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Physicists use methods called finite-volume simulations with periodic boundary conditions to model the nuclei protons and neutrons can form. This new work solves a long-standing and fundamental problem for electrically charged systems in these “periodic boxes.” It derives the mathematical equation that describes how the properties of these electrically charged systems depend on the size of the simulation volume.

Background radioactivity from cables in equipment for ultra-precise physics experiments can impair those experiments. To address this challenge, scientists examined the radioactive contaminants introduced when cables are produced and identified alternative methods of cleaning and preparing the cables to reduce the amount of uranium-238 and thorium-232. The resulting cables will aid future physics experiments.

Microbes called anaerobic methanotrophic archaea form communities with sulfate reducing bacteria. These communities can consume methane in anaerobic environments. This research found that biological processes in these microbial communities can create silica deposits that appear to entomb the communities. This process helps to preserve these communities in the geological record.

According to the traditional model of nuclear shells, oxygen-28 is expected to be a doubly magic nucleus with 20 neutrons and 8 protons. However, an experiment performed at the Rare Isotope Beam Facility in Japan measured the direct decay of oxygen-28 into four neutrons and oxygen-24 and found that it is not a bound nucleus. This finding challenges theories of nuclear shell structure.

Entanglement entropy quantifies the amount of entanglement between two subsystems. In many systems, the entanglement entropies increase as the area that separates them from their environment increases. In atomic nuclei, however, entanglement entropies increase as the volume of the system of interest increases, not the volume of the environment. New research quantifies entanglement entropies for neutron matter and atomic nuclei.

Polyolefins are resistant to breaking down, making them hard to recycle. Scientists have now discovered a yeast, Yarrowia lipolytica, that uses hydrocarbons derived from polyolefin plastic wastes to produce substances that can be used to make biodegradable polyesters and polyurethanes. This would advance progress toward biological upcycling of plastic wastes in a circular bioeconomy.

Like protons and neutrons, Lambda particles consist of three quarks bound together by gluons. But unlike protons and neutrons, which contain a mixture of up and down quarks, Lambdas also contain a strange quark. Nuclear physicists recently made the first observations of how Lambda particles are produced, finding that Lambdas were sometimes produced after an electron exchanged a packet of energy referred to as a virtual photon with a target nucleus. This differs from theoretical predictions.

The tantalum isotope, Ta-180m, is found naturally in a long-lived excited state. However, the radioactive decay of this excited state in Ta-180m has never been observed. Researchers are now conducting experiments that aim to measure this decay, which is expected to have a lifetime approximately 1 million times longer than the age of the universe.

When scientists collide heavy nuclei, the constituent quarks and gluons melt into a quark-gluon plasma. The shape and the size of the quark-gluon plasma is affected by the thickness of the nuclei’s neutron skin, allowing inferences about the skin from experiments. In this study, researchers compared the parameters of a theoretical model to experimental results to find the value for the neutron skin of lead-208 that best describes the data.