NSF-UEFISCDI: Generation of Energetic Electrons and Gamma-Rays in a High-Intensity Laser-Plasma Interactions

About This Grant

Sources of gamma rays —- an extremely energetic form of light —- are needed for national security, nuclear waste analysis, and medical isotope production, as well as for fundamental studies of matter and antimatter creation from light alone. This joint project between the University of California San Diego, General Atomics, and Extreme Light Infrastructure - Nuclear Physics (ELI-NP) in Romania will demonstrate a key step towards developing such sources. Powerful lasers uniquely available at ELI-NP will be used to generate strong magnetic fields and ultra-energetic electrons inside a plasma, leading to efficient gamma-ray emission. Hands-on training will be provided to U.S. students and scientists through experiments at the cutting-edge ELI-NP laser facility in Romania, helping to build a skilled workforce in high-intensity laser science. The project will also strengthen scientific collaboration between the U.S. and Romania, offering access to capabilities not currently available in the U.S. while providing complementary expertise to Romanian partners. The project will examine how collective plasma phenomena enhance energy transfer from an intense laser pulse to plasma electrons. Structured targets developed at General Atomics will be employed to independently control two key effects: the generation of a strong azimuthal magnetic field and the laser phase velocity. These effects are expected to enable frequency matching between the oscillating, forward-moving electron and the laser field, while mitigating frequency detuning that would otherwise limit energy gain. The resulting increase in electron energy is anticipated to produce enhanced gamma-ray emission, primarily driven by the plasma magnetic field. The underlying physics will be explored through kinetic simulations and validated experimentally at ELI-NP, where a sequence of two laser pulses will be used to create and probe the structured plasma. The gamma-ray signal will serve as a direct observable of the enhanced energy transfer. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.