Progress Report on the Commissioning of the ZEUS Facility*

The Zettawatt Equivalent Ultrashort Pulse Laser System (ZEUS) is a user facility funded by the National Science Foundation and located at the University of Michigan. ZEUS consists of a repetitive dual-beamline 3 PW laser system, a programmable multi-nanosecond pulse driver capable of delivering 100 J of energy, and three experimental areas with radiation shielding. It offers unique capabilities for studying fields such as nonlinear quantum electrodynamics, relativistic plasmas, particle acceleration, extreme laboratory astrophysics, and nuclear photonics. Access to the ZEUS facility is granted by an independent review panel based on the scientific merit of the proposals submitted. During the 2024 fiscal year, seven user experiments, each lasting one month, were conducted on ZEUS. An additional eight experiments are scheduled for 2025. This presentation will provide an update on the progress of the ZEUS facility's performance, including the laser, target areas, and radiation shielding. It will also discuss the results of the initial commissioning experiment on laser wakefield electron acceleration and betatron radiation generation at the 1 PW level.