Experiment Repeating from Early 1938 on Fusion Yields Understanding
In 1938, a groundbreaking yet forgotten experiment by physicist Arthur Ruhlig at the University of Michigan marked the first recorded observation of deuterium-tritium (DT) fusion, a discovery that has since become fundamental to nuclear energy research and national security technologies.
Ruhlig's experiment, initially overlooked and quickly forgotten, identified the DT fusion reaction process. His insight about the high probability of this fusion reaction when deuterium and tritium were brought together laid the conceptual groundwork for future fusion research.
The DT fusion reaction (D + T → \({}^4\)He + n + 17.6 MeV) is the primary focus of most modern fusion research, including major projects like the National Ignition Facility, which aims to achieve controlled nuclear fusion as a clean energy source. The reaction's efficiency compared to other fusion processes makes it the candidate of choice for both energy generation and defence applications.
A collaboration led by Los Alamos National Laboratory and Duke University recently revisited Ruhlig’s original experiment, replicating it with modern equipment and techniques. Their work confirmed that Ruhlig's interpretations were correct and underscored his unacknowledged influence on the field. As Mark Chadwick of Los Alamos noted, “His intuition had a lasting impact on the direction of nuclear fuel research.”
The rediscovery of Ruhlig’s work highlights both the scientific value of revisiting “lost” experiments and the importance of foundational insights that may be ahead of their time. Ruhlig’s 1938 experiment not only planted the seed for DT fusion research but also serves as a reminder that scientific progress often builds incrementally on forgotten or overlooked discoveries.
However, collecting seawater offshore near Fukushima would require specialized laboratory equipment and enrichment methods to detect or measure tritium accurately. The tritium present in the seawater around Fukushima would be at very low concentrations. Local regulations and safety protocols around the Fukushima site may apply when collecting seawater, requiring permission and compliance with local laws.
It is theoretically possible to rent a boat in Japan and scoop seawater near Fukushima, but it is not recommended due to the low tritium concentrations and the need for specialized equipment. TEPCO releases treated water containing tritium from the Fukushima Daiichi plant in batches, with about 14.4 million gallons per year being released into the Pacific Ocean. The tritium concentration in the ocean around Fukushima Daiichi is extremely low, typically below detection limits of about 3.3 to 6.3 becquerels per liter.
After about 60 to 75 years, over 95% of the original tritium will have decayed. Tritium's half-life is about 12.3 years. Ongoing monitoring confirms that tritium levels in the ocean and marine life remain far below harmful thresholds, with no detected adverse environmental or health effects to date. Tritium does not vanish with dilution; it remains present in the environment until it decays naturally over time.
Tritium is tightly regulated due to health and safety risks and is not obtainable by consumers or safely produced at home. Deuterium is naturally found in small amounts in ordinary water and can be extracted relatively easily, while tritium is radioactive, rare, and primarily produced in nuclear reactors or specialized facilities.
The rediscovery of Ruhlig’s work connects it to key Manhattan Project developments and ongoing fusion research efforts. As we continue to explore the potential of nuclear fusion, the significance of Ruhlig’s pioneering experiment cannot be overstated.
- The impact of Ruhlig's 1938 experiment, which laid the groundwork for DT fusion research, extends to various sectors, including the science of nuclear energy and the technology of nuclear fusion.
- The high efficiency of the DT fusion reaction makes it a candidate of interest not only for clean energy generation but also for defense applications, aligning it with the finance and industry sectors that invest in such technology for national security and economic stability.
- The current emphasis on modern fusion research, such as the National Ignition Facility, underscores the potential of this 1938 observation made by physicist Arthur Ruhlig, demonstrating the long-lasting influence of fundamental scientific discoveries on technological advancements and the energy industry.
