Large Hadron Collider quadrupole superconductor electromagnets for directing proton beams to interact. Image via WikipediaPretty astonished at this story about how a piece of bread, supposedly dropped by a bird, has shut down the Large Hadron Collider, the world's most powerful particle accelerator.
The article's source said,
machinery on the surface - the LHC accelerator circuit itself is buried deep beneath the Franco-Swiss border outside Geneva - had suffered a fault caused by "a bit of baguette on the busbars", thought perhaps to have been dropped by a bird.And so what? What would that mean, if the magnets were unable to fulfill their function?
As a result, temperatures in part of the LHC's circuit climbed to almost 8 Kelvin - significantly higher than the normal operating temperature of 1.9, and close to the temperature at which the LHC's niobium-titanium magnets are likely to "quench", or cease superconducting and become ordinary "warm" magnets - by no means up to the task imposed on them. Dr Tadeusz Kurtyka, a CERN engineer, told [The Register ("Biting the hand that feeds IT")] that this can happen unpredictably at temperatures above 9.6 K.
Well, says the article in The Register . . .
At the moment there are no beams of hadrons barrelling around the huge magnetic doughnut at close to light speed, but when there are, each of the two beams has as much energy in it as an aircraft carrier underway. If the LHC suddenly lost its ability to keep the beam circling around its vacuum pipe, all that energy would have to go somewhere - with results on the same scale as being rammed by an aircraft carrier.????!!!! "Being rammed by an aircraft carrier"? What would suffer the effects of being rammed by an aircraft carrier? And what kind of "ramming" are we talking about? A head-on collision? A side-long glance?
And at what speed would this "equivalent" aircraft carrier be going when it hit?
According to The Register which, in turn, was relying on information provided by Dr Mike Lamont, "LHC Machine Coordinator" at the CERN control center:
Had this week's feathered baguette-packing saboteur struckReassuring, wouldn't you say?
. . .with a brace of beams roaring round the LHC's magnetic motorway, the climbing temperatures would have been noted and the beams diverted - rather in the fashion that a runaway truck or train can be - into "dump caverns" lying a little off the main track of the LHC. In these large artificial caves, each beam would power into a "dump core", a massive 7m-long graphite block encased in steel, water cooled and then further wrapped in 750 tonnes of concrete and iron shielding. The dump core would become extremely hot and quite radioactive, but it has massive shielding and scores of metres of solid granite lie between the cavern and the surface. Nobody up top, except the control room staff, would even notice.
This whole process would be over in a trice, well before the birdy bread-bomber's shenanigans could warm the main track up to anywhere near quench temperature. Should the magnets then quench, no carrier-wreck catastrophe would result.
According to Lamont, provided the underlying fault didn't take too long to rectify, the LHC could be up and beaming again "within, say, three days" following such an incident.
Meanwhile, back on the Popular Science blog where I first read about the "birdy bread-bomber," as The Register so humorously described the incident, readers question the entire affair.
Writes one: "I don't understand how a 'section of outdoor machinery' can be so sensitive to something being on it. Isn't this going to happen all the time?? Rain will fall on it, leaves will blow on it, birds will crap on it, etc. Shouldn't it be covered if it is so delicate?"
And another replies, reasonably: "Even if normal precautions are taken against leaves and other normal material found outdoors, a piece of bread may overcome them. First, the bread may be soft enough to mold itself to the grill if enough suction is being applied. Then the air will dry the bread effectively making it into a form fitted block. Less air flow means less cooling effectiveness down the line. Again, a cascade affect could become possible depending on how much other devices rel on that source for cooling - either as a primary source, or secondary or tertiary.
"Since a critical component in a machine does NOT have to be large, it may not require a lot of cooling. In these cases, a piece of bread would indeed be enough to cause a failure such that the entire operation has to be shut down to ensure nothing is damaged, or that a more serious problem is not culpable."
"While your analogy to a radiator is persuasive from an engineering perspective, it does not hold water from a design perspective," writes a third.
The more critical the component the more redundant it must be, period. Even in aircraft, where space and weight are of critical concern, some effort in this regard is made."Talk about a design flaw!" writes a fourth commenter. "You'd think that the brilliant people in charge of accelerating imperceptible subatomic particles would at least consider bird-proofing the place."
But and where space, weight, and apparently money, are no object, double, triple, dodecaduple redundancy should be of paramount concern, especially for mission-critical components exposed to the elements.
Atomic reactor design is a good example here, and I defy you to find a commercial power generation facility with a non-redundant heat regulator, much less one exposed to the elements in a way that a piece of toast can cause mission failure.
And let's not even get started about what this says about the maintenance regime that allowed such a critical component not to be monitored in a way that averted thermal abort.
This whole thing smacks of nothing more or less than old-fashioned incompetence, in design, implementation, and operation. Nothing new, just rendered relevant because of the sums involved.
Agreed, suggests a fifth:
You guys may all think it quite implausible that a piece of bread could shut this thing down, but there have been some serious inconsiderations from the designers.On a more humorous (???) note, however:
In Aug2009 they found a family of rats inside the tube of the accelerator where it is supposed to be a vacuum void of particles... yet a whole nest of rats?! Come on!
I think this thing is one huge money trap.
Billions spent on a "promise" as so often is the case with scientific research. And they will "produce" false results to support their theory that got them all this government money in the first place just so they can screw around for another year. It would be like an animal exterminator breeding rats and releasing them in the community so he can get more work.
Personally, I LOVE SCIENCE, I LOVE the idea of what we MAY be able to discover, but there comes a point where you must ask yourselves, "is this really financially necessary at all? If you prove even 1/2 your theory, would it have been worth the billions and billions spent and to yet be spent? What results/benefits will we realize within the next, say, 50 years, from our billions spent, should you even find what you're looking for?"
Obviously, this bird has been talking to the woodpeckers that attacked the Space Shuttle external tank, or the other woodpeckers that stopped a Lockheed Martin laser test -- perhaps relatives of the vultures that got roasted by STS-114. Clearly, Hitchcock was right, and the birds are retaliating against all high technology!And, finally:
The bird's briefing:--Actually, you can find plenty more comments like these--some humorous, some sad, some alarmist, some angry--where these came from. . . .
The approach will not be easy. You are required to maneuver straight down this trench and skim the surface to this point. The target area is only two meters wide. It's a small thermal exhaust port, right below the main port. The shaft leads directly to the reactor system. A precise hit will start a chain reaction which should destroy the station.