar 400 C, Al, Cu, Pb56Fe 400 C, Al, Cu, Pb126Xe 400 C, Al, Cu, Pb20Ne 337 C, A, Cu and U BEVALAC by Schimmerling et al.93Nb 272 Al, Nb BEVALAC by Heilbronn et al.93Nb 435 Nb4He 155 Al NSRL by H155 Nb4He 160 Pb SREL by Cecil4He 180 C, H2O, steel, Pb
12C 200 H2O GSI by Günzert-Marx et al.12C 400 H2O GSI by Haettner et al.
Courtesy of M. Durante
What we already know: thick target measurement
Tentative & incomplete
list
A lot of integral measurements measurements
are already around.. But very
few for the correct triplet of projectile,target
and energy
What we already know: thin target measurement
Projectile Energy[MeV/N] Target
4He 135 C, Poly, Al, Cu, Pb 12C 135 C, Poly, Al, Cu, Pb Sato et al.
20Ne 135 C, Poly, Al, Cu, Pb 40Ar 95 C, Poly, Al, Cu, Pb
12C 290, 400 C, Cu, Pb 20Ne 400, 600 C, Cu, Pb Iwata et al.
40Ar 400, 560 C, Cu, Pb
4He 230 Li, C, CH2, Al, Cu, Pb 14N 400 Li, C, CH2, Al, Cu, Pb
28Si 60 Li, C, CH2, Al, Cu, Pb Heilbronn et al. 56Fe 500 Li, C, CH2, Al, Cu, Pb
12C 400 C, Poly Toshito et al.
12C 95 PMMA GANIL by Braunn et al.
only with detectors at ~ 0°
Courtesy of M. Durante
Tentative & incomplete
list
A lot of measurements on thin target are
already around.. but not wrt production angle and
energy
Emulsion Chamber: angle okE ~OK, low stat, no corr
angle ok & energy ok
Galactic Cosmic Ray *
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*Francis A. Cucinotta (NASA, Lyndon B. Johnson Space Center), private communication
GCR on Mars*
Dose eq. on EarthEarth: 10 mSv/dDose eq. on MarsMars: 100-200 mSv/d
Dose eq. on MoonMoon: 300-400 mSv/d Dose eq. from GCRGCR: 1 mSv/d
What should we know about 12C fragmentation?Datasets existing, but mainly on thick target or at 0 deg. New measurements now ongoing
or foreseen. The ideal data set should give:Production yelds of Z=0,1,2,3,4,5 fragments
d2/ddE with respect to angle and energy, with large angular acceptance For any 12C energy of interest (50-350 MeV/nucl)
Measurements on thin target of all materials crossed by C beamDetect the correlation between emitted fragments
12C , E
12C , E'
,A,Z
',A',Z'
X,Ex,x,x
Y,Ey,y,y
Not possible a complete DB of measurementsWe need to train nuclear interaction models (MC!!) with the measurements!!
Carbon Ions 12C advantages :
12C disadvantages :
Dose over the Bragg
Peak :p ~ 1-2 %C ~ 15
% Ne ~ 30 %
• More precise energy deposition• Optimal RBE profile - penetration depth position.•Good compromise betwenn RBE and OER• Online PET for depth deposition monitoring
• Production of fragments with higher range vs primary ions• Different biological effectiveness of the fragments•Mitigation and attenuation of the primary beam
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