Science Highlights

Many particle accelerators rely on superconducting radiofrequency components made of niobium. Nuclear physicists found that dissolving oxygen atoms a few micrometers into niobium greatly improves the performance of components made of the metal. Now, the researchers are perfecting a model using different processes for adding oxygen. The model helps to predict and optimize component performance.

The shape of nanoparticles depends on the choice of solvent and temperature during their growth, but the seed particles that form first are too small to measure accurately. Researchers have developed a new approach to successfully model seed particles with 100 to 200 atoms. They found that the shapes of the tiny particles depend on the solvent composition and temperature in unexpected ways.

Promethium’s short half-life and lack of stable isotopes makes it difficult to study. In addition, promethium is difficult to separate from other lanthanide elements because of these elements’ similarity. In this study, scientists created a pure sample of the isotope promethium-147 and used X-ray absorption spectroscopy to examine the way it chemically bonds. This information will lead to better separation methods and increased promethium production.

To make inorganic materials such as catalysts, industry mixes precursor powders and fires them in an oven. This often produces a mix of compositions and structures. In this study, researchers developed a new way to select precursors to increase yield and quickly validated their results using a robotic lab. The new recipe selection process obtained higher purity for 32 of the 35 target materials.

Through the weak nuclear force, one quark flavor can transmute into another. However, current data and theory indicate that the probabilities of quark flavor transmutation do not add up to 100%, as predicted by the Standard Model of Particle Physics. To understand whether this is due to physics beyond the Standard Model or underestimated uncertainties, nuclear theorists laid out a new framework needed to extract the up-down quark flavor mixing with a precision of a few parts in ten thousand from certain nuclear beta decays.

Scientists have long held that electricity is carried by individual electrons with discrete charges moving in a metal, even in the case of electrons clumped into quasiparticles. However, “strange metals” fail to obey this paradigm. Researchers have observed a radical quantum blurring of electrons in strange metal into a featureless liquid, potentially pointing toward a new theory of electrical transport.

Atomic nuclei with “magic numbers” of protons or neutrons in their nuclear shells are extremely stable. Nuclear physicists are especially interested in nuclei with doubly magic numbers—those that have full shells for both protons and neutrons. One example is the tin isotope Sn-100, which has 50 protons and 50 neutrons. To prepare for future work on Sn-100, researchers studied the properties of isotopes of indium as they approached 50 neutrons. This helps to demonstrate how adding single particles changes the properties of a nucleus.

Bacteria commonly produce toxins that are lethal to themselves, but also produce the required antitoxins. These toxin-antitoxin (TA) systems may be useful in modifying bacteria for biotechnology applications, but the systems have unpredictable behavior. A new study of communities instead of individual species makes TA systems easier to understand and use.