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.
August 4, 2023, 3:00PMNuclear News
April 13, 2023, 3:01PMNuclear News
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.
December 8, 2022, 3:00PMNuclear News
Nuclear Newswire is back with the final #ThrowbackThursday post honoring the 80th anniversary of Chicago Pile-1 with offerings from past issues of Nuclear News. On November 17, we took a look at the lead-up to the first controlled nuclear chain reaction and on December 1, the events of December 2, 1942, the day a self-sustaining nuclear fission reaction was created and controlled inside a pile of graphite and uranium assembled on a squash court at the University of Chicago’s Stagg Field.
December 1, 2022, 12:01PMNuclear News
On the eve of the 80th anniversary of the first controlled nuclear chain reaction, Nuclear Newswire is back with the second of three prepared #ThrowbackThursday posts of CP-1 coverage from past issues of Nuclear News.
On November 17, we surveyed the events of 1942 leading up to the construction of Chicago Pile-1, an assemblage of graphite bricks and uranium “pseudospheres” used to achieve and control a self-sustaining fission reaction on December 2, 1942, inside a squash court at the University of Chicago’s Stagg Field.
Today we’ll pick up where we left off, as construction of CP-1 began on November 16, 1942.
November 17, 2022, 3:08PMNuclear News
As we approach the 80th anniversary of controlled nuclear fission, Nuclear Newswire is prepared to deliver not one but three #ThrowbackThursday posts of CP-1 highlights unearthed from past issues of Nuclear News.
ANS was founded in 1954, nearly 12 years after the first controlled nuclear chain reaction was achieved on December 2, 1942, inside a pile of graphite and uranium assembled on a squash court at the University of Chicago’s Stagg Field. By 1962, ANS was prepared to “salute the 20th anniversary of the first chain reaction” at their Winter Meeting, displaying a model of Chicago Pile-1 and presenting a specially cast medal to Walter Zinn, a representative of Enrico Fermi’s scientific team. Over the years, ANS has continued to mark significant anniversaries of CP-1 at national meetings and in NN.
December 17, 2020, 12:00PMANS Nuclear Cafe
Jack Steinberger, a Nobel Prize–winning scientist with a distinguished career in experimental physics, died December 12. He was 99.
Steinberger was most famous for his co-discovery of a new type of ghostlike particle called the muon neutrino—a breakthrough that earned him, Leon Lederman, and Melvin Schwartz the Nobel Prize in Physics in 1988. Steinberger studied the basic particles that make up the universe, and the elemental forces that govern their interactions, over a long scientific career that was jump-started by Enrico Fermi at the University of Chicago.
March 7, 2019, 4:43PMANS Nuclear Cafe
During March's Women's History Month, I honor Leona Woods by telling #herstory.