Designing zettawatt-equivalent experiments for ZEUS

The Zettawatt-Equivalent Ultrashort pulse laser System (ZEUS) at the University of Michigan is a user facility supported by the National Science Foundation. The name ZEUS refers to the collision of a petawatt (PW) laser pulse with a GeV energy electron beam, producing the equivalent of a “Zettawatt” power laser interaction (1021 W) in the rest frame of the electron beam. The facility aims to enable systematic exploration of strong-field quantum electrodynamics processes by producing synchronized 2.5 PW and 0.5 PW pulses. The ZEUS target area has been designed to enable two collision geometries: one in which the 2.5 PW pulse drives laser wakefield acceleration (LWFA) to generate high-energy electron beams that collide with the 0.5 PW pulse, and another in which the 0.5 PW pulse drives LWFA and electrons collide with the 2.5 PW pulse focused to ultrahigh intensity. This paper describes initial designs and preparations for zettawatt-equivalent experiments at ZEUS.