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Second Snag This Week Could Delay LHC for Weeks
sciencehabit writes "After a transformer failure earlier this week, the Large Hadron Collider has hit another snag — and this one is much more serious. As Science reports, 'At least one of the LHC's more than 1700 superconducting magnets failed, springing a leak and spewing helium gas into the subterranean tunnel that houses the collider ... How long [repairs take] will depend in part on how much of the LHC must be warmed to room temperature for servicing. If it's only a short section, the repair could be relatively quick. But the machine is built in octants, and if workers have to heat and cool an entire octant, then the cooling alone would take several weeks."
Reader Simmeh contributes coverage from the BBC. We recently discussed the transformer malfunction at the LHC, which was a smaller problem and has already been fixed. Update - 9/20 at 12:52 by SS: CNN reports that the LHC will be out of commission for two months.
Could it be that the to-be-discovered Higgs boson particulars are causing effecting the past and causing malfunctions with the LHC's components? http://blogs.discovermagazine.com/discoblog/2008/08/11/will-the-lhc%E2%80%99s-future-cancel-out-its-past/
I'd like to know the diameter of the vacuum-insulated piping that is transporting the liquid helium for cooling. Piping large volumes of that stuff is not trivial.
more relevant wikipedia article about the implications for observers:
http://en.wikipedia.org/wiki/Many-minds_interpretation
Only minds that exist can observe; only minds that have not been destroyed by the LHC can exist. So, if the LHC really destroys the earth we'll keep observing it not functioning correctly.
To add to this pretty good explanation, quenching is a normal part of "training" a SC magnet. Basically, when the SC coil is wound, there are slight imperfections that prevent a maximal field from being obtained. So you pump a shit ton of current through the magnet after cooling it for the first time till it quenches. As you put field, you actually are changing the winding configuration ever so slightly, as the field generated by the magnet can actually exert on the force wires containing the current. This process is repeated several times to maximize the attainable field, and make it homogeneous as possible, etc.
The only other problem is that unplanned quenches can also damage the magnet. That is unlikely in this case, but I have a dead hulk of a 9T in my lab to prove that it can happen. To this day, I don't know what went wrong, but my guess is that there was damage at the point that current enters and leaves the system during field changes. Hopefully this is not the case at the LHC, and they can be back up and in business ASAP.
This makes me think of the great SF story "Doomsday Device", by John Gribbin (Analog, Feb. 1985 -- unfortunately not available online, AFAIK). In that story a powerful particle accelerator seemingly fails to operate, for no good reason. Then a physicist realizes that if it were to work, it would effectively destroy the entire universe, by initiating a transition from a cosmological false vacuum state to a lower-energy vacuum state. In fact, the accelerator *has* worked; the only realities the characters experience involve highly unlikely equipment failures. (Thus, a many-worlds physics is shown to be correct.) It's further revealed that the world has been "anthropically steered" in the past by arranging for it to be destroyed when things are not going well.