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FIRST experiment:
Fragmentation of Ions Relevants for Space and Therapy
Clementina Agodi
Istituto Nazionale di Fisica Nucleare
Laboratori Nazionali del Sud
Catania
11TH International Conference on NUCLEUS NUCLEUS COLLISIONS
May 27-June 1, 2012 San Antonio, TEXAS, USA
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FIRST experiment at GSI
• Introduction
• The FIRST experimental set-up
•
12C
Fragmentation measurements at GSI
• Summary & Perspective
Hadrontherapy Motivation
Light 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 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 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
Production of fragments with
higher range vs primary ions
Dose over the
Bragg Peak :
p ~ 1-2 %
C ~ 15 %
Ne ~ 30 %
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Nuclear fragmentation and Models
• 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/ddE double-differential crosssection are scarce.
X,Ex,x,x
,A,Z
12C
E
,
12C
E'
,
',A',Z'
Y,Ey,y,y
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Space radiation risks assessment
NASA Space Radiation Program Goal:
To live and work safely in space with acceptable risks from radiation
The Space Radiation Environment
Solar particle events (SPE)
about 90% protons, E<1 GeV,
seldom but potentially
dangerous (highdose)events
(generally associated with
Coronal Mass Ejections from
the Sun
Fe
C
Trapped Radiation:
Van Allen belts (electrons,
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)
C
Fe
GCR reach earth rarely, but become relevant for exposure
into interplanetary flights, that are the NASA future plans
*Francis A. Cucinotta (NASA, Lyndon B. Johnson Space Center), private communication
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Nuclear fragmentation measurements in
Hadrontherapy and Space radiation risks assessment
Hadrontherapy




Spatial vehicles shieldings
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
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
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Fragmentation of Ions Relevants for Space and Therapy


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
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Fragmentation measurements at GSI
FIRST al GSI ( 1-14 August 2011)
Fragmentation of Ions Relevant for Space and Therapy
The 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
 Collected around 2 ml of events
12C+12C
@400 Mev/A
12C+197Au
@400 Mev/A
Projectile Fragmentation predicted by MC
12C
+ 12C @ 400 MeV/A
FLUKA
Kinetic energy (MeV/nucl)

