Precision spectroscopy of helium and related atomic systems continues to serve as a cornerstone of experimental and theoretical quantum physics, offering stringent tests of quantum electrodynamics and ...

Helium-3 is the lighter cousin of ordinary helium, helium-4. Its atomic nucleus has two protons and two neutrons (hence the 4 after the abbreviation for the element); in helium-3, one of the neutrons ...

For the first time, researchers from the PRISMA + Cluster of Excellence have determined the charge radius of helium-3 and thus also the exact difference to the radius of helium-4. This precision ...

In experiments at the Paul Scherrer Institute PSI, an international research collaboration has measured the radius of the atomic nucleus of helium five times more precisely than ever before. With the ...

The Nature Index 2024 Research Leaders — previously known as Annual Tables — reveal the leading institutions and countries/territories in the natural and health sciences, according to their output in ...