UCI, Irvine, California, USA
LLNL, Livermore, California, USA
The mean energy, energy spread and divergence of the electron beam can be deduced from laser-Compton scattered X-rays filtered by a material whose K-edge is near the energy of the X-rays. This technique, combined with a spot size measurement of the beam, can be used to measure the emittance of electron bunches, and can be especially useful in LWFA experiments where conventional methods are unavailable. The effects of the electron beam parameters on X-ray absorption images are discussed, along with experimental demonstrations of the technique using the Compact Laser-Compton X-ray Source at LLNL.
UCI, Irvine, California, USA
LLNL, Livermore, California, USA
Compton scattering of laser photons by a relativistic electron beam produces monoenergetic, tunable and small source size X-rays similar to synchrotron light sources in a very compact setting, due to the shorter undulator period of lasers. These X-ray sources can bring to every hospitals advanced radiology and radiotherapy that are currently only being conducted at synchrotron facilities. Few examples include phase contrast imaging utilizing the micron-scale source size, K-edge subtraction imaging from two monoenergetic X-rays at different energies and radiation therapy using radiosensitization of high-Z nanoparticles. At LLNL, 30 keV X-rays have been generated from the 30 MeV X-band linac, and the X-rays have been characterized and agree with the modeling very well. This source is being used to study the feasibility of aforementioned medical applications. Experimental setup of K-edge subtraction of contrast agents are presented, demonstrating the low-dose, high-contrast imaging potential of the light source. Plans to study enhanced radiotherapy using Gold nanoparticles with the upgrade of the machine to higher energies are discussed.
