Monoenergetic Proton Beams from Laser Driven Shocks Dan Haberberger Neptune Laboratory, Department of Electrical Engineering, UCLA In collaboration with: ergei Tochitsky, Chao Gong, Warren Mori, Chan Joshi Neptune Laboratory, Department of Electrical Engineering, UCLA Frederico Fiuza, Luis Silva
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Monoenergetic Proton Beams from Laser Driven Shocks
Monoenergetic Proton Beams from Laser Driven Shocks. Dan Haberberger Neptune Laboratory, Department of Electrical Engineering, UCLA. In collaboration with: Sergei Tochitsky , Chao Gong, Warren Mori, Chan Joshi Neptune Laboratory, Department of Electrical Engineering, UCLA - PowerPoint PPT Presentation
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Monoenergetic Proton Beams from Laser Driven
Shocks
Dan HaberbergerNeptune Laboratory, Department of Electrical Engineering, UCLA
In collaboration with:Sergei Tochitsky, Chao Gong, Warren Mori, Chan Joshi
Neptune Laboratory, Department of Electrical Engineering, UCLA
Frederico Fiuza, Luis SilvaInstituto Superior Technico, Lisbon, Portugal
Outline
AAC (Jun 2012)Neptune Laboratory
• Applications of Laser Driven Ion Acceleration (LDIA) : Hadron cancer therapy• Localized energy deposition : Bragg Peak• Therapy centers : conventional accelerators vs. lasers• Ion source requirements
• Collisionless Shock Wave Acceleration (SWA) of protons• 1D OSIRIS Simulations• Laser driven case
• UCLA proton acceleration experiment : CO2 laser and a H2 gas jet target• Results : Spectra, emittance• Interferometry : Plasma density profile
• 2D OSIRIS simulations• Modeling the experiment• Scaling to higher power lasers• Using 1µm laser systems
• Conclusion
Laser Driven Ion Beam ApplicationsProbing of strong electric fields in dense plasma on the picosecond timescale
– ~1μm resolution, 5-20MeV– Borghesi, Phys. Plasmas (2002)• 50μm Ta wire• Imaging with 6-7MeV protons
-15ps -5ps 5ps
VULCAN Laser, 20J, 1019W/cm2
Hadron Cancer Therapy– 250MeV, 109-1010 protons/s– ΔE/E ≤ 5%
Fast Ignition– 15-23MeV– <20ps– Eff = 10%
Picosecond injectors for conventional accelerators– 1-10MeV, <.004 mm.mrad, <10-4 eV.s [Cowan, Phys. Rev. Lett. (2004)]
AAC (Jun 2012)Neptune Laboratory
Markus RothWG6 : Tuesday 1:30
Energy Deposition : Ions vs. Photons
AAC (Jun 2012)Neptune Laboratory
Bragg Peak for ions results in localized energy deposition
Multi-beam Localization
Radiation dose relative to peak (100%)
Simulations of Irradiating the Human Skull
GSI Helmholtz Centre for Heavy Ion Research in Darmstadt http://www.weltderphysik.de/gebiet/leben/tumortherapie/warum-schwerionen/
Goal Cost : 10-20 million USDTable top laser system (developing)Transportation : MirrorsOnly has focusing magnet Gantry : small, protons generated in direction of patient
M. Murakami, et al., AIP Conf. Proc. 1024 (2008) 275, doi:10.1063/1.2958203
AAC (Jun 2012)Neptune Laboratory
Proton Beam Requirements
Radiation Beam Requirements
2 Gray in 1 liter tumor in a few minutes-Translates to 1010 protons per second
Proton energies in range of 250 MeV
Energy Spread of ~5%
Focusability, Energy Accuracy, Energy Variability, Dose Accuracy, etc.
Lasers can accelerate up to 1012 protons in a single shot
Worlds most powerful lasers have produced 75 MeV protons
Vast majority of beams have continuous energy spread
Future Work
Laser Driven Ion Acceleration (LDIA)
AAC (Jun 2012)Neptune Laboratory
Dose
Energy
EnergySpread
What is a Shock Wave?
Subsonic Sonic Supersonic
A disturbance that travels at supersonic speeds through a medium
• At supersonic speeds, pressure will build at the front of a disturbance forming a shock
• Characterized by a rapid change in pressure (density and/or temperature) of the medium
In a plasma, a shock wave is characterized by a propagating electric field at speeds useful for ion acceleration (Vsh > 0.01c)
AAC (Jun 2012)Neptune Laboratory
1D OSIRIS Simulations
Plasma 1ne1
Te
Cold Ions
Plasma 2ne2
Te
Cold Ions
In Plasmas, the driver is a potential or electric field
Plasma 1ne1 = ne2
Te1
Cold Ions
Plasma 2ne1 = ne2
Te1
Cold Ions
Expansion Shocks Driven Shocks
Ambipolar electric field of Plasma 1 is driven into
Plasma 2
Initial drift causes overlap; overlap causes local density
increase and again ambipolar electric field is driven into the
ConclusionsLaser-driven, electrostatic, collisionless shocks in overdense plasmas
produce monoenergetic protons at high energies• Protons accelerated to 15-22 MeV (at IL ~ 4x1016 W/cm2)• Energy spreads as low as 1% (FWHM)• Emittances as low as 2x4 mm·mrad• Interferometry uncovers unique plasma profile• Plasma simulations elucidate shock wave acceleration of
protons through the backside of the plasma
AAC (Jun 2012)Neptune Laboratory
Step towards achieving 200-300 MeV protons needed for cancer therapy
• Simulations show scaling to ~300 MeV with a laser ao = 15
• Proposed method of exploding foil target for 1µm laser systems
Supporting Simulated Interferogram
Measured Plasma Profile
Simulated Plasma Profile
-600 -400 -200 0 200 4000
1
2
3
4
X-Distance (m)
Plas
ma
Den
sity
(1019
cm-3
)
AAC (Jun 2012)Neptune Laboratory
1μm Nd:GlassCPA System
10μm TEA MasterOscillator
8atm Regenerative
Amplifier2.5atmLarge ApertureFinal Amplifier
3ps, 3mJ
500ns30mJ 3ps
~nJ
3ps4mJ3ps
350mJ
3ps 100J
CS2 Kerr Cell
Low Pressure CO
2 Amplifier
Neptune CO2 MOPA Laser System
AAC (Jun 2012)Neptune Laboratory
1μm Glass CPA System
1μm GlassMaster
Oscillator
1μm GlassRegenerative
Amplifier
Grating
Grating
Grating
Stretcher
Compressor
500fs100mW
~1ns70mW
~1ns4mJ
3ps3mJ
5Hz
110MHz
CS2 Kerr SwitchingCS2 Kerr CellPolarizer Analyzer1µm from CPA
10µm from MO
10µm1µm3ps 500ns
30mJ1mJ3ps1nJ
10µm• I90°(1µm) = 25 GW/cm2
• Signal-to-background contrast = 105
10µm Seed Production
AAC (Jun 2012)Neptune Laboratory
100Jwo = 6.5cm
I = 30-140 GW/cm2
P = 1-15 TW
• Pressure : 2.5atm• Δνpressure = 14GHz• go = 2.6%/cm