SAND2007-2984P PULSED POWER AT SANDIA NATIONAL LABORATORIES LABORATORIES NATIONAL SANDIA PULSED POWER AT WHAT IS PULSED POWER . the first forty years In the early days, this technology was often called ‘pulse power’ instead of pulsed power. In a pulsed power machine, low-power electrical energy from a wall plug is stored in a bank of capacitors and leaves them as a compressed pulse of power. The duration of the pulse is increasingly shortened until it is only billionths of a second long. With each shortening of the pulse, the power increases. The final result is a very short pulse with enormous power, whose energy can be released in several ways. The original intent of this technology was to use the pulse to simulate the bursts of radiation from exploding nuclear weapons. Anne Van Arsdall Anne Van Pulsed Power Timeline (over) Anne Van Arsdall SAND2007-????? ACKNOWLEDGMENTS Jeff Quintenz initiated this history project while serving as director of the Pulsed Power Sciences Center. Keith Matzen, who took over the Center in 2005, continued funding and support for the project. The author is grateful to the following people for their assistance with this history: Staff in the Sandia History Project and Records Management Department, in particular Myra O’Canna, Rebecca Ullrich, and Laura Martinez. Also Ramona Abeyta, Shirley Aleman, Anna Nusbaum, Michael Ann Sullivan, and Peggy Warner. For her careful review of technical content and helpful suggestions: Mary Ann Sweeney. For their insightful reviews and comments: Everet Beckner, Don Cook, Mike Cuneo, Tom Martin, Al Narath, Ken Prestwich, Jeff Quintenz, Marshall Sluyter, Ian Smith, Pace VanDevender, and Gerry Yonas. For their assistance with and comments on content: Malcolm Buttram, Jim Lee, Ray Leeper, Keith Matzen, Tom Mehlhorn, Tom Sanford, and Charles Shirley. Scientists and engineers for information provided: Ray Clark, Ellis Dawson, Steve Downie, Mike Desjarlais, Mark Kiefer, Dan Jobe, David L. Johnson, Barbara Lewis, John Maenchen, Dillon McDaniel, Cliff Mendel, Craig Olson, Charlie Robinson, Johann Seamen, Dave Seidel, Steve Shope, and A.W. Snyder. iv CONTENTS CHAPTER ONE from 1960-1970....................................................... 1 Technical Sidebars Atomic Energy Commission to National Nuclear Security Administration.................... 2 Weapons Effects Simulation and Radiation Effects..................................... 4 The Cable Pulser.............................................................. 6 Pulsed Power Technology ....................................................... 9 Spastic .................................................................... 10 Hermes I and II .......................................................... .14-15 REBA ..................................................................... 17 Hydra and SLIM .......................................................... .20-21 Lasers ..................................................................... 22 CHAPTER TWO from 1970-1980 ..................................................... .27 Technical Sidebars Fusion..................................................................... 28 Beckner, Yonas, Narath........................................................ 32 Wire-On-Axis Research........................................................ 34 Early Codes.............................................................. .40-41 Proto I and Proto II ....................................................... .42-43 Countdown to EBFA/PBFA I ..................................................... 48 Particle Beam Weapons Make Headlines........................................... 50 Magnetically Self-Insulated Transmission Lines...................................... 53 v EBFA-PBFA: Electron Beams vs. Ion Beams ..................................... .54-55 PBFA II Funding ............................................................. 56 CHAPTER THREE from 1980-1990 .................................................. 6 3 Technical Sidebars Recollections of the First Shot on PBFA I........................................... 65 PBFA I ................................................................. .66-67 Major Strategic Defense Initiative Work at Sandia ................................. .74-76 A 1984 Perspective of the Strategic Defense Initiative ................................. 77 PBFA II: Technical Timeline ................................................. .80-83 PBFA II ................................................................. .84-85 Later Computer Codes for Fusion ............................................. .86-88 On the Scene at PBFA II........................................................ 92 Saturn.................................................................. .94-95 Hermes III .............................................................. .96-97 New Record on PBFA II........................................................ 99 Prestwich and Martin Awards .................................................. 100 CHAPTER FOUR from 1990 to ZR ................................................... .105 Technical Sidebars The Proposed Microfusion Facility .......................................... .108-110 Fusion Concepts-direct and indirect drive......................................... 111 International Collaborations ............................................... .112-113 The Fusion Policy Advisory Committee ........................................... 115 PBFA II Target Experiments, 1991............................................... 117 The National Ignition Facility............................................... .120-121 Science-Based Stockpile Stewardship ........................................ .122-123 Sculpture Honors Pulsed Power Researchers ...................................... 126 Z Pinch ................................................................... 127 Sandia’s 1995 Breakthrough with Z Pinches ................................... .128-129 Final Results of Sandia’s Ion Beam Research................................... .132-133 Highlights from Z ....................................................... .134-135 VanDevender, Yonas Pulsed Power Awards ........................................ 136 Z-Pinch Inertial Fusion Energy ............................................. .140-141 ZR................................................................... .142-143 Z-Beamlet ............................................................. .144-146 vi INTRODUCTION Pulsed power accelerators store electrical energy, compress it in time and space, and deliver it to a target as strong, short, fast-rising pulses of power. How the energy is delivered determines the type of radiation, or the beam, that will be produced. Sandia needed such capability beginning in the 1960s for one of its traditional responsibilities, weapons effects simulations. The military was building new kinds of electronics into warheads, and the United States needed to test their vulnerability to radiation from an enemy’s nuclear weapons. The accelerators could simulate the effects of those weapons and harden US warheads against them. Chapter one of this history outlines the early years of pulsed power at Sandia, the 1960s and early 1970s, when collaborations with the Atomic Weapons Research Establishment in the United Kingdom resulted in Sandia’s building relatively small machines capable of simulating gamma rays and then x rays. At the same time, the Department of Defense was building competing accelerators for the same purpose, some of them attempting to create controlled fusion events in the laboratory in classified experiments. (Uncontrolled fusion reactions are used as the secondaries in nuclear weapons.) In parallel with accelerator development, the newly invented laser was being established as an important technology for many of the same applications as accelerators at Lawrence Livermore, Los Alamos, and Sandia laboratories, and at the Naval Research Laboratory. vii During the 1960s, Sandia established a basic research program to support its traditional engineering design work. Al Narath and Everet Beckner, two new staff members who rose quickly into higher management, spearheaded this effort, and out of this program came the push to get Sandia into the inertial confinement nuclear fusion arena. Nuclear fusion was at the time dominated by Livermore and Los Alamos, using lasers as drivers. Realizing that pulsed power accelerators might be suited to fusion research, Narath and Beckner saw a fusion program as one way to attract new talent to Sandia. In addition, fusion research would help bolster Sandia’s role in national defense and other areas and also had the potential for In inertial confinement fusion, x-ray development as a source of energy, which greatly added to its appeal.* illumination leads to . Chapter two covers roughly the decade of the 1970s. In the early years of that decade, Narath and Beckner hired Gerry Yonas into Sandia because of his expertise at Physics International with large accelerators and fusion work. Very soon after coming to Sandia, Yonas began to champion Sandia’s accelerators as potential drivers for inertial confinement fusion to the Department of Energy and Congress. Because lasers were seen as the frontrunner technology for fusion, the proposal to consider accelerators for the same purpose was viewed with some skepticism. Indeed, Livermore and Los Alamos did not welcome what they considered a dark- horse contender in the fusion arena. Pulsed power accelerators and their particle beams did