Scientists have made a groundbreaking discovery in nuclear physics, measuring the heaviest nucleus ever recorded to decay via proton emission. This achievement marks the first time such a feat has been accomplished in over 30 years, with the previous record set in 1996.

The research team from the University of Jyväskylä, Finland, successfully produced and measured the lightest known isotope of astatine, 188At, consisting of 85 protons and 103 neutrons. This exotic nucleus was created through a complex process involving a fusion-evaporation reaction and identified using a sophisticated detector setup.

“The properties of this nucleus reveal a trend change in the binding energy of the valence proton,” explains Doctoral Researcher Henna Kokkonen, who led the study. “This could be explained by an interaction unprecedented in heavy nuclei.”

The research team’s findings have significant implications for our understanding of atomic nuclei and their behavior. By expanding a theoretical model to interpret the measured data, scientists can now better comprehend the intricate mechanisms governing these complex systems.

Kokkonen notes that studying such exotic nuclei is extremely challenging due to their short lifetimes and low production cross sections. However, precise techniques like those employed in this study have made it possible to unlock new insights into the fundamental nature of matter.

The research article was published in Nature Communications as part of an international collaboration involving experts in theoretical nuclear physics. This breakthrough discovery not only pushes the boundaries of human knowledge but also has far-reaching implications for our understanding of the universe and its mysteries.

The development of artificial intelligence (AI) in fusion research has taken a significant leap forward. A public-private partnership between Commonwealth Fusion Systems (CFS), the U.S. Department of Energy’s Princeton Plasma Physics Laboratory (PPPL), and Oak Ridge National Laboratory has led to the creation of HEAT-ML, an AI approach that rapidly finds and simulates “magnetic shadows” in fusion vessels: safe havens protected from intense heat plasma.

HEAT-ML uses a deep neural network to learn how to calculate shadow masks, which are 3D maps of specific areas on internal components shielded from direct heat. This AI surrogate was trained using a database of approximately 1,000 SPARC simulations and can now simulate the same calculations in mere milliseconds, as opposed to the previous 30 minutes.

The goal is to create software that significantly speeds up fusion system design and enables good decision-making during operations by adjusting plasma settings to prevent potential problems. HEAT-ML was specifically designed for a small part of the SPARC tokamak under construction by CFS but has the potential to be expanded to generalize the calculation of shadow masks for exhaust systems of any shape and size, as well as other plasma-facing components.

Researchers believe that this AI breakthrough could pave the way for faster fusion system design, enabling good decision-making during operations, and potentially leading to limitless amounts of electricity on Earth.

The Large Hadron Collider (LHC), a 17-mile particle accelerator buried under the French-Swiss border, has achieved the centuries-old dream of alchemists: transforming lead into gold. However, this accomplishment was not without its limitations – it happened within a fraction of a second. The scientists reported their results in Physical Reviews.

The achievement was made possible by the sophisticated and sensitive detector called ALICE, which is roughly the size of a McMansion. It was scientists from the University of Kansas, working on the ALICE experiment, who developed the technique that tracked “ultra-peripheral” collisions between protons and ions that resulted in gold creation at the LHC.

According to Daniel Tapia Takaki, professor of physics and leader of KU’s group at ALICE, these ultra-peripheral collisions involve near misses between particles. The ions racing around the LHC tunnel are heavy nuclei with many protons, each generating powerful electric fields. When accelerated, these charged ions emit photons – they shine light.

“When you accelerate an electric charge to near light speeds, it starts shining,” Tapia Takaki said. “One ion can shine light that essentially takes a picture of the other. When that light is energetic enough, it can probe deep inside the other nucleus, like a high-energy flashbulb.”

During these ultra-peripheral collisions, surprising interactions can occur, including the creation of gold through photon-photon collisions. These events are incredibly clean, with almost nothing else produced. They contrast with typical collisions where sprays of particles flying everywhere.

However, the ALICE detector and the LHC were designed to collect data on head-on collisions that result in messy sprays of particles. These clean interactions were hard to detect with earlier setups.

Tapia Takaki’s KU co-authors on the paper are graduate student Anna Binoy; graduate student Amrit Gautam; postdoctoral researcher Tommaso Isidori; postdoctoral research assistant Anisa Khatun; and research scientist Nicola Minafra. The KU team at the LHC ALICE experiment plans to continue studying the ultra-peripheral collisions.

Tapia Takaki said that while the creation of gold fascinated the public, the potential of understanding the interactions goes deeper. This light is so energetic, it can knock protons out of the nucleus, sometimes one, sometimes two, three or even four protons. We can see these ejected protons directly with our detectors.

Each proton removed changes the elements: One gives thallium, two gives mercury, three gives gold. These new nuclei are very short-lived, they decay quickly, but not always immediately. Sometimes they travel along the beamline and hit parts of the collider – triggering safety systems.

That’s why this research matters beyond the headlines. With proposals for future colliders even larger than the LHC – some up to 100 kilometers in Europe and China – you need to understand these nuclear byproducts. This ‘alchemy’ may be crucial for designing the next generation of machines.

This work was supported by the U.S. Department of Energy Office of Science, Office of Nuclear Physics.