K. E. Deitrick | Searcharxiv

arXiv2026

White Paper on a Novel FFA-Based CEBAF Upgrade to 22 GeV

We present a conceptual design for a cost-effective upgrade of the Continuous Electron Beam Accelerator Facility (CEBAF) to 22 GeV using non-scaling fixed-field alternating-gradient (FFA) arcs built from Halbach-style permanent magnets. Building on the eight-pass energy-recovery demonstration at the Cornell--BNL CBETA test accelerator, the design replaces the highest-energy recirculation arcs with a pair of FFA arcs that simultaneously transport six passes spanning a factor-of-two momentum range. We describe the machine layout; including the injector, recirculating linacs, spreaders and recombiners, FFA arcs, splitters, transition and extraction regions; together with beam-dynamics validation studies covering emittance growth, synchrotron-radiation-driven depolarization, and orbit correction, and we summarize permanent-magnet design, prototyping, and radiation-resiliency results. This white paper documents the accelerator physics underpinning a staged path to 22 GeV that preserves CEBAF's multi-hall, high-luminosity, polarized-beam capabilities.

physics.acc-ph↗

arXiv2018

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

A compact Inverse Compton Light Source (ICLS) design is presented, with flux and brilliance orders of magnitude beyond conventional laboratory-scale sources and other compact ICLS designs. This design 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 radiofrequency (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 meters, 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 $1.4\times10^{14}$ ph/s, the flux into a 0.1% bandwidth of $2.1\times10^{11}$ ph/(s-0.1%BW), and the average brilliance of $2.2\times10^{15}$ ph/(s-mm$^2$-mrad$^2$-0.1%BW).

physics.acc-ph↗