Okay, so I’ve been a bit lazy updating my blog recently – actually because I’ve spent most of my time either working or sleeping (and admittedly watching the occasional movie!). Big news – I now have my access permissions to go in the LHC tunnel, that rather well known 27km long sub-atomic underground system underneath Switzerland and France.
I made my first descent into the machine on Friday morning at about 11am. Unfortunately the rest of my team was elsewhere, so I was on my own! Eventually I managed to negotiate the security door – ID badge check, Radiation Dosimeter check, standing on the plate check, waiting for the doors to close – followed by a retina ID scan, and if you’re lucky the front set of doors open and you’re inside the ‘restricted’ machine area. I think it took me about 20 tries to get through the entry procedures – this on the second day of attempting it. On Thursday I had also tried to go in, but it turns out one of my 20+ access permissions was missing, in particular the one critical for access to the LHC tunnel.
Once I’d made it to the bottom of the tunnel in the lift, I found myself in ‘Point 8’, where the LHCb detector is located. I actually visited the pit back in 2005 – however it was a bit different back then as the detector was still being assembled. Today it is unrecognisable, with a sizeable radiation shielding in place, along with the old Delphi detector from the LEP era.
I was looking for the LHC accelerator tunnel, which in theory runs right through the LHCb detector axis, I’d also brought a map of the tunnel with me. However despite some fascinating searching of the machine cavern, I couldn’t actually find what I was looking for – specifically a couple of equipment areas just off the main tunnel shaft. I have to say it was absolutely fascinating to be down in the tunnel – it’s almost like going to another planet, or being inside a space ship. There are orange safety lights everywhere, and huge ducts going back up to the surface. Even though the machine is off (otherwise it wouldn’t be safe to go down), there are all kinds of mechanical and electrical items that make clicking, buzzing and the occasional wooshing noise.
Since then I’ve been down the tunnel about 5 times, twice more on Friday afternoon and a couple of times on Sunday for some out of hours electrical testing. Highlight of that trip was visiting the Atlas experimental cavern, which must be the single most impressive scientific instrument I’ve ever seen by a factor of about 2e^23, or possibly more. I was with my boss and we were busy testing the emergency systems so didn’t have time for photos. However, here’s one I took on Friday afternoon in a technical cavern about half way between the Alice and CMS experiments.
Will post some more images of the cool stuff I saw in the tunnel later on, right now it’s time for me to eat my dinner – which would be a pizza topped with Chorizo and Bleu de Gex cheese. Delicious!