Plasma Channel Modulation in Capillary Discharges for Particle Accelerators

Next generation accelerators demand sophisticated beam sources to reach ultra-low emittances at large accelerating gradients. Capillary discharge plasmas can address these challenges by improving the energy and quality of laser-plasma accelerated electrons 1 . Significant improvements to the guiding properties of these structures can be achieved through the spatiotemporal manipulation of plasma channel density via laser heating 2 , fill density modulation, and radial tapering. We present 2D simulations of capillary discharge plasmas using FLASH, a publicly-available multi-physics code with specialized support for critical transport processes and magnetohydrodynamic evolution 3 . We demonstrate the application of laser energy deposition to model channel formation for guiding intense laser pulses. We consider parametric variations in heater laser intensity and timing to optimize the matched spot size. Lastly, we examine the control and tapering of density profiles through the tailoring of capillary geometry and gas flow.