All-optical bright γ-ray and dense positron source by laser driven plasmas-filled cone

Area of Science:

• Plasma Physics
• Quantum Electrodynamics (QED)
• High-Energy Laser-Matter Interactions

Background:

• Generating high-brightness gamma rays and electron-positron pairs is crucial for fundamental physics research.
• Existing methods often require large-scale facilities or complex setups.

Purpose of the Study:

• To propose and simulate an all-optical scheme for producing bright gamma rays and dense electron-positron pair sources.
• To explore the underlying physical mechanisms of photon and pair production in laser-plasma interactions.

Main Methods:

• Utilizing 2D and 3D Quantum Electrodynamics (QED) particle-in-cell (PIC) simulations.
• Irradiating a near-critical-density plasma-filled aluminum cone with a 10^22 W/cm^2 laser.

Main Results:

• A dense electron bunch is confined by radiation reaction, leading to transverse oscillations.
• Bright gamma rays are produced via nonlinear Compton scattering and Compton backward scattering.
• Abundant electron-positron pairs are generated through the multi-photon Breit-Wheeler process, reaching densities of ~10^27 m^-3.
• 3D simulations confirm a positron yield up to 2 x 10^9.

Conclusions:

• The proposed all-optical scheme offers a compact and efficient method for generating gamma rays and electron-positron pairs.
• This technique opens new avenues for laboratory-based studies in astrophysics and nuclear physics.