Well, a very gentle sort of wham. Yesterday the Large Hadron Collider at CERN had its first collisions of protons! It is a warm start, making sure everything is working before ramping up the energies to regimes where we hope to see new physics, but it is a very exciting milestone nonetheless*. Recall that a few days back they hit the landmark of getting the machine to circulate beams again for the first time. (If you’ve forgotten what all of this is for, please search the blog for “LHC” and/or look in the related posts list at the bottom of this one.) Above right is a visual reconstruction of some of the collision data seen at the ALICE detector, and you can see more of this sort of data at CERN’s website (from where I got this graphic).
From the press release:
“It’s a great achievement to have come this far in so short a time,” said CERN1Director General Rolf Heuer. “But we need to keep a sense of perspective – there’s still much to do before we can start the LHC physics programme.”
Beams were first tuned to produce collisions in the ATLAS detector, which recorded its first candidate for collisions at 14:22 this afternoon. Later, the beams were optimised for CMS. In the evening, ALICE had the first optimization, followed by LHCb.
“This is great news, the start of a fantastic era of physics and hopefully discoveries after 20 years’ work by the international community to build a machine and detectors of unprecedented complexity and performance,” said ATLAS spokesperson, Fabiola Gianotti.
“The events so far mark the start of the second half of this incredible voyage of discovery of the secrets of nature,” said CMS spokesperson Tejinder Virdee.
So are they seeing new physics already? No. The energy that they are colliding the beams at is simply the energy at which they’ve inserted the protons into the machine in the first place (450 GeV in case you’re keeping count). It’ll be a long road of steadily increasing that energy by a couple of orders of magnitude, and also the collision rate. Then we’ll be on for seeing some new glimpses of how our universe works.
-cvj
*Thanks Karl and Esperanza!
Hooray!