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Europe's LHC To Run At Half-Energy Through 2011
quaith writes "ScienceInsider reports that Europe's Large Hadron Collider will run at half its maximum energy through 2011 and likely not at all in 2012. The previous plan was to ramp it up to 70% of maximum energy this year. Under the new plan, the LHC will run at 7 trillion electron-volts through 2011. The LHC would then shut down for a year so workers could replace all of its 10,000 interconnects with redesigned ones allowing the LHC to run at its full 14 TeV capacity in 2013. The change raises hopes at the LHC's lower-energy rival, the Tevatron Collider at Fermi National Accelerator Laboratory in Batavia, Illinois, of being extended through 2012 instead of being shut down next year. Fermilab researchers are hoping that their machine might collect enough data to beat the LHC to the discovery of the Higgs boson, a particle key to how physicists explain the origin of mass."
Does this news mean we now only have to be half afraid that they're going to create a black hole that will destroy the Earth?
at (apparently) no one being fired for designing interconnects that only allow the LHC to run at 1/2 power? I may not be a scientist, but shouldn't a design cover the requirements? Then, to lose a year's work on top of that, and no one is getting their wrist slapped or even sued?
Impetuous! Homeric!
7 TeV is still more than 3 times Fermilab's total collision energy.
This more conservative ramp up is probably smart given the previous problems with equipment failure on the LHC. This will allow the systems to be tested thoroughly before going to max capacity.
I'm scared for all the half-lives at risk.
But what about all the counter-strikes and the portals?
The Big Deal about the LHC isn't just the energy. It's also that it allows for a much higher collision rate than the Tevatron. Even if you only run the thing at Tevatron energies, it's possible that it can collect as much data in a week as the Tevatron could in years.
When the LHC guys down the hall show up tomorrow I'll have to ask them about the planned luminosity in the first year of running.
Uh, HEL-LO?!! Have you guys forgotten that the world is going to end in 2012?!! I think you might want to ramp it up all the way in 2011...just in case.
"Klaatu, verada, necktie!" -Ash
If the LHC was designed properly, run the friggin' thing. If not, fix the friggin' thing.
Did you RTFA? That's exactly what they're doing. It takes time to come up with a proper fix, but while you're coming up with something, why not use the thing? Even at a fraction of its energy, the LHC is the most advanced accelerator in the world. It would be a shame to just let it sit there.
The beam energy at 7TeV is 362 megajoules. This is about the energy that you could get by maxing out a household mains connection (230V 20A) for one day, or about the energy content of 11 liters of gasoline. Quite a bit, but not huge at energy scales.
Of course, the beauty of the LHC is that it accomplishes this energy in the form of a particle beam circling the collider at near the speed of light. This means that the power of the beam is about 4 terawatts if my math is right, so it could power about 3300 DeLorean time machines (not for very long, though). Keep in mind that this power is circling endlessly in the LHC, so it isn't being consumed - the actual electric power consumption to run the whole LHC is "only" about 120 megawatts.
I seem to have heard this argument before.
The Apollo fire. The loss of the Challenger. Repairs to the Hubble.
I seem to have heard this misconception before. The Apollo fire wasn't because of a cutting-edge project taking technical risks, or making a considered judgement to accept smaller safety margins in exchange for reduced costs.
Having a mixed-gas oxygen-nitrogen atmosphere in the Apollo capsule would have increased the internal capsule pressure in orbit, requiring a beefier structure and more weight. More dangerously, it would have required the development of suitable partial-pressure sensors for the precise measurement of oxygen levels within a mixed-gas environment. That would have constituted a technical risk. In contrast, the system used in the original Apollo design required only a simple pressure gauge to ensure sufficient oxygen for the crew.
Moreover, in orbit the Apollo capsule internal pressure would be only about 5 psi - about a third of an atmosphere. While that pressure of oxygen is sufficient to support combustion, it isn't dangerously high, and all of the materials used aboard Apollo were tested for fire safety under those conditions. The big problem was that on the launch pad, the capsule contained a full atmosphere of oxygen (the excess pressure would be bled off as the capsule ascended to orbit). Nobody thought to test under those conditions. Even then, there's at least some evidence to suggest that it was the astronauts' webbing the capsule with large amounts of Velcro that allowed the fire to spread so rapidly.
