Researchers have made precise mass measurements of four such nuclei, 68-selenium, 70-selenium, 71-bromine and an excited state of 70-bromine. The results may make it easier to understand X-ray ...

One atomic mass unit, or amu, is equal to 1/12 the mass of a single carbon-12 atom. (To put that in perspective, a single carbon atom is roughly equal to 5.857 × 10^-26 ounces.) ...

This diagram maps out atomic motion in separate phonon modes. At left (“LO” represents a longitudinal optical mode), selenium atoms exhibit a clockwise rotation while tungsten atoms stand still. At ...