After ramping of the beams to 3.5 TeV and tuning, final checks, and some emotions due to an unforeseen beam dump, the 7 TeV collisions finally appeared on the on-line monitors of the ATLAS Control Room.
So how will this whole "First 7 TeV Collisions" event happen? Well, here is my (somewhat naive) understanding of what will happen.
This Tuesday, if all goes according to plan, will mark the end of a very long journey for many High Energy Physicists. The first 7 TeV Collisions will signal the end of the the commissioning period of the LHC and its experiments.
It has been a BUSY weekend! The LHC has been working around the clock get the machine commissioned, and ATLAS has been enjoying the many Firsts that have resulted.
At approximately 2:40 am Central European Time, ATLAS saw particles from the LHC for the first time in 2010. As in previous LHC turn-on periods the first thing we see are beam splashes from the LHC beams as they slowly thread the beam through the LHC ring for the first time.
The Control Room is quiet. The configurations are set. The trigger menu is uploaded. The shifters are ready. All that is left is for the LHC to deliver beam.
High Energy Physicists have been waiting for many years to see the LHC turn on. Now that it has been turned on, the network of physicists around the world have quickly been harnessed. It can be considered a phase transition in particle physics.
On Sunday December 6, 2009 at 8.00 the ATLAS Pixel Detector has measured, for the first time, tracks emerging from LHC collisions. It has been a very smooth start.