Xenon takes a turn in the LHC

For the first time, the Large Hadron Collider is accelerating xenon nuclei for experiments. Most of the year, the Large Hadron Collider at CERN collides protons. LHC scientists have also accelerated lead nuclei stripped of their electrons. Today, for just about eight hours, they are experimenting with a different kind of nucleus: xenon. Xenon is a heavy noble gas that exists in trace quantities in the air. Xenon nuclei are about 40 percent lighter than lead nuclei, so xenon-xenon collisions have...