After much delay, CERN’s Large Hadron Collider (LHC) has been accumulating proton-proton data since April, albeit at only half the 14-TeV collision energy for which it was designed. Its predecessor, the 2-TeV Tevatron proton-antiproton collider at Fermilab, was scheduled to shut down for good at the end of 2011. But the Tevatron’s excellent performance over the past two years and the LHC’s delayed ramp-up to its design parameters prompted Fermilab’s program advisory committee in August to recommend that the Tevatron be kept running through 2014.
That extension would cost an estimated $130 million. So HEPAP, the high-energy-physics advisory panel to the funding agencies, asked its particle-physics project prioritization subpanel (P5) to assess the scientific merit of the proposed extension and weigh it against anticipated negative impacts on the rest of the US particle-physics program.
At a special HEPAP meeting on 26 October, P5 chairman Charles Baltay (Yale University) presented the...
