LHC restart pushed back again

Physics Today : The Large Hadron Collider is now on schedule to restart in the winter instead of the fall.The LHC, which has been offline since September last year, has seen its schedule slip back at least three times in recent months as CERN grapples with a number of technical difficulties, including the risk that the collider may not reach 14 TeV . In a series of tests carried out over the last few weeks, CERN staff discovered vacuum leaks in two sectors of the LHC that had been cooled down to 80 K.To repair the sectors have to be brought to room temperature—which has to be done gradually over a period of weeks—that will delay beam injection to mid-November says the CERN Bulletin .On a brighter note the shutdown has allowed the various experimental groups to refine and improve their equipment . The CMS group finished a series of experiments with cosmic rays to align the detector, and refurbished the detectors cooling system. ATLAS has installed several upgrades they weren’t expecting to install for a number of months. The GRID computer system has undergone full scale tests.The final sector to be checked will be cooled down in August, which—if they find more leaks—may mean that the LHC could be delayed until the New Year. Related News Pick LHC restart pushed back, may not run at 14 TeV LHC repair plan points to weaknesses in original design Late start for Large Hadron Collider