Incident in LHC sector 34But really, folks: these machines rarely come up quickly and problem-free. RHIC has been running for years, but people never mention that it had a very tough first year, and every start-up each year had its scary moments (including these repairs involving "warm-up" of the superconducting helium, which necessarily take weeks to months). So we should all keep our fingers crossed, but I doubt that it's time to be overly worried at this point.
During commissioning (without beam) of the final LHC sector (sector 34) at high current for operation at 5 TeV, an incident occurred at mid-day on Friday 19 September resulting in a large helium leak into the tunnel. Preliminary investigations indicate that the most likely cause of the problem was a faulty electrical connection between two magnets which probably melted at high current leading to mechanical failure. CERN's strict safety regulations ensured that at no time was there any risk to people.
A full investigation is underway, but it is already clear that the sector will have to be warmed up for repairs to take place. This implies a minimum of two months down time for the LHC operation. For the same fault, not uncommon in a normally conducting machine, the repair time would be a matter of days.
Further details will be made available as soon as they are known.
Saturday, September 20, 2008
Yeah, yeah, $700 billion is a lot of money, but the real front page news is a bit below the fold: Problems Stall Action for Collider. CERN's DG Robert Aymar email to CERN personnel tells the story more precisely: