Terahertz-driven positron acceleration assisted by ultra-intense lasers.

Area of Science:

• Plasma Physics
• Particle Acceleration
• Quantum Electrodynamics

Background:

• Energetic positron generation is crucial for applications in medical, high energy, astrophysics, and nuclear physics.
• Compact positron sources face challenges like beam dispersion, dephasing, and instability.

Purpose of the Study:

• To propose a novel scheme for all-optical generation and acceleration of electron-positron pairs using terahertz (THz) fields.
• To address limitations of current compact positron sources.

Main Methods:

• Nanocoulomb-scale electrons are accelerated to 2.5 GeV in a wakefield.
• Energetic electrons generate THz radiation by interacting with an aluminum foil.
• Electron-positron pairs are generated via gamma photon production from electron-photon interactions.

Main Results:

• Positrons are efficiently accelerated to 800 MeV by the THz field's longitudinal and transverse fields.
• Achieved a peak beam brilliance of 2.26 × 10^12 s^-1 mm^-2 mrad^-2 eV^-1.
• Demonstrated a viable method for producing high-quality positron beams.

Conclusions:

• The proposed scheme offers a promising solution for compact, high-brightness positron sources.
• This method has potential applications for PW-class laser facilities and GeV electron beamlines.
• The efficient acceleration and high brilliance of positrons open new avenues for scientific research.