“El láser ultra-intenso: una esperanza en la solución del ... · “El láser ultra-intenso:...
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“El láser ultra-intenso: una esperanza en la solución del problema energético y el uso
generalizado de los aceleradores de partículas”
Dr. Iván Padrón DíazCEADEN
La Habana, Cuba
Target
Positioner Before each experiment, a positioner precisely centers the target inside
the target chamber and serves as a reference to align the laser beams.
NIF Hohlraum The hohlraum cylinder, which contains the NIF fusion fuel capsule, is
just a few millimeters wide, about the size of a pencil eraser, with beam entrance holes at either end. The fuel capsule is the size of a small pea.
Experimental results :quasi mono energetic spectra
0,0 0,5 1,0 1,5 2,0 2,5
0,0
0,2
0,4
0,6
0,8
1,0
1,2 SimulationExperiment
prot
on c
ount
s [a
.u.]
proton energy [MeV]
Schwoerer, H. et al., Nature, 439 (2006)
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3D Simulations: Laser Piston Acceleration
I = 1023 W/cm2, Target thickness = 1m, Ne
= 5 x 1022 cm-3
COULOMB 09, ICFA workshop, Senigallia, Italia , June 8-12 (2009)
Esirkepov, Bulanov, PRL 2004
Ion beam therapy: Treatment planning
Precision absolute beam positioning better than 1mm Dose control (local) 1%
Dose 40-80 Gray distributed over 10-20 fractions (109-1010 ions per fraction
and few minutes)
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The raisons of a non satisfied medical need
2 2
6
10
2
21
7
1960-1970 1971-1980 1981-1990 1991-2000 2001-2010
protonsions carbone
5 centres protons et2 centres carbone(en projet : 1 centre protons)
7 centres protons (dont 1 au Canada)( en projet : 2 centres protons)
1 centre protons
1 centre protons( en projet : 1 centre protons)
en projet : 1 centre protons
12 centres protons et 1 centre carbone( en projet : 5 centres protons, 1 centre carbone et 4 centres associant protons et carbone)
5 centres protons et2 centres carbone(en projet : 1 centre protons)
7 centres protons (dont 1 au Canada)( en projet : 2 centres protons)
1 centre protons
1 centre protons( en projet : 1 centre protons)
en projet : 1 centre protons
12 centres protons et 1 centre carbone( en projet : 5 centres protons, 1 centre carbone et 4 centres associant protons et carbone)
Market in progress but still limited by the cost and the size of the installation Estimation of the needed protontherapy center in the world (based on the hypothesis that 15% of patients are treated by proton beam) :
In Europe : 300 In USA : 150
-2 protontherapy center in France (Orsay et Nice)
-30 centres in «
modern
»
countries
-Limitation due :–Cost of the installation : 80 à
140 M€–Size of the installation : 1000 to 2000 m²
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Protontherapy center : large & expensive & performant
Costo estimado
200 Millones USD, Pacientes anuales
1000
Where are we now ?
biological effectiveness unknown available energies are high enough to start !!! ion energies are still too low, but promising
development (influencing future laser parameters)
online and offline dosimetry (remember % level) targetry and dedicated (safe) beamline design
PET ScansPositron Emission Tomography, or PET, scanning is an imaging technique that uses radioactive positrons (positively charged particles) to detect subtle changes in the body's metabolism and chemical activities.
There the tracer emits positrons, which collide with electrons, producing gamma rays, that are detected by a ringed-shaped PET scanner and analyzed by a computer to form an image of the target organ's metabolism or other functions.
Human Brain Performing
PET Scanner
Ion energy and conversion efficiency depend on laser energy
Conversion
efficiency
laser-ion
beam
energy:• < 1 J Laser:
0.1 %
• ~ 10 J Laser: 2 -
4 %
(1012-1013
ions)
• ~ 500 J Laser: 15-20 %
Total activity generated by a single laser shot for both 11C and18F as a function of
laser irradiance with pulse energies from 15 to 300 J
Are there enough Protons available?
Layer1 2 3 4
2 nm
5 nm
20 nm
100 nm
Begin of filamentation
Experiments at LULI show no beam degradationup to 100 nm CH coating at the rear of Au foils
PRST-AB, 5, 061301 (2002))
For 26 kJ @ 3 MeV electron Temperature
4 •
1016
Protons
Assuming
40 nm CH (ρ=0.93)
Consistent
with intensity requirement !!!!
bbbbbbbbbbbbb
Nuclear Reactions Triggered by LasersJETI chamber
PW VULCAN target chamber
30 TW LOA laser
UHI10 target chamber at SLIC
Alternative way of producing 225Ac for alpha-immunotherapy ?
2n
p225Ac could be produced through two paths:
226 225
226 225 22515
, 2
( , ) 200 m @14 Mdays
Ra p n Ac
Ra n Ra Ac b eV
Laser induced neutron sources
Big Stationary Neutron Sources Flux [neutrons/cm2s] Traditional Reactor from 107 to 1013 High Flux Research Reactor up to 1015 Accelerator Driven Spallation up to 1014 Compact and Portable Neutron Sources Typical Source Strength
[neutrons/s] Radioactive Neutron Sources 105 to 107 Spontaneous Fission Sources around 1010 Portable Neutron Generators 108 to 1010 Lasers on Solid Targets Reaction(s)
Used Measured Source Strength [neutrons/shot]
Laser Energy [J/shot]
Lancaster 7Li(p,n)7Be 2×108 sr-1 69 Yang natZn(p,xn)Ga ≈ 1010 230 Yang 7Li(p,n)7Be 5×1010 230 Zagar natPb(p,xn)Bi 2×109 400
0 5 10 15 20 25 30 35104
105
106
107
108
109
10 20 30 40
109
1010
1011
1012 measured
Boltzmann fit (kT = 5 MeV)
Prot
ons
(1/M
eV)
Energy (MeV)
235U fission spectrum
Neu
trons
(1/M
eV)
Energy (MeV)
2x109 neutrons
Laser induced X rays and neutron sources
Some General Properties• Compact Table-Top Sources (!)• Forward Directed Beams• Pulsed Operation • Very Short Pulse Durations (!)• High Repetition Rates• Useful Source Strengths
Structural
BiologyNeutrons complement X rays in studying proteins for information of vital interest to the pharmaceutical, agricultural, and biotechnology industries.
The building blocks of DNA direct the synthesis of proteins, whose shape and structure will be determined by neutron scattering.
The power of neutron scattering to detect hydrogen atoms is shown in this image of hydrated carbon monoxide myoglobin. The space-filling stippled structures on the protein stick model are hydrating water molecules.
The superior ability of neutrons to precisely locate hydrogen (or deuterium) atoms-as well as carbon, oxygen, nitrogen, and phosphorus atoms-in macromolecular structures will likely be important to the pharmaceutical industry.
Structural
Biology