Ionization states for the multipetawatt laser-QED regime

Area of Science:

• Plasma Physics
• High-Intensity Laser-Matter Interactions

Background:

• Multipetawatt laser facilities are advancing laser-plasma interaction physics.
• Radiation reaction processes are critical for energy absorption and transport in these interactions.
• Accurate in situ measurement of focused laser intensity is essential for quantifying these effects.

Purpose of the Study:

• To propose and validate a novel method for measuring focused laser intensity in situ.
• To implement and compare field ionization rates in particle-in-cell simulations.
• To assess the impact of simulation dimensionality on accuracy.

Main Methods:

• Utilizing xenon gas ionization at low pressure to measure focused laser intensity.
• Implementing field ionization rates from established literature into the SMILEI particle-in-cell code.
• Conducting one- and two-dimensional simulations to compare results.

Main Results:

• Simulations successfully reproduced xenon charge states using implemented ionization rates.
• Increasing simulation dimensionality did not introduce significant visible differences in results.
• The proposed method provides a reliable way to verify laser intensity on target.

Conclusions:

• Xenon gas ionization offers a viable in situ diagnostic for focused laser intensity.
• Particle-in-cell simulations with validated ionization rates are effective tools for this application.
• This technique is vital for advancing research in high-intensity laser-plasma physics.