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Footage from this morning's meeting in the CERN Control Centre. The night shifters hand the accelerator over to the day shift, and CERN's Director for Accelerators and Technology announces the #RestartLHC.

The meeting at the CERN Control Centre this morning (Video: Noemi Caraban Gonzalez/CERN)


Beam 2 has now made more than 25 turns of the LHC.


An image showing a cross section of beam 2, the first beam to circulate this morning, after a couple of turns of the LHC as seen at point 8.


To check the stability of Beam 2, the operators are now allowing it to orbit the accelerator a couple of times.  


Graph showing that beam has passed through all of the LHC's 8 sectors. The higher the green peaks of the graph, the more the beam is deviating from its nominal orbit. We expect to see this graph getting thinner through the day.



The operators have just opened the last collimators for Beam 2 Anticlockwise. Beam 2 has completed its circuit of the LHC!


The atmosphere is relaxed in the CERN Control Centre as the first beam makes it rapidly through the first seven sectors.


Beam 2 is now through the ALICE experiment. Just on sector left to go!


Beam 2 is now at Point 3 on the LHC. Murmurs of approval from the operators. Shouts of "Okay - now for ALICE!" 

ALICE (A Large Ion Collider Experiment) is a heavy-ion detector on the Large Hadron Collider (LHC) ring. It is designed to study the physics of strongly interacting matter at extreme energy densities, where a phase of matter called quark-gluon plasma forms. It is about to receive the beam for the first time in 2 years. 



Another cheer! The beam has passed through the CMS detector at Point 5. 


Threading with beam 2 has gone to point 6! A cheer of approval from the LHC operators. CMS have called - they are waiting for the beam to arrive at point 5, to pass through their detector.


Success! Beam 2 is at point 7!


Beam 2, in the anticlockwise direction, will be the first to be injected today. It will be injected to the 27-kilometre LHC at point 8, home of the Large Hadron Collider beauty (LHCb) experiment and pass along this first sector to point 7. 

Beam 2, the first to be injected, will pass from point 8 to point 7 (Image: Leonard Rimensberger)




CERN Director-General Rolf Heuer arrives on scene to watch the day's action. The atmosphere is relaxed but excited as the LHC operators crowd the control hub in the CERN Control Centre. They are keeping an eye on the LHC Control Screen, which reads BEAM SETUP: INJECTION PROBE BEAM. At the bottom right of the control screen "Beam permit" is green for Beam 1 (B1) - the beam has been authorised, ready to go. 

The beams will circulate today at their injection energy of 450 GeV.


LHC operators in the CERN Control Centre


View from the CERN Control Centre (CCC) this morning.


CERN Director for Accelerators and Technology Frédérick Bordry is passing Easter eggs round the LHC Control Centre to an excited team of technicians and engineers.