X-ray analysis methods for sources from self-modulated laser wakefield acceleration driven by picosecond lasers.

Area of Science:

• Plasma Physics
• X-ray Spectroscopy
• Laser-Driven Acceleration

Background:

• Laser plasma accelerators (LPAs) produce broadband X-ray sources.
• Accurate characterization of X-ray spectra and photon flux is essential for understanding LPA physics.
• Existing methods have limitations in covering the broad energy range and ensuring confidence.

Purpose of the Study:

• To develop and validate versatile methods for analyzing X-ray energy spectra and photon flux from picosecond laser-driven LPA experiments.
• To combine multiple analysis techniques for improved confidence and accuracy in X-ray measurements.
• To characterize and measure X-ray spectra from different emission mechanisms.

Main Methods:

• Development of a versatile analysis suite combining forward fit, Ross pair, and differential average transmission analysis.
• Application of methods to three diagnostics: filter wheel (<40 keV), stacked image plate spectrometer (35-100 keV), and step wedge (60-1000 keV).
• Characterization using laser-driven bremsstrahlung X-rays and measurement of betatron, inverse Compton scattering, and bremsstrahlung X-ray mechanisms.

Main Results:

• Successful characterization of analysis methods using laser-driven bremsstrahlung X-rays.
• Measurement of X-ray energy spectra from 10 keV to 1 MeV.
• Achieved peak flux exceeding 10^10 photons/keV/Sr for broadband X-ray sources.

Conclusions:

• The combined analysis methods provide a robust and accurate tool for measuring broadband X-ray sources from LPAs.
• The developed methods enhance confidence in characterizing X-ray spectra across a wide energy range (keV to MeV).
• This work supports advancements in laser-driven particle acceleration and X-ray science.