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FLUKA
Emission angle (Deg)
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
The experimental set-up
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START COUNTER
VERTEX
DETECTOR
BEAM MONITOR
KENTROS:
Kinetic ENergy and
Time Resolution
Optimized on
Scintillator
Interaction Region + Magnet Large-detectors Region
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.
The experimental set-up
Interaction Region
TOF WALL
TPC MUSIC IV
Magnet
Beam Veto
P Tagger
Start
Target
Bmon
Vertex
Land2
Vertex
Start
Setup redundancy  allows
calibration and systematic
checks of the reconstructed
fragment features: Z, A, ,
E.
Frags emission direction
start TOF and trigger
TOF WALL
Beam mon
Tagger
Beam direction & impact point
Large
TPC MUSIC
LAND2
frags position & TOF, trigger
frags: position, TOF, dE/dX
, dE/dx
low angle neutron
after bending
SC
Start Counter
BM
TARGET
VD
BEAM
Ptag
ε>99% for ALL the RUNS
scint
Very Stable
performance vs run
number!
Max variation ~ 5 ps
Trigger & TOF measurement: 150 micron thick
fast scintillator, with radial fibers read-out.
Measured resolution was the order of 150ps
Standard deviation of the time difference between pairs of Start
Counter PMT’s as a function of the run number
SC
Beam Monitor
BEAM
Drift 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
Beam monitor event display for carbon
ions traversing the detector
Beam monitor spatial
resolution as a function of the
distance from the cell center
TARGET
BM
Ptag
VD
Vertex Detector
SC
Vertex Detector: track all the charged fragment BEAM
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.
TARGET
BM
Ptag
VD
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KENTROS
Kinetic ENergy and Time Resolution Optimized on Scintillator
Detects large angle (50900) slow protons (He).
Measures TOF
(expected t=250ps),
DE (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
SiPM
Barrel 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.
TARGET
SC
KENTROS: proton tagger
Time (ns)
Matching hits with vertex tracks improve both TOF &
dE/dx measurements  particle Energy.
BEAM
BM
Ptag
Proton
Helium
ADC counts
Beam
monitor
Proton
Helium
p/He PID on Small
Endcap:
no impact position
used yet
ADC counts
Vertex
VD
TPC
TOF WALL
TOF
WALL
IR
Magnet
Land2
• 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.
Q1,t1
• 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
Q2,t2 position
TOF
WALL
TPC
IR
TOF WALL:
data vs MC (FLUKA)
Land2
Magnet
The TOFWALL standalone identify fragments
12C
p He
Li
400MeV/u on C
DATA
Be
B
C
dE/dx (MeV)
12C
TOF (ns)
TOF-Ttrig (ns)
Experimental data are in agreement with MC
p He Li
400MeV/u on C
MC (FLUKA)
Be
B
C
dE/dx (MeVx100)
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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/ddE by ions like Helium,
Litium or Oxigen
FLUKA MC
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.
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Summary
 An international collaboration (France, Germany, Italy, Spain) has
been created to measure at GSI the d2/ddE 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
It is a good idea but we still have to improve it…
Thank you very much for your
attention !
What we already know:
thick target measurement
eilbronn et al.
12C
Projectile
4He
12C
20Ne
28Si
40Ar
56Fe
126Xe
20Ne
93Nb
93Nb
4He
4He
4He
12C
12C
Energy[MeV/N] Target
A lot of integral
measurements
measurements are
already around..
But very few for
the correct triplet
of
projectile,target
and energy
100, 180
C, Al, Cu, Pb
100, 180,400 C, Al, Cu, Pb
100, 180,400 C, Al, Cu, Pb
800
C, Al, Cu, Pb
HIMAC by Kurosawa et al.
400
C, Al, Cu, Pb
400
C, Al, Cu, Pb
400
C, Al, Cu, Pb
337
C, A, Cu and U
BEVALAC by Schimmerling et al.
272
Al, Nb
BEVALAC by Heilbronn et al.
435
Nb
155
Al
NSRL by H155
Nb
Tentative &
160
Pb
SREL by Cecil
180
C, H2O, steel, Pb
incomplete list
200
400
H2O
H2O
GSI by Günzert-Marx et al.
GSI by Haettner et al.
Courtesy of M. Durante
What we already know: A lot of measurements on
thin target measurement thin target are already
 Projectile Energy[MeV/N]

 4He
12C




20Ne


135
20Ne
135
95
40Ar
12C



28Si
135
C, Poly, Al, Cu, Pb
C, Poly, Al, Cu, Pb
Sato et
al.
C, Poly, Al, Cu, Pb
C, Poly, Al, Cu, Pb
290, 400
400, 600
al.
40Ar
400, 560
4He
230
400
14N
60
56Fe
500
Courtesy
 12Cof M. Durante 400
Target
around.. but not wrt
production angle and
energy
C, Cu, Pb
C, Cu, Pb
C, Cu, Pb
Iwata et
Tentative &
incomplete list
only with
detectors
at ~ 0°
Li, C, CH2, Al, Cu, Pb
Li, C, CH2, Al, Cu, Pb
Li, C, CH2, Al, Cu, Pb
Heilbronn
Emulsion Chamber: angle o
et al.
E ~OK, low stat, no corr
Li, C, CH2, Al, Cu, Pb

angle ok & energy
C, Poly
Toshito et al.
ok
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Galactic Cosmic Ray *
GCR on Mars*
Dose eq. on Moon: 300-400 mSv/d
Dose eq. from GCR: 1 mSv/d
Dose eq. on Mars: 100-200 mSv/d
Dose eq. on Earth: 10 mSv/d
*Francis A. Cucinotta (NASA, Lyndon B. Johnson Space Center), private communication
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/ddE 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 beam
 Detect the correlation between emitted fragments
X,Ex,x,x
,A,
Z
12C
E
,
12C
E'
,
',A',Z
Y,Ey,y,y
'
Not possible a
complete DB of
measurements
We need to train
nuclear interaction
models (MC!!) with
the measurements!!
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Carbon Ions

12C
advantages :
• More
precise energy deposition
• Optimal RBE profile - penetration
depth position.
•Good compromise betwenn RBE and
OER
• Online PET for depth deposition
monitoring

12C
• Production
disadvantages :
of fragments with higher range vs
primary ions
• 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 %