Mark Thomson, a professor of experimental particle physics at the University of Cambridge, takes over as CERN’s director general this week, and one of his first major decisions during his five-year tenure will be shutting down the Large Hadron Collider for an extended upgrade. The shutdown starts in June to make way for the high-luminosity LHC — a major overhaul involving powerful new superconducting magnets that will squeeze the collider’s proton beams and increase their…
