The U.S. National Science Foundation has awarded $4.5 million to a six-institution program developing the precision instruments and computer models needed to measure what the world's most powerful lasers actually do. The program, officially titled Diagnostics for Extreme-LIGHT or DELIGHT for short, is led by University of Nevada, Reno physicist Thomas White, the JT Endowed Professor in Physics.

Multi-petawatt lasers compress light energy into an extraordinarily brief burst, focusing it to a spot just a few millionths of a meter across to generate the highest intensity light on the planet. For a fraction of a trillionth of a second, this hyper-concentrated energy recreates the extreme conditions found inside stars and giant planets, as well as the intense electromagnetic fields present in the early universe approaching the Big Bang. Capturing precise data from an environment this violent, short-lived, and hyper-concentrated is an extraordinary experimental hurdle. Doing quantitative physics at this frontier requires an entirely new class of specialized diagnostics, both to measure the intense lasers themselves and to use them to generate advanced X-ray and particle probes that can look deep inside high-energy-density matter.

“These machines are extraordinary, but a laser you cannot measure is a laser you cannot do quantitative physics with,” White said. “DELIGHT is about building a standardized toolkit so researchers can turn these massive flashes of energy into reliable data. For my team, that means using these intense lasers to generate the specialized X-ray sources we need to diagnose and see inside extreme states of matter in real time.”

The award comes as a new generation of facilities takes shape. The National Science Foundation ZEUS laser at the University of Michigan is now operating, and the proposed NSF OPAL facility at the University of Rochester would be among the most intense light sources ever built.

"User facilities with high-power lasers will enable tremendous scientific and technological advances over the next decade,” said NSF Plasma Physics program director Vyacheslav "Slava" Lukin. “Team efforts like DELIGHT maximize the scientific value of these facilities by developing systematic measurement capabilities for lasers and plasma, while providing unique training opportunities for students and early-career researchers."

“Operating the highest-power laser system in the United States means we are probing entirely new frontiers of extreme physics, and this new collaboration will help provide the precision diagnostics and advanced modeling our community needs to turn that immense power into transformative scientific discoveries,” Director of the ZEUS facility at the University of Michigan Louise Willingale said.

DELIGHT comprises six complementary projects, including real-time feedback systems that diagnose and correct distortions in a laser's focus at full power, detectors fast enough to keep pace with lasers that fire many times a second, and simulation tools that predict what a given experiment should see:

• Broadband X-ray Sources for High Energy Density Radiography (lead principal investigator Thomas White, University of Nevada, Reno)
• Pulse Optimization and Focal-Spot Feedback (Wendell Hill, University of Maryland)
• Pre-Pulse Metrology and Plasma Mirrors (Douglass Schumacher, The Ohio State University)
• Virtual Diagnostics and Particle-in-Cell Modeling for Ultra-Intense Laser Experiments (Alexander Thomas, University of Michigan)
• Diagnostics of 10 to 200 GeV Electrons (Michael Downer, University of Texas at Austin)
• Real-Time Electronic Detectors for High-Repetition-Rate Proton Radiography (Eleanor Tubman, University of California, Berkeley)

The six projects are designed to interlock rather than run in parallel. A single series of laser shots can test focal-spot metrology, contrast control, X-ray and proton imaging, and electron diagnostics at once, with every measurement checked against the same simulations. White expects the core diagnostic deliverables to be complete within three years.

"To realize the potential of next-generation infrastructure like the proposed NSF OPAL laser, the community needs a standardized, facility-grade diagnostic toolkit," said Jonathan Zuegel of the Laboratory for Laser Energetics and The Institute of Optics at the University of Rochester, principal investigator for NSF OPAL. "Work like this is what makes the difference between having a laser system and having a scientific laser user facility.”

Nevada is an EPSCoR state, part of a federal program that broadens research participation in states historically underrepresented in scientific funding.

DELIGHT will build a national pipeline for students by funding paid positions in advanced scientific research. Through this collaboration, students will have the opportunity to participate in summer research residencies at flagship partner institutions, including the University of Michigan, the University of Texas at Austin, and the University of Maryland. The project team will also host regular symposia at EPSCoR campuses nationwide to provide the mentorship and networking needed to launch careers in academia and national laboratories.