Large Hadron Collider Struggling

Writing in the NY Times, Dennis Overbye covers the birthing pangs and the prospects for CERN's Large Hadron Collider (which we have discussed numerous times). "The biggest, most expensive physics machine in the world is riddled with thousands of bad electrical connections. [And] many of the magnets meant to whiz high-energy subatomic particles around a 17-mile underground racetrack have mysteriously lost their ability to operate at high energies. Some physicists are deserting the European project, at least temporarily, to work at a smaller, rival machine [Fermilab's Tevatron] across the ocean. ... Technicians have spent most of the last year cleaning up and inspecting thousands of splices in the collider. About 5,000 will have to be redone... Retraining magnets is costly and time consuming, experts say, and it might not be worth the wait to get all the way to the original target energy [of 7 TeV]. Many physicists say they would be perfectly happy if the collider never got above five trillion electron volts. Dr. Myers said he thought the splices as they are could handle 4 [TeV]. 'We could be doing physics at the end of November,' he said in July, before new vacuum leaks pushed the schedule back a few additional weeks. 'It's not the design energy of the machine, but it's 4 times higher than the Tevatron,' he said."

Re:Magnets

[Rei]

Yes, you can store energy in strained magnetic fields -- so-called "spin batteries" [sciencedaily.com]. But it's poor energy density. Magnetic "batteries" are still trying to get up to the energy density of supercapacitors, which are in turn still trying to get up to the density of lead-acid batteries, which have been left in the dust by techs like lithium ion batteries. But it's a very new tech, so we'll have to see where it goes.

Re:Don't Settle

[Late Adopter]

Aside from the electrical connections, the magnets need to be trained to reach the fields necessary to sufficiently bend a 7TeV beam. The last talk I heard on the status of the magnets was that this was a very non-linear effect. We could probably get to 5, 5.5 with not that much difficulty (again, when the electrical connections are repaired)... but even getting to 6 will take *quite* an investment of down-time. The cost/benefit curve has a very clear kink in it.

Re:Lazy Europeans

[spire3661]

Sigh, typical American 'work yourself to death' mentality...I say this as an American.....

Re:Conspiracy

[Anonymous Coward]

Designs that CERN (as well as KEK and FNAL) engineers signed-off on repeatedly. Simply what happened is that they tried to cut costs too much and did not use enough and strong enough material for bracing because they did not correctly predict the magnitude of the twisting that would take place in a bad quench (little twisting mostly compression was predicted). All the engineers from every institution that looked into it missed that, and missed that on more than one occasion each time they approved the designs and early prototypes.

I'll add that the - no BS, this is what happened, and why - from the DOE and FNAL contrasted very sharply with the CERN counterparts' which was largely keeping pictures and info secret (until the official and very carefully worded report) and passing blame on everyone else. A coworker of mine nearly lost his job when he sent an email around with a few pictures of the damage. That contrasts very much with the 9 o'clock and 4 o'clock meetings at FNAL where we routinely are shown pictures of damaged equipment when the shit hits the fan here.

Re:5000 bad joints != cutting edge, It's ineptitud

[mako1138]

The connections are between copper bus bars. Superconducting material is typically clad in copper and it's the copper that gets soldered together. The joints need to have a resistance of less than 25 nano-Ohms, which seems to be the difficult part.

http://gordonwatts.wordpress.com/2009/07/05/energy-vs-power-vs-heat-vs-oh-no/ [wordpress.com]