Standard methods of measuring the transverse beam profile are not adaptable for sufficiently high-intensity beams. Therefore, the development of non-invasive techniques for extracting beam parameters is necessary. Here we present experimental progress on developing a transverse profile diagnostic that reconstructs beam parameters based on images of an ion distribution generated by beam-induced ionization. Laser-based ionization is used as an initial step to validate the electrostatic column focusing characteristics, and different modalities, including velocity map imaging. This paper focuses on measurements of the ion imaging performance, as well as the dependence of Ion intensity on gas density and incident beam current for low-energy electron beams (<10 MeV).

The FAST Injector at Fermilab has been the focus of a number of recent experimental efforts as 1) the driver of a novel FEL experiment, 2) as the injector for IOTA, and 3) as a test-bed for novel machine learning algorithms to reconstruct phase space measurements. Here we present our recent work to simulate the FAST injector and perform realistic comparisons of simulated beam distributions to measured beam distributions using a multi-slit emittance diagnostic. We also present studies on using laser pulse stacking to shape the beam distribution for creating optimal current distributions for FEL experiments.

Standard methods of measuring the transverse beam profile are not adaptable for sufficiently high-intensity beams. Therefore, the development of non-invasive techniques for extracting beam parameters is necessary. Here we present experimental progress on developing a transverse profile diagnostic that reconstructs beam parameters based on images of an ion distribution generated by beam-induced ionization. Laser-based ionization is used as an initial step to validate the electrostatic column focusing characteristics, and different modalities, including velocity map imaging. This paper focuses on measurements of the ion imaging performance, as well as the dependence of Ion intensity on gas density and incident beam current for low-energy electron beams (<10 MeV).