Dr. Debbie Callahan (Focused Energy, Inc. and Lawrence Livermore National Laboratory)

"From Ignition on NIF to Fusion Energy on the Grid using Proton Fast-Ignition"

Abstract: Recently the National Ignition Facility (NIF) laser has enabled major breakthroughs in inertial fusion [1,2,3,4,5]: first a burning plasma, then ignition, then gain > 1. These results have renewed interest in inertial fusion as a source of clean energy. But huge challenges remain in generating electricity from a fusion power plant. A power plant will require gain of ~100, rather than 2. The repetition-rate and efficiency of the laser will need to be increased. More robust, cheaper targets are also essential.Focused Energy is a private company founded in 2021 that pursues inertial fusion energy using diode-pumped lasers to drive a proton fast ignition target design [6]. Proton fast ignition promises the higher gain and robustness needed for a power plant, but raises new physics questions. After summarizing the NIF results, I will discuss the lessons learned on the journey to ignition and the status and challenges of the proton fast ignition approach.

[1] A. B. Zylstra, O. A. Hurricane, D. A. Callahan, A. K. Kritcher, et al, Nature, 601, 542 (2022).

[2] A. Kritcher, C. Young, H. Robey, et al, Nat. Phys. 18, 251 (2022).

[3] H. Abu-Shawareb, et al (Indirect Drive ICF Collaboration), Phys Rev. Letters, 129, 075001 (2022).

[4] A. L. Kritcher, A. B. Zylstra, D. A. Callahan, O. A. Hurricane, et al, Phys Rev E, 106 025201 (2022).

[5] A. B. Zylstra, A. L. Kritcher, O. A. Hurricane, D. A. Callahan, et al, Phys Rev E, 106, 025202 (2022)

[6] M. Roth et al, Phys Rev Letters, 86, 436 (2001).

Bio: Debra (Debbie) Callahan is co-lead for IFE Science at Focused Energy Inc., which she joined after 35 years at Lawrence Livermore National Laboratory as a physicist and associate division leader for HED-ICF target design. She was part of the scientific leadership of the team that recently achieved ignition on the National Ignition Facility (NIF) Laser. Dr Callahan is a Fellow of the American Physical Society and a co-recipient of the Dawson Award for Excellence in Plasma Physics in 2012 and 2022. She was recognized in 2022 by Fusion Power Associates for "her decades of leadership and outstanding contributions to the design of hohlraum targets for implosion experiments on NIF." She was awarded the Ronald Davidson Prize by the American Institute of Physics (2023) and the E. Gail de Planque Medal (2023) by the American Nuclear Society for her contributions to fusion and nuclear science.