Terry Kammash - NASA's Institute for Advanced Concepts
Terry Kammash - NASA's Institute for Advanced Concepts Terry Kammash - NASA's Institute for Advanced Concepts
Future Laser DevelopmentOscillatorCleaner(10 6 contrast)RegenerativeAmplifier4-passAmplifier2-passAmplifierHigh-PowerAmplifierEnergy Pulse width RepetitionRate1 nJ 10-15 fs 80 Mhz1 mJ 15 fs 10 Hz100 mJ 350 ps 10 Hz1-1.5 J7-10 J350 psCurrent Hercules350 ps10 Hz0.1 Hz50 J 350ps 0.1 HzCompressedOutputN/AN/AN/A20-30 TW@ 25 fs100-200 TW@ 25-40 fs1 PW @ 30-40 fs
Proton Acceleration Summary• Simulation and experiment support proton acceleration at thelaser-irradiated side of the target of a 4 MeV beam, on the backof the underdense plasma under these conditions.• And a 12 MeV beam from the rear-surface of Al due torecirculation sheath enhancement.• Beam spectrum has bands of energies due to “ion fronts.”• Beam profile smoothes out as initial target conductivityincreases.• Filamentation and structures similar to the electron simulationby Gremillet et. al have been observed.• Demonstrated beam profile modification with modest geometry,and enhancement of number at the maximum energy achievedby initial target geometry and surface conditions• CR-39 response is highly non-linear when scanned optically.• By using a highly absorptive material we have increased thenumber of maximum energy protons without sacrificing beamquality. No imprint of LB on beam profile, unlike Roth et. al• New 30 fs laser has produced 10 21 W/cm 2 on target in a 1 micronspot, expect high efficiency acceleration
- Page 1 and 2: Ultrafast Laser-DrivenPlasma for Sp
- Page 3 and 4: Front Surface Deuteron Acceleration
- Page 5 and 6: Material Effect on ProtonProduction
- Page 7 and 8: (a) 4 µm, (b) 12.5 µm, (c) 25 µm
- Page 9 and 10: Magnetic Field from Simulation vs.P
- Page 11 and 12: Protons From Front Surface1614Maxim
- Page 13 and 14: Deuteron AccelerationDeuteron coati
- Page 15 and 16: Peak Proton Energyvs. Spot Size6000
- Page 17 and 18: Spot Size Comparison120Total Intens
- Page 19 and 20: Plume Evolution in 1 Torr H 2Ambien
- Page 21 and 22: Target GeometryWire orientation:~10
- Page 23: Proton RadiographyThin Film TargetT
- Page 27 and 28: Physics ContinuedEnergy conservatio
- Page 29 and 30: ContinuedThe Ion EnergyE i =ZE b =Z
- Page 31 and 32: Two Asymptotic Regimes forIon Accel
- Page 33 and 34: Relationship Between Ion Energy,Las
- Page 35 and 36: An ExampleI=10 21 W/cm 2η=0.10R=2.
- Page 37 and 38: Plasma Expansion in VacuumIon accel
- Page 39 and 40: Accomplishments Thus Far1. Generate
- Page 41 and 42: Accomplishments Thus Far4. Experime
Proton Acceleration Summary• Simulation and experiment support proton acceleration at thelaser-irradiated side of the target of a 4 MeV beam, on the backof the underdense plasma under these conditions.• And a 12 MeV beam from the rear-surface of Al due torecirculation sheath enhancement.• Beam spectrum has bands of energies due to “ion fronts.”• Beam profile smoothes out as initial target conductivityincreases.• Filamentation and structures similar to the electron simulationby Gremillet et. al have been observed.• Demonstrated beam profile modification with modest geometry,and enhancement of number at the maximum energy achievedby initial target geometry and surface conditions• CR-39 response is highly non-linear when scanned optically.• By using a highly absorptive material we have increased thenumber of maximum energy protons without sacrificing beamquality. No imprint of LB on beam profile, unlike Roth et. al• New 30 fs laser has produced 10 21 W/cm 2 on target in a 1 micronspot, expect high efficiency acceleration