Aerosol beam profile manipulation to improve particle density outside the aerodynamic lens stack*

Charged droplets can be used to manipulate the trajectory of an aerosolized particle beam outside the aerodynamic lens stack. In this simulation study, the Uppsala injector particle beam trajectory is optimized for improving the SNR of the diffraction pattern for XFEL single-particle imaging. Data of droplet size, frequency, position, and velocity distribution are ascertained in Bielecki et. al., 2019 and Hankte et. al., 2018 using Rayleigh scattering microscopy. The aerosolized particle trajectories are integrated from its forces and particle count is aggregated on a bin to generate a discrete map of the particle density profile. This profile is optimized by manipulating an electric field outside the accelerating nozzle of the Aerodynamic Lens Stack (ALS). As such the acceleration of the particles is a function of aerodynamic drag ascertained from Bielecki et. al., 2019, electric field forces from the charged plate are computed using finite element methods and N-Body Coulomb repulsion is computed using Barnes-hut approximation. Under such conditions, the simulation indicates the slowdown of particles increases the particle density at a point dependent on the strength of the electric field by almost 10x in simulation.