Friday, February 12, 2010

New Delay at the LHC and More Questions for the Tevatron

Looks like the LHC will not run at 10 TeV as originally anticipated during this run. It will continue at 7 TeV through 2011, and then go on a year-long repair hiatus with the hope of ramping to its maximum design energy when it gets back in 2012.

Strangely enough, those working at the Tevatron aren't gung-ho on trying to push for the Tevatron to run on into 2012.

Curiously, though, Fermilab physicists did not immediately clamor to run their 27-year-old Tevatron collider for an extra year through 2012. That contrasts to last year, when in response to a delay to the LHC, Fermilab scientists pushed hard to run the Tevatron through 2011, a move the U.S. Department of Energy (DOE) supports (Science, 20 February 2009, p. 993). This time, Fermilab physicists say an extra year's worth of data might not be worth the expense. "It's not like we're rushing out and saying ‘We want to run in 2012!’" says Fermilab's Dmitri Denisov, co-spokesperson for the 510-member team working with the D0 particle detector. "But we want to keep the possibility open."

Even at 7 TeV, there's plenty of physics to be done at the LHC. Already there are indications that they are seeing a few unexpected things. So there's plenty to be done in the next couple of years at this energy scale.



s.espo said...

I may be totally off here, but I could have sworn that just the other day I read a peice about the LHC running at 3.5 TeV through the end of 2010, than it going on a year-long hiatus and than possibly ramping it up to 7 TeV... Am I mistaken?

ZapperZ said...

Maybe 3.5 TeV per beam, making the center of mass energy of 7 TeV?


Michael said...

Yes, we will have collisions at a center-of-mass energy of 7 TeV.

An important point is the decision by the Director General to run long enough that each experiment accumulates an integrated luminosity of 1 fb-1. This is a lot of data, and should allow CMS and ATLAS to surpass handily the sensitivity of D0 and CDF to most signals of new physics, the most important exception being the Higgs boson at low masses. Concerning running at 7 TeV instead of 10 TeV, the cost is roughly a factor of two in integrated luminosity for most standard model processes, so we can do much better measurements with 1 fb-1 at 7 TeV than with 0.2 fb-1 at 10 TeV. The data sets become roughly equal when you consider the production of new heavy states, such as squarks and gluinos, leptoquarks, extra gauge bosons, etc.

s.espo said...

You're correct, sir! I went back and searched for the article and it turns out that it did say "per beam." Thanks for the clarification.