A joint Fermilab/SLAC publication

LHC finishes 2011 proton run


Operators emptied the LHC of protons in the last beam dump of 2011 on Sunday. Image: CERN

The Large Hadron Collider guided beams of protons along a collision course for the last time this year on Sunday, Oct. 30.

During the LHC's 2011 run smashing protons into other protons, the machine produced 400 trillion collisions, CERN announced in a press release today. The LHC ran for about 180 days and delivered almost six times as much data as originally expected for the year. The CMS and ATLAS general-purpose experiments collected more than 5 inverse femtobarns of data.

This week, LHC operators will test various aspects of the accelerator and detectors to prepare for future runs. Then they will get ready for four weeks of lead-ion collisions. In the meantime, experimentalists will continue analyzing data from proton-proton collisions in the hunt for new physics.

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