Pionic helium In this experiment, a pion – shown here with one orange and one blue particle representing its quark and anti-quark – replaces one of the two electrons in the helium atom. This new metastable atom is then excited with laser light (shown here in red) to probe its properties. (Courtesy: Max Planck Institute of Quantum Optics/Thorsten Naeser) The ability to make artificial atoms containing exotic particles in place of electrons is giving phy You’ve reached the limit of what you can view on Physics World without registering If you already have an account on Physics World, then please sign in to continue reading If you do not yet have an account, please register so you can Access more than 20 years of online content Choose which e-mail newsletters you would like to receive Want to read more? Registration is free, quick and easy Note: The verification e-mail to complete your account registration should arrive immediately. However, in some cases it takes longer. Don't forget to check your spam folder. If you haven't received the e-mail in 24 hours, please contact customerservices@ioppublishing.org. E-mail Address
Particles and interactions Research update Improved antiproton trap could shed more light on antimatter-matter asymmetry