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Monoenergetic proton beams accelerated by a radiation pressure driven shock
Charlotte A J Palmer1, N P Dover, I Pogorelsky
1Blackett Laboratory, Imperial College, London SW7 2AZ, United Kingdom.
Physical Review Letters
|January 15, 2011
Summary
Intense infrared lasers can accelerate proton beams from hydrogen gas. This radiation pressure-driven shock produces high-quality proton beams with narrow energy spread and low emittance.
Area of Science:
- Plasma Physics
- Laser-driven Acceleration
- Particle Beams
Background:
- Generating high-quality proton beams is crucial for various scientific applications.
- Laser-driven acceleration offers a promising pathway for compact particle sources.
Purpose of the Study:
- To investigate the acceleration of proton beams using intense infrared lasers.
- To characterize the properties of the generated proton beams.
Main Methods:
- Utilizing an intense infrared laser (λ=10 μm) to irradiate a gaseous hydrogen target.
- Employing optical probing to observe target dynamics.
- Analyzing the energy spread, emittance, and background of the proton beams.
Main Results:
- Achieved acceleration of impurity-free quasimononenergetic proton beams.
- Proton beams exhibited MeV energies with a narrow energy spread (∼4%).
- Recorded low normalized emittance (∼8 nm) and negligible background.
Conclusions:
- The acceleration mechanism is confirmed to be a radiation pressure-driven shock.
- This method provides a viable route for producing high-quality proton beams.
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