Ok - so here are some videos I took on the 11th June last week, specifically for the purpose of showing you guys what the LHC and the CMS experiment are like
Apologies in advance as they are very shaky as I was in a rush. I was supposed to be working in the control room at the time but I sneaked out briefly and took a quick tour with my digital camera
The videos are all in MP4 format.
Some background: The CMS experiment is one of the two main "general-purpose" particle detectors on the LHC synchrotron ring. It's at "Point 5" on the ring, which is just outside a small village in France called Cessy, and is on the other side of the ring from the main CERN site which is in Geneva.
So.. the first video is the CMS Control Room at Point 5, before I snuck off to take a look around. As you can see, it has a hell of a lot of monitors...:
CMS Control Room
Next video is in the huge surface construction hall where the CMS detector was put together. To give you some idea, CMS is the size of a 4 or 5 story building, and weighs in at 15,000 tons. Last year, they finished the construction on the surface, and lowered it in several slices down the hole behind the green fence at the end of the video. This hole leads 100 meters underground to the CMS experimental cavern, which sits on the LHC synchrotron ring.
CMS Surface Construction Hall
The last video starts just after I've taken the lift 100 meters down below ground, and I'm just about to come out in the CMS service cavern, which is called USC55. USC55 hosts the trigger and data acquisition electronics, cooling services, etc, etc, and a hell of a lot of cables. At one point I nearly trip over a table and chair...
After taking a random walk around USC55, I then head down towards UXC55 - the CMS Experimental Cavern. Just as I head out of a green door (and you see me cheesily talking to the camera), you'll see a red gate with a no-entry sign on. This tunnel leads to the LHC synchrotron tunnel proper, which I'm not allowed down anymore as they are cooling it to ~1 Kelvin with large quantities of liquid helium at the moment. Lots of liquid helium = dangerous if it gets loose in an enclosed space.
Once inside UXC55, you'll see a big green thing pointing into a big red disk. The big red thing is the end of the CMS detector, and the green thing is the forward shielding required to protect the magnets down stream of UXC55 from beam collisions. The tiny yellow bit between the red disk and the green shielding is the beam pipe.
I then take a very shaky walk around the detector. You'll see some gray scaffholding from time to time... this will be removed in a few weeks, and the red disks all pushed together to "close" the detector. At the end of the video, I point the camera upwards and you can see the hole that leads up to the surface construction hall that I showed you at the end of the second video.
CMS Underground Halls
Enjoy!