ATLAS is about to check one more particle off of its Standard Model (SM) checklist. Namely the top quark. This famous quark is perhaps one of the most complex of the SM particles.
Do you hear that? The incessant typing? The coffee machines vending cup after cup? If you go to Building 40, or Building 32, Building 188, or to any one of the many graduate student offices around the world, you will hear the tap of key boards, the whir of disk drives, and even the occasional heated civil discussions with "elevated" voices.
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"!
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.
After decades of planning. After years of delays and immeasureable amounts of patience and hard work. The physics operations of the LHC has begun!
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.