A compact Compton scattering X-ray source for cancer detection, diagnosis, and treatment

A compact, tunable, high brightness, and monoenergetic source of x-rays is under development to improve the detection, diagnosis, and treatment of cancer. X-rays will be efficiently produced when a dense relativistic electron bunch collides with an intense laser pulse via Compton scattering. Preliminary experiments have successfully demonstrated the production of the high quality electron beams required for use in a Compton x-ray device. A proof-of-principle facility has been designed and is currently under construction to produce Compton x-rays tunable from 15 keV to 120 keV. This facility utilizes low emittance (<1 pi mm-mrad) and high peak current (>500 Ampere) electron beams produced using a novel high frequency photoinjector operating at X-band (11.424 GHz) and a compact terawatt peak power laser system. Sufficient x-ray production efficiency is predicted with small enough average powers that scaling the device to a repetition rate of 1 kHz will allow sufficient average dose rates to perform medical imaging and treatment procedures in a hospital setting. This clinical device will be compact due to the high accelerating gradients which can be achieved at X-band in linear accelerators (100 MV/m) together with the efficient and economical generation of intense laser pulses using a combination of diode-pumped solid-state lasers combined with chirped-pulse amplification of ultrashort (<50 fs) laser pulses.; Combined with recent advances in molecular oncology, the Compton x-ray source will be able to specifically locate cancerous cells via a combination of high resolution, high contrast imaging (made possible by the inherent small source size and high brightness of the Compton x-rays) and in-vivo x-ray absorption spectroscopy. Targeted treatment of cancer will be possible by combining selective contrast agents with monochromatic x-rays tuned to absorption peaks to trigger localized cell damage.