Sub-MeV tunably polarized X-ray production with laser Thomson backscattering

Area of Science:

• Physics
• Accelerator Science
• Photonics

Background:

• Generation of polarized X-rays is crucial for various scientific applications.
• Thomson backscattering offers a method for producing high-energy photons.
• Sub-MeV X-ray sources are valuable for advanced imaging and research.

Purpose of the Study:

• To generate unique polarized X-rays in the sub-MeV energy region.
• To characterize the properties of the generated X-ray beam, including energy and polarization.
• To demonstrate the utility of these X-rays for imaging applications.

Main Methods:

• Utilized Thomson backscattering of a Nd:YAG laser (1064 nm) with 150 MeV electrons from a microtron accelerator.
• Measured X-ray photon energy and total energy using an imaging plate and LYSO scintillator.
• Determined angular divergence with an imaging plate and confirmed polarization via Compton scattering.

Main Results:

• Successfully generated polarized X-rays with a maximum energy of approximately 400 keV.
• Measured the total energy and angular divergence of the backscattered X-ray pulse.
• Confirmed X-ray beam polarization aligned with the laser polarization direction.

Conclusions:

• The Thomson backscattering method effectively produces polarized sub-MeV X-rays.
• The generated X-rays possess characteristics suitable for advanced applications.
• Demonstrated successful imaging of a lead-shielded object, highlighting the practical utility of this X-ray source.