In the evening of Saturday May 15, we have reached a new peak luminosity record of 6 1028 cm-2s-1
It took a little bit of time, but the wait was worth it. The LHC has successfully achieved its first physics run with "squeezed beams"!
ATLAS has been designed to detect rare events in high energy proton-proton collisions. ATLAS ultimate goal is to measure events as rare as one in several thousand billions, but we are modest (for the time being) waiting for the luminosity to rise.
Now that the LHC has established colliding stable beams at a center of mass energy of 7 TeV, the next step to maximize its physics reach is to provide the most luminosity possible. As Leo posted, we need to increase the number of proton - proton collisions to make sure we have a chance of seeing the physics that we are looking for. The reason for that is because different p.hysics processes have different probabilities. These probabilities are referred to as cross-sections (in a vague reference to the particle's size). If one multiplies a cross section by a luminosity than what you get is a number of events.
I was home sick today, probably from the stress of getting ready for "M-Day" (aka Media Day), more likely though I finally succumbed to the cold that had been spreading through the Control Room. As it so happened, my laptop had been in the shop because it experience an "incident" (actually I just dropped it) last Monday (the week before Media Day), and I just picked it up yesterday.
Many collisions will be needed to unveil the secrets eventually hidden at the 7 TeV energy regime.
After decades of planning. After years of delays and immeasureable amounts of patience and hard work. The physics operations of the LHC has begun!
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.