Pentaquarks, locked-in syndrome and more reader feedback

Behold the pentaquark

Quarks, the building blocks of protons and neutrons, travel in packs. Researchers at the Large Hadron Collider near Geneva caught a glimpse of two new five-quark particles, Andrew Grant wrote in “LHC reports pentaquark sightings” (SN: 8/8/15, p. 8).

“In the story, particle physicists at the LHC report that a pentaquark contains a charm quark and its antimatter counterpart,” Terry Breen wrote in an e-mail.