Helium is the second most abundant element in the Universe, after hydrogen. The nucleus of its most common isotope, helium-4, consists of two protons and two neutrons and is called the α-particle.

How big is a helium atom? Or maybe the better question is: How small? After an intricate game of particle jockeying, physicists have now measured the radius of the helium nucleus five times more ...

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 ...

Researchers in Argonne's Physics Division teamed up to conduct the most precise measurement ever made of the charge radius — one aspect of the size — of the Borromean nucleus of helium-6. ARGONNE, ...

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 ...

A research team has achieved a significant breakthrough in determining fundamental properties of atomic nuclei. The team conducted laser spectroscopy experiments on muonic helium-3. Muonic helium-3 is ...

This demanding experiment is only possible with the help of PSI's proton accelerator facility. There Aldo Antognini's team generates so-called muonic helium-3, in which the two electrons of the helium ...