Delay of the LHC

the original plan was that the lhc would do a test run in november this year, in which a proton beam would have run through the accelerator without actually being accelerated. however, because of the failure of the quadrupole magnets earlier this year, the lhc probably won't run until 2008. official notification of any delay will be made later this month. this nice article ends on the upnote that fermilab may be able to find the higgs before the lhc turns on. well, we can always hope. it sure would be a nice thing for fermilab to accomplish before the tevatron shuts down.

New York Times LHC Article

this is almost old by now, but it's a nice article written by dennis overbye at the nytimes about the LHC and its importance to the field of particle physics.

LHC Magnet Failure

this is not the sort of thing we'd like to see happening so soon before the LHC is expected to start running: on tuesday, a test of one of the accelerator's quadrupole magnets, which are used to focus the particle beam, failed miserably. here is an explanation of what happened from fermilab's john conway at cosmicvariance:

"The failure occured during a test which simulated what the magnet might experience during a “quench” which is when some part of the superconducting cable inside the magnet suddenly goes “normal” and then resists the flow of the huge current in it. This releases heat, of course, causing the rest of the superconducting material to go normal. Liquid helium boils rapidly, creating large asymmetric pressures inside the magnet cryostat. These pressures can reach 20 bar, and it was during a 20-bar test that this particular magnet failed. No one was in the LHC tunnel when it happened - it must have been quite a sight, and sound, though."

apparently, four reviews of the magnets were carried out at fermilab (where they were built) between 1998 and 2002 by experts from a number of different laboratories, yet apparently these reviews didn't address the issue of asymmetric pressures. read more about this in the fermilab statement. oh and i like this: why do physicists want to study particles? (a crucial question to ask given LHC's 3.8 billion dollar price tag.) the image above shows one of the quadrupoles being installed in 2006. (image credit: fermilab)

The Future of (Some) Scientific Disciplines

while on the seed note, let me link to this article as well, in which leaders in a number of scientific disciplines discuss where they believe their fields are headed in the next few years. notable entries by sean carroll on cosmology, lisa randall on high energy physics, and marc hauser (one of my favorite people from my year at harvard) on cognitive evolution. not surprisingly, both sean and lisa talk about the importance of the lhc and the implications for physics beyond the standard model. it's an exciting time for physicists!