Finally, the earliest design for the Apollo capsule hatch opened outwards and was equipped with explosive bolts for rapid egress. It was at the insistence of astronaut Gus Grissom (who may have been the victim of premature triggering of such a system on his Mercury capsule) that the hatch be replaced with an inward-opening, 'plug' design that lacked explosive bolts.
Both previous manned U.S. space capsules (Mercury and Gemini) had used essentially identical pure oxygen atmospheres, without concern and without any problems. Did they get lucky? Absolutely, in retrospect. Should the Apollo engineers have recognized the dangers that their predecessors had overlooked? Probably. Was the fire the result of taking 'technical risks' on a 'cutting edge project'? Nope. They thought they were sticking with a simple system that had worked for years, and didn't want to asphyxiate an astronaut by fiddling with something reliable.
~Idarubicin
In an equally optimistic point of view, if Higgs boson is later shown to not exist, the Tevatron Collider can claim that it was able to not find it before the LHC!
The failures, or rather misdesigns/misbuilds, are in "copper bus bars". These effectively act as shorts across the superconducting electromagnet coils. Since the coils are normally superconducting (when at cryogenic temperatures), the short does nothing. But if the coil gets ever so slightly above its critical temperature, it ceases to be superconducting. At that point, it still has very very low resistance, but the current through it is so enormous that it heats up rapidly. When it gets to a certain temperature, its resistance becomes comparable to the resistance of the copper bus bar shorting it, and the current starts to flow more and more through the copper, thus protecting the superconductor from getting too much hotter. At least, that's what is supposed to happen.
What is wrong is that some of the solder joints for the bus bars are not good, and have too high of a resistance. A higher resistance in the bus bar system means a higher superconductor temperature before the current starts to flow through the copper, and in the end, this means damage to magnets.
I'm not sure what level of testing was done, but building a short segment and testing it up to slightly above design spec is probably not really feasible. In order to get the particles to the eventual energies, you need the whole ring to be in working order, because it takes tons of complete circles around the ring to accelerate the particles. Injection from the SPS to the LHC occurs at 1/14th the design beam energy, and the LHC ring takes it up from there.
Even if you could inject 7 TeV protons into a short segment of the ring, you'd still not be able to get the design beam intensity that way, because you don't have all 2000+ bunches ready for injection at once.
You could run the magnet intensities up to what is needed to bend a beam in a tight enough circle at high enough energies even without any actual beam in there, and this was probably done. However, quenches (magnets getting above critical temp) happen principally because of the beam. The beam loses particles and energy at a fairly high rate due to a variety of effects, and all those particles and all that energy goes into heating something, usually the bending magnets. I suppose you could do a deliberate quench by playing with the cryo, though. Perhaps that was done, and we were unfortunate enough to have tested only good subsystems this way.
As you may have guessed, I am a particle physicist (on CDF), but not a beams engineer. So, some of the above is guesswork, but I hope I've been able to relieve some of your ignorance.
SIGSEGV caught, terminating
wait... not that kind of sig.
Oh there's so much more. The sinking of Columbus' ship Santa María comes to mind, the death of Marie Curie by cancer, the risks Franklin took when proving lightning was electricity and the murder of William Bullock by his printing-machine. Here are some more: http://listverse.com/2008/12/14/10-inventors-killed-by-their-inventions/
The thing is, the greatest discoveries very often come at a great risk. The risk-averse culture than has steadily been introduced since, say, the 1970s probably greatly holds back mankinds progress. No longer are victims of cutting-edge technologic failures hero's, instead their designers are the victim of outrage and lawsuits. This makes me very sad. Risks are not something bad, risks are things taken by brave people. Very often those people are the ones responsible for great leaps in mankinds progress.
Therefore the argument you quote is not just a good argument, it is a great argument. Wimps that cannot handle it should stay away from it and keep their mouth shut.
0x or or snor perron?!