High-brilliance, high-flux compact inverse Compton light source

Abstract

The Old Dominion University Compact Light Source (ODU CLS) design concept is presented—a compact Inverse Compton Light Source (ICLS) with flux and brilliance orders of magnitude beyond conventional laboratory-scale sources and greater than other compact ICLS designs. This concept utilizes the physics of inverse Compton scattering of an extremely low emittance electron beam by a laser pulse of rms length of approximately two-thirds of a picosecond (2/3 ps). The accelerator is composed of a superconducting radio frequency (SRF) reentrant gun followed by four double-spoke SRF cavities. After the linac are three quadrupole magnets to focus the electron beam to the interaction point (IP). The distance from cathode surface to IP is less than 6 m, with the cathode producing electron bunches with a bunch charge of 10 pC and a few picoseconds in length. The incident laser has 1 MW circulating power, a 1 micron wavelength, and a spot size of 3.2 microns at the IP. The repetition rate of this source is 100 MHz, in order to achieve a high flux despite the low bunch charge. The anticipated x-ray source parameters include an energy of 12 keV, with a total flux of 2.2×10^{13} ph/s, the flux into a 0.1% bandwidth of 3.3×10^{10} ph/(s 0.1%BW), and the average brilliance of 3.4×10^{14} ph/(s mm^{2} mrad^{2} 0.1%BW).