In Big Bang nucleosynthesis (BBN), the deuterium-tritium (DT) fusion reaction ³H(d,n)⁴He, enhanced by the 3/2⁺ “Bretscher resonance,” is responsible for 99 percent of primordial helium-4. While this fact has been known for decades, it has not been widely appreciated. The importance of the resonant nature of the DT fusion reaction has been amplified by recent activities related to the production and use of terrestrial fusion, including the recent net-gain shot at the National Ignition Facility (NIF). Here, we aim to highlight the anthropic importance of the ⁴He-producing DT reaction that plays such a prominent role in models of nucleosynthetic processes occurring in the early universe. This primordial helium serves as a source for the subsequent creation of more than 25 percent of the carbon (¹²C) and other heavier elements that compose a substantial fraction of the human body. Further studies are required to determine a better characterization of the amount of ¹²C than this lower limit of 25 percent. Some scenarios of core stellar nucleosynthetic yield of ¹²C suggest that even higher percentages of carbon from primordial helium are possible.

Focused Energy and Xcimer Energy are two of the eight fusion developers the Department of Energy selected in late May for funding under the public-private Milestone-Based Fusion Development Program, and the only developers using an inertial confinement concept. The Milestone program, announced in September 2022, was open to any fusion developer willing to undergo a competitive merit-review process, regardless of fusion confinement concept. But the prospects for inertial fusion concepts might have gotten a boost from Lawrence Livermore National Laboratory’s December 2022 achievement of scientific breakeven at the National Ignition Facility (NIF), which was announced shortly before the application window for the Milestone program closed.

Lawrence Livermore National Laboratory hosted current and former staff, government officials, and media on May 8 to celebrate the lab’s achievement of fusion ignition at the National Ignition Facility (NIF) on December 5, 2022. Energy secretary Jennifer Granholm and undersecretary for nuclear security and National Nuclear Security Administration administrator Jill Hruby were in attendance, and Granholm took the opportunity to announce funding of up to $45 million to support inertial fusion energy (IFE) research and development. The Department of Energy’s Office of Science (DOE-SC) wants to establish multiple IFE Science and Technology Innovation Hubs (IFE S&T hubs), with total funding for 2023 of up to $9 million for projects lasting up to four years in duration.

Physicist Andrea “Annie” Kritcher’s dedication to fusion target design has earned her a spot on the TIME100 Most Influential People list for 2023. Today, Kritcher and 99 other individuals on that list—among them Elon Musk, King Charles, Judy Blume, Patrick Mahomes, Beyoncé, Lionel Messi, Janet Yellen, and MrBeast—are being honored at the TIME100 Summit and Gala at the Lincoln Center in New York City.

Fusion energy research has seen exciting recent breakthroughs. The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory has achieved ignition,^1,2 and in the United Kingdom, the Culham Centre for Fusion Energy’s Joint European Torus (JET) has produced a record 59 megajoules of fusion energy.³ Against this backdrop of advances, we provide an account of the earliest fusion discoveries from the 1930s to the 1950s.* Some of this technical history has not been previously appreciated—most notably the first 1938 reporting of deuterium-tritium (DT) 14-MeV neutrons at the University of Michigan by Arthur Ruhlig.⁴ This experiment had a critical role in inspiring early thermonuclear fusion research directions. This article presents some unique insights from the extensive holdings within Los Alamos National Laboratory’s archives—including sources typically unavailable to a broad audience.

“Star Power” is the name 60 Minutes producers gave their interpretation of the recent experiment at the National Ignition Facility (NIF) that achieved fusion ignition and net gain. Views from inside Lawrence Livermore National Laboratory captured by TV cameras and aired Sunday, January 15—of some of NIF’s 192 lasers, banks of capacitors, target assembly labs, and even the remains of the target assembly blasted in the December 5 breakthrough—are well worth the watch for those of us who are unlikely to visit the site in person.

It’s official: Early in the morning on December 5 at Lawrence Livermore National Laboratory’s National Ignition Facility (NIF), the laser-triggered implosion of a meticulously engineered capsule of deuterium and tritium about the size of a peppercorn yielded, for the first time on Earth, more energy from a fusion reaction than was delivered to the capsule. The input of 2.05 megajoules (MJ) to the target heated the diamond-shelled, spherical capsule to over 3 million degrees Celsius and yielded 3.15 MJ of fusion energy output. The achievement was announced earlier today by officials and scientists representing the Department of Energy and its National Nuclear Security Administration, the White House, and LLNL during a livestreamed event.

Just over one year ago, on August 8, 2021, researchers achieved a yield of more than 1.3 megajoules (MJ) at Lawrence Livermore National Laboratory’s National Ignition Facility (NIF) for the first time, achieving scientific ignition and getting closer to fusion gain.

The scientific results of the historic experiment were published exactly one year later in three peer-reviewed papers: one in Physical Review Letters and two (an experimental paper and a design paper) in Physical Review E. In recognition of the many individuals who worked over decades to enable the ignition milestone, more than 1,000 authors are included on the Physical Review Letters paper.

One of the last remaining milestones in fusion research before attaining ignition and self-sustaining energy production is creating a burning plasma, where the fusion reactions themselves are the primary source of heating in the plasma. A paper published in the journal Nature on January 26 describes recent experiments at Lawrence Livermore National Laboratory’s National Ignition Facility (NIF) that have achieved a burning plasma state.

Hurricane

In 2012, Omar Hurricane, a distinguished member of the technical staff at Lawrence Livermore National Laboratory, was asked by the laboratory director to lead a team to delve into studying the physics and engineering obstacles preventing fusion ignition at the National Ignition Facility (NIF). The team’s efforts led to a new exploratory “basecamp” strategy and the creation of several pivotal experiments that revealed some of the underlying problems with the ignition point design, while also delivering improved fusion performance and the first evidence of significant alpha particle self-heating.

Hurricane was appointed chief scientist of the Inertial Confinement Fusion Program in 2014, a position he has held ever since. He was named a Fellow of the American Physical Society’s Division of Plasma Physics in 2016 and was recently awarded the Edward Teller Medal from the American Nuclear Society for his work on inertial confinement fusion physics.

This is the fourth of five articles to be posted today to look back at the top news stories of 2021 for the nuclear community. The full article, "Looking back at 2021,"was published in the January 2022 issue of Nuclear News.

Quite a year was 2021. In the following stories, we have compiled what we feel are the past year’s top news stories from the July-September time frame—please enjoy this recap from a busy year in the nuclear community.

• Click here to see the first article in the series
• Click here to see the second article in the series
• Click here to see the third article in the series

Lawrence Livermore National Laboratory is celebrating the yield from an experiment at the National Ignition Facility (NIF) of more than 1.3 megajoules of energy—eight times more than the yield from experiments conducted this spring and 25 times more than NIF’s 2018 record yield.