Quarks fuse to release energy
In nuclear fusion, energy is produced by the rearrangement of protons and neutrons. The discovery of an analogue of this process involving particles called quarks has implications for both nuclear and particle physics. See Letter p.89 The LHCb collaboration at CERN's Large Hadron Collider recently reported the discovery of a doubly charmed baryon with a large binding energy between the two charm quarks inside it. Marek Karliner and Jonathan Rosner report that this strong binding energy allows for a rearrangement of the quarks that releases energy in a quark-level analogue of deuterium–tritium nuclear fusion. They point out that the even larger binding energy between two bottom quarks can also enable such an exothermic rearrangement, with a considerably larger energy release.