The successful restart of the LHC ranks #9 on Time magazine’s list of the top 10 scientific discoveries of 2009. That’s not bad considering that the LHC only had its first collisions last week and is still some time away from having the integrated luminosity to make big discoveries. Despite this, the LHC has set new records for the highest energy particle collisions made by human kind and it was no small task to get this far.
If everything goes smoothly, we’re looking at 3.5 TeV per beam collisions in 2010, maybe going up to 5 TeV. High energies are sexy and look good for the press, but discoveries are all about finding an excess in the rate of some process (as we discussed in an earlier post, also Regina’s latest). In order to observe this excess, we need lots of data. Why is this? Suppose you wanted to know if Kobe Bryant or LeBron James has a higher shooting percentage. After just a few games, you could look at the stats but they would be difficult to trust: maybe one player had an off day, etc. But over the course of the entire season, the accumulated stats become more trustworthy.
Particle physicists measure how much data they have in “inverse picobarns.” After next year the good folks at the LHC expect to have a couple hundred inverse picobarns of data. By comparison, the Tevatron at Fermilab has recorded something on the order of inverse femtobarns, i.e. thousands of invese picobarns of data. That’s around the ballpark (conservatively) where physicists can really start looking for the subtle hints that exotic particles have been created.
What does this all mean? Well, it means that unless nature is very kind 2010 might still be a bit early for “paradigm shifting” discoveries. I should mention two things: (1) people are keeping their eyes out in case nature is this kind and (2) there’s still a lot of very important science to be done in this period (e.g. top quark mass measurements).
After 2010 the LHC will have a “long” shut down to prepare to ramp up to 7 TeV per beam collisions. That’s when the machine will really ramp up its search for things like supersymmetry, extra dimensions, dark matter, and the Higgs (if we don’t discover it sooner). Then the LHC can aim for #1 on Time magazine’s list of scientific discoveries.
[If any of my fellow US/LHC bloggers have more updated information about 2010 expectations, please correct me!]
– Flip
Tags: barn, LHC, luminosity, press
