CERN's Large Hadron Collider has finally started colliding two 3.5-TeV circulating beams of protons together to produce 7-TeV collisions and the official start of the LHC research program.
The collisions above occured at the LHC ,with a couple hundred thousand collisions taken in the first hour.
The collisions almost didn't happen when a power supply tripped and had to be reset says Steve Meyers , CERN's director for accelerators and technology. The new safety system that had been installed after technical difficulties in 2008, then the system was shut down . New protons were quickly injected back into the ring after the problem was corrected.Research teams at the four LHC experiments—ATLAS, ALICE ,CMS and LHCb—say that data delivered from their detectors look good. LHC Project leader Lyn Evans cautions however, that it will take some time to run the collider up to maximum efficiency.
A LONG RUN
CERN will run the LHC for 18–24 months with the objective of delivering enough data to the experiments to make significant advances across a wide range of physics. As soon as they have calibrated the detectors by "rediscovering" the known standard model particles , the LHC experiments will start the systematic search for the Higgs Boson . The latest data from Fermilab suggest however, that the Higgs will not be discovered in this first datarun but will require higher collision energies.
For supersymmetry, ATLAS and CMS will each have enough data to double today's sensitivity to certain new discoveries. Experiments today are sensitive to some supersymmetric particles with masses up to 400 GeV. An inverse femtobarn at the LHC pushes the discovery range up to 800 GeV.
For supersymmetry, ATLAS and CMS will each have enough data to double today's sensitivity to certain new discoveries. Experiments today are sensitive to some supersymmetric particles with masses up to 400 GeV. An inverse femtobarn at the LHC pushes the discovery range up to 800 GeV.
SHUTDOWN AND UPGRADE
Following this run, the LHC will shutdown for routine maintenance, and to complete the repairs nessecitated by the incident of 19 September -when an improperly soldered splice connecting two superconducting cables failed- and the consolidation needed to reach the LHC's design energy of 14-TeV.
Traditionally, CERN has operated its accelerators on an annual cycle, running for seven to eight months with a four- to five-month shutdown each year but because the cryogenic machine operates at very low temperature, the LHC takes about a month to come up to room temperature and another month to cool down. A four-month shutdown as part of an annual cycle no longer makes sense for such a machine, so CERN has decided to move to a longer cycle with longer periods of operation accompanied by longer shutdown periods when needed.
Following this run, the LHC will shutdown for routine maintenance, and to complete the repairs nessecitated by the incident of 19 September -when an improperly soldered splice connecting two superconducting cables failed- and the consolidation needed to reach the LHC's design energy of 14-TeV.
Traditionally, CERN has operated its accelerators on an annual cycle, running for seven to eight months with a four- to five-month shutdown each year but because the cryogenic machine operates at very low temperature, the LHC takes about a month to come up to room temperature and another month to cool down. A four-month shutdown as part of an annual cycle no longer makes sense for such a machine, so CERN has decided to move to a longer cycle with longer periods of operation accompanied by longer shutdown periods when needed.
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