mesavoida31 karma2019-10-18 14:29:29 UTC
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mesavoida21 karma2019-10-18 10:53:13 UTC
The numbers in that link are post-upgrade, however, the one I built was still pretty amazing. When I heard about particle accelerators I thought they just threw them together once in a while. The reality is they do so every millisecond or faster. Why? Something like only one in many 10's of millions? are considered "interesting" and the rest have been seen millions of times before so there needs to be a real-time LVL 1 trigger that discards all of that junk and just saves the interesting data and sends it further up the chain to be looked at further. It used the very latest FPGA's which are Field Programmable Gate Arrays that are custom designed for such high-speed decisions ($10k per lot). They also could be reprogrammed on the fly. Look back up the comment chain for the ELI5 explanation.
mesavoida19 karma2019-10-18 10:57:20 UTC
Nothing really. I found this job quite boring outside the actual knowledge I was doing something great overall. I never got to see these things fully energized and pretty much nobody did because of safety concerns.
Besides, I worked on the detectors. The actual semi-conductor superconductor particle rings (Tevatron/Large Hadron Collider) were built decades ago. You can still do tours of Fermi lab near Chicago and see all of this stuff including the liquid helium condensers and the enormous amount of copper that went into the electromagnetics.
I tried to understand how they actually accelerate particles up the speed of light and control that many magnets in a rail-gun fashion, and the answer seemed a lot simpler than you would think. Radio waves. Control inputs that are the same frequency as an FM radio. You would have to ask somebody who actually worked on that side for more.
mesavoida15 karma2019-10-18 08:00:54 UTC
I worked LIGO a little bit and talked to some of the people that designed it. One of the issues was managing each and every cable length to compensate for the minute speed of light differences in timing. I just happen to actually look into what I think is the same controversy and also concluded that the results were flawed.
Overall the quality of the equipment there is extreme but also rats nest of hodgepodged projects. I never actually got to visit CERN but I would’ve eventually if I’d stayed on the project. I did get to visit Fermi lab though. One issue is that they hired a lot of academics and grad-students who are over-confident of their skills in soldering and mechanical engineering but lack the kind of experience I have had from doing this from the age of 4 and being trained by the best. As far as I know, our cards worked flawlessly until they were replaced recently during the shutdown. I am meticulous in my work and have never produced a flawed product or repair nor have I been shocked on the job even despite working with up to 16,000V. I never got to meet my technician counterparts in Europe, but I can assume many of them were my equals.
mesavoida9 karma2019-10-18 14:50:21 UTC
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