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When two helium-4 (⁴He) nuclei smash together, they form a beryllium-8 nucleus. A third ⁴ He striking this nucleus may result in an excited form of carbon-12 (¹² C), with the ⁴ He particles arranging in a neat cluster. Clustering of neutrons and protons during high-energy collisions is known to determine the stability of the collision products. But how clustering affects the dynamics and reaction outcomes of high-energy collisions remains an open question. Now Catalin Frosin of the University of Florence, Italy, and his colleagues report experimental data that detail how reaction products form during this kind of collision [1]. The results support models that suggest increased collision energy can drive clustering activity and result in emission of lighter, more energetic particles.

The experiments entail bombarding ¹² C targets with pulsed beams of sulfur-32 and neon-20. Frosin and his colleagues characterized the resulting fragments using FAZIA, a detector designed to probe charged particles around the Fermi energy. Meanwhile, the team ran simulations, with and without cluster correlations, to predict the nucleon interactions and the decays of unstable products. Models with clustering produced particles that are more energetic—in agreement with the experimental data. The researchers attributed this effect to energy and momentum conservation in the nucleon–nucleon and nucleon–cluster collisions during the early, dynamic phase of the interaction.

The findings demonstrate FAZIA’s capability to extract precise information about the properties of nuclear fragments. The researchers say that similar experiments performed elsewhere looked only at carbon+carbon reactions. Extending them to heavier reactants provides a wider arena for interpreting fragmentation mechanisms.

The University of Illinois Urbana-Champaign’s nuclear physics group is participating in the nEDM experiment at Oak Ridge National Laboratory, aiming to measure the neutron’s electric dipole moment to constrain theories in particle physics. The researchers aim to construct sensors for the nEDM experiment and explore their potential applications in quantum information science. The unique quantum properties of nitrogen-vacancy diamond make it a promising candidate for quantum sensing and quantum memory.

The nuclear physics group at the University of Illinois Urbana-Champaign is looking for evidence of new physics in neutrons, electrically neutral particles that hold atomic nuclei together with an interaction called the strong force. Faculty and researchers are participating in the nEDM experiment at Oak Ridge National Laboratory which will measure the neutron’s electric dipole moment, a property that allows neutrons to interact with electric fields despite their neutrality. A precise measurement will constrain theories extending the current standard model of particle physics. To achieve this, the researchers must accurately measure subtle changes in very strong electric fields.

Professor of Physics Douglas Beck has been awarded a grant from the Department of Energy to develop sensors based on nitrogen-vacancy diamond, a material whose quantum properties at low temperatures make it unusually sensitive to electric fields. His research group has shown that the material can measure strong electric fields, and the award will allow the researchers to construct sensors ready to use in the nEDM experiment. In addition, the material’s quantum properties make it a promising candidate for quantum information science. The researchers will also explore these potential applications.

In a development that could make quantum computers less prone to errors, a team of physicists from Quantinuum, California Institute of Technology and Harvard University has created a signature of non-Abelian anyons (nonabelions) in a special type of quantum computer. The team has published their results on the arXiv preprint server.

As scientists work to design and build a truly useful quantum computer, one of the difficulties is trying to account for errors that creep in. In this new effort, the researchers have looked to anyons for help.

Anyons are quasiparticles that exist in two dimensions. They are not true particles, but instead exist as vibrations that act like particles—certain groups of them are called nonabelions. Prior research has found that nonabelions have a unique and useful property—they remember some of their own history. This property makes them potentially useful for creating less error-prone quantum computers. But creating, manipulating and doing useful things with them in a quantum computer is challenging. In this new work, the team have come close by creating a physical simulation of nonabelions in action.

Ocean microplastics have become a major source of concern, especially since they are so hard to track down, but researchers found an ingenious solution using satellites.

Ocean plastics have become a major source of concern for evironmental conservationists and public health professionals in recent years, and there hasn’t been a good way to track how these plastics are moving or their concentrations. But now, researchers from the University of Michigan have developed an ingenious way to track the ebb and flow of these microplastics around the world thanks to NASA satellites.

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An algorithm that allows more precise forecasts of the positions and velocities of a beam’s distribution of particles as it passes through an accelerator has been developed by researchers with the Department of Energy (DOE) and the University of Chicago.

Traveling at nearly light speed, the linear accelerator at the DOE’s SLAC National Accelerator Laboratory fires bursts of close to one billion electrons through long metallic pipes to generate its particle beam. Located in Menlo Park, California, the facility, originally called the Stanford Linear Accelerator Center, has used its 3.2-kilometer accelerator since its construction in 1962 to propel electrons to energies as great as 50 gigaelectronvolts (GeV).

The powerful particle beam generated by SLAC’s linear accelerator is used in the study of everything from innovative materials to the behavior of molecules on the atomic scale, despite how the beam itself remains somewhat mysterious since researchers have a hard time gauging its appearance as it passes through an accelerator.

Exceptionally well-preserved fossils from the Cambrian period have helped fill a gap in our understanding of the origin and evolution of major animal groups alive today.

A new analysis of fossils belonging to an extinct invertebrate called Rotadiscus grandis have helped place this species in the animal tree of life, revealing how some characteristics of living species may have evolved independently rather than originating in a single common ancestor.

Half a billion years ago, an unusual-looking animal crawled over the sea floor, using tentacles to pick up food particles along the way.

A surprise observation of negative mass in exciton–polaritons has added yet another dimension of weirdness to these strange light-matter hybrid particles.

Dr. Matthias Wurdack, Dr. Tinghe Yun and Dr. Eliezer Estrecho from the Department of Quantum Sciences and Technology (QST) were experimenting with exciton polaritons when they realized that under certain conditions the dispersion became inverted—equating to a negative mass.

To add to the surprise, the unexpected cause has turned out to be losses.

The exotic particles are called non-Abelian anyons, or nonabelions for short, and their Borromean rings exist only as information inside the quantum computer. But their linking properties could help to make quantum computers less error-prone, or more ‘fault-tolerant’ — a key step to making them outperform even the best conventional computers. The results, revealed in a preprint on 9 May¹, were obtained on a machine at Quantinuum, a quantum-computing company in Broomfield, Colorado, that formed as the result of a merger between the quantum computing unit of Honeywell and a start-up firm based in Cambridge, UK.

“This is the credible path to fault-tolerant quantum computing,” says Tony Uttley, Quantinuum’s president and chief operating officer.

Other researchers are less optimistic about the virtual nonabelions’ potential to revolutionize quantum computing, but creating them is seen as an achievement in itself. “There is enormous mathematical beauty in this type of physical system, and it’s incredible to see them realized for the first time, after a long time,” says Steven Simon, a theoretical physicist at the University of Oxford, UK.

Physicists have discovered “stacked pancakes of liquid magnetism” that may account for the strange electronic behavior of some layered helical magnets.

The materials in the study are magnetic at cold temperatures and become nonmagnetic as they thaw. Experimental physicist Makariy Tanatar of Ames National Laboratory at Iowa State University noticed perplexing electronic behavior in layered helimagnetic crystals and brought the mystery to the attention of Rice theoretical physicist Andriy Nevidomskyy, who worked with Tanatar and former Rice graduate student Matthew Butcher to create a computational model that simulated the quantum states of atoms and electrons in the layered materials.

Magnetic materials undergo a “thawing” transition as they warm up and become nonmagnetic. The researchers ran thousands of Monte Carlo computer simulations of this transition in helimagnets and observed how the magnetic dipoles of atoms inside the material arranged themselves during the thaw. Their results were published in a recent study in Physical Review Letters.