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 ...

On Aug. 18, 1868, a French astronomer named Pierre Jules César Janssen discovered helium while observing a total solar eclipse in India. During the eclipse, Janssen was using a spectroscope to look at ...

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 ...

[Project 326] wanted to know exactly what gas was in some glass tubes. The answer, of course, is to use a spectrometer, but that’s an expensive piece of gear, right? Not really. Sure, these cheap ...