High-Flux Neutron Generator Based on Laser-Driven Collisionless Shock Acceleration.

Area of Science:

• Plasma Physics
• Nuclear Fusion
• Particle Acceleration

Background:

• Traditional neutron sources often face limitations in flux and purity.
• Laser-driven acceleration techniques offer novel pathways for compact neutron generation.
• Collisionless Shock Acceleration (CSA) presents an alternative to Target Normal Sheath Acceleration (TNSA).

Purpose of the Study:

• To propose and experimentally verify a novel compact high-flux neutron generator.
• To investigate the advantages of CSA over TNSA for deuteron acceleration and neutron production.
• To demonstrate a significant increase in neutron yield using the CSA method.

Main Methods:

• Utilizing a pitcher-catcher configuration for laser-driven collisionless shock acceleration.
• Experimentally measuring deuteron energy spectra and forward neutron flux.
• Employing self-consistent simulations to validate experimental results and predict performance at higher laser intensities.

Main Results:

• Observed a characteristic CSA plateau in the deuteron energy spectrum (2–6 MeV).
• Achieved a forward neutron flux of 6.6×10^7 n/sr from a LiF catcher target.
• Demonstrated an order of magnitude higher neutron yield compared to the TNSA method at 10^19 W/cm^2 laser intensity.

Conclusions:

• CSA is a highly effective mechanism for producing high-flux, high-energy deuterons, leading to enhanced neutron yields.
• The proposed CSA-based neutron generator shows significant potential for compact, high-performance neutron sources.
• Simulations predict achievable neutron yields up to 5×10^10 n/sr at higher laser intensities (10^21 W/cm^2).