Helium is the simplest element in the periodic table with more than one particle in its nucleus, yet state of the art theory and experiments on it don't add up. When you purchase through links on our ...

There Aldo Antognini's team generates so-called muonic helium-3, in which the two electrons of the helium atom are replaced by an elementary particle called a muon. This allows the nuclear radius to ...

Theoretical calculations predict a complex excited state (0+) for helium-4 (4He) at the 20.21 MeV energy level. This state involves a coupling of three cluster configurations: hydrogen-3 and a proton, ...