Scientists at the X-ray free-electron laser SwissFEL have realized a long-pursued experimental goal in physics: to show how ...

Open a jewelry box or pause in front of a stained-glass window, and you are seeing one of nature’s quieter tricks at work. The color, in these cases, is not painted on. It comes from the atoms ...

Different atoms and ions possess characteristic energy levels. Like a fingerprint, they are unique for each species. Among ...