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NASA Reveals New Method for Producing Nuclear Fusion

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EIRNS—In July, a team of NASA researchers announced that they had made significant headway on achieving fusion through a new technique. NASA’s new approach differs from the inertial confinement approaches to fusion (such as at the laser-powered National Ignition Facility) and the magnetic confinement approaches (such as tokamaks), both of which rely on achieving extremely high temperatures to allow the nucleons to overcome the electrostatic repulsion that prevents their easy fusing.

Instead, NASA studied the possibility of causing deuterium-deuterium fusion by implanting the deuterons in a metal lattice. This brings two benefits: First, the deuterons are 1 billion times more densely packed than they would be in the plasma form they would take in a tokamak. Second, the electrons in the metallic structure help to “shield” the electrostatic repulsion between the deuterons, which are both positively charged and therefore difficult to bring together.

They used an external device to shoot high-energy photons at the lattice, causing some deuterons to split into protons and neutrons. The neutrons so produced could then “heat” (strike) other deuterons, causing them, in turn, to run into and fuse with other deuterons, releasing helium-3 and a neutron, which neutron could, in turn, continue the process.

At this point in this idea’s development, the potential for the process to maintain itself through its own reactions has not been reached, but the scientists involved believe that there is a significant potential to scale up the process, to achieve such applications as space power, space propulsion, and the production of radioisotopes. NASA’s press release, with videos, is headlined “NASA Detects Lattice Confinement Fusion.”

Illustration of the main elements of the lattice confinement fusion process observed. In Part (A), a lattice of erbium is loaded with deuterium atoms (i.e., erbium deuteride), which exist here as deuterons. Upon irradiation with a photon beam, a deuteron dissociates, and the neutron and proton are ejected. The ejected neutron collides with another deuteron, accelerating it as an energetic “d*” as seen in (B) and (D). The “d*” induces either screened fusion (C) or screened Oppenheimer-Phillips (O-P) stripping reactions (E). In (C), the energetic “d*” collides with a static deuteron “d” in the lattice, and they fuse together. This fusion reaction releases either a neutron and helium-3 (shown) or a proton and tritium. These fusion products may also react in subsequent nuclear reactions, releasing more energy. In (E), a proton is stripped from an energetic “d*” and is captured by an erbium (Er) atom, which is then converted to a different element, thulium (Tm). If the neutron instead is captured by Er, a new isotope of Er is formed (not shown).