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LHC Shut Down By Transformer Malfunction
Ortega-Starfire writes "A 30-ton transformer in the Large Hadron Collider malfunctioned, requiring complete replacement on the day the LHC came online. No one at CERN reported any problems, and they only released this data once the Associated Press sent people to investigate rumors of problems. I guess it's hard to just sweep a 30-ton transformer breaking under the rug."
More than meets the eye! I guess the Decepticons don't want us to advance our knowledge!
Browsing at +1 - no ACs, I ignore their posts. So refreshing!
I bet it was Omegatron!
Skip ------ See the latest from http://www.anArchyFortWorth.com
Gordon, what have you done?!?!?!
If you can read this, I forgot to post anonymously.
It's a big, complicated machine - shit breaks. It gets fixed. I wouldn't worry about it unless you're waiting for beam time.
"Physics is to math as sex is to masturbation." -R. Feynman
It would be hard to sweep a 30-ton transformer under a rug, unless there is a black hole under said rug.
You don't make the poor richer by making the rich poorer. - Winston Churchill
several to go.
Well ALICE, let's see how deep the budget hole goes...
The Hacker's Guide To The Kernel: Don't panic()!
Can one of you physicists tell me how 4.5 Kelvin is different from 2 Kelvin, operationally?
At 2 K, adding a given amount of energy makes the entropy of the system go up 2.25 times as much as it would at 4.5 K. :)
Just in case anyone else misread the headline, there's a vas deferens between the Large Hadron Collider and the Large Hardon Collider.
Lipstick.
What with, you know, most of the world's population thinking that day was the critical "black-hole" day.
Whilst I'm sure that is beneficial for CERN in the context that most people will be completely unaware on the day that full speed collisions are truly started, I do not for one moment think the media had that intention. A publicised failure would only serve to increase people's prejudice.
I record my sleeptalking
After it was started up Sept. 10, scientists circled a beam of protons in a clockwise direction at the speed of light. They shut that down, then turned on a counterclockwise beam.
Now, accelerating a proton to the speed of light seems to me impossible, given that they are in a vacuum. But if they can do that, then the other interpretation is possible. It was the scientists who were circling at the speed of light, round say, a little beaker of protons. I'd like to commend whoever shut them down, then anti-beamed them to restore reality.
If you read TFA, you discover that it, but not the provided summary on /., says it was news to nobody in the field that something broke. What's not said here, but said in TFA and far more worthy of mention, is that they replaced it and were running again the next day, well before AP even inquired. Falling prey to the cheap journalistic gimmick of awfulism, are we?
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
True, but if they're real scientists they'd figure out it's easier to sweep the black hole under the 30-ton transformer. When done, cover up with rug.
I used to come to slashdot for the summaries. Then the community grew and it was the comments that drew me here. But now, I just come for the tags.
You folks crack me up.
Carry on.
I don't know how you do it. It never works for me.
I could've sworn I left my favorite rug on top of the black hole in the living room the other day but, crazy as it sounds, it seems to have just disappeared. I'd swear on a stack of bibles that's where I left the dang thing and you know it didn't just grow legs and walk out of the house.
Well, I haven't the faintest idea how the damn thing is cooled, but helium becomes superfliud at 2.17K (iirc). It effectively loses all of its viscosity and becomes far more thermally conductive. At 2K its a superfluid, at 4.5K its not. Cool stuff, but I don't know if it matters, I don't know squat about the LHC. (see what you get for asking a question on /.?)
Is it just my observation, or are there way too many stupid people in the world?
It's a fairly standard measurement for mass, though. Transformers have mass, so it's perfectly applicable, especially when you are trying to underscore the massiveness of the piece of equipment in question, rather than its functional capability. If the person writing the article/summary wanted to underscore the cost of the unit, he might have measured it in US dollars. That's what journalists do: describe things in terms their readers might understand or care about. And most of their readers aren't pedantic electrical engineers.
Can one of you physicists tell me how 4.5 Kelvin is different from 2 Kelvin, operationally?
The magnets they use to shape and steer the beam require about 12,000 amps, so they use superconductors. Between 2K and 4.5K, the superconductor undergoes a phase change and becomes non-superconducting, and the resistance goes from zero to not zero all of a sudden. The 12,000 amps suddenly produces an incredible amount of heat (P=I^2R) which drastically increases the pressure from the liquid He. That much pressure means the He needs to escape (violently), causing all sorts of trouble. It's called a 'quench.'
"A 30-ton transformer in the Large Hadron Collider malfunctioned, requiring complete replacement on the day the LHC came online."
This news must have traveled in time - because the LHC doesn't come online until sometime next summer. Right now, its in the middle stages of a months long startup and calibration sequence.
Not to mention that stuff breaks during the startup of complex machinery, doubly so for one of a kind complex machinery.
The maximum magnetic field you can put on a superconductor depends on temperature. You can operate a superconducting magnet with a stronger magnetic field at 2 Kelven instead of 4.5 kelvin. Also, below 2.17 degrees kelvin, helium becomes super-fluid and has better heat conductivity - this is important in some applications. For alternating fields (like microwaves) superconductors are not perfectly superconducting, they have a bit if residual resistance. This resistance decreases as the temperature goes down.
They have day-to-day log of the activities at https://lhc-commissioning.web.cern.ch/lhc-commissioning/dailynews/index.htm I didn't have any problems finding this logs at the LHC website.
Transformer outage and cryogenics breakdown is logged on September 13. They were not 'rumors'.
I refuse to use
The used superconductors are good well above 4K (although with decreased maximum saturation).
The main point is that they want their helium to be superfluidic, as otherwise it would be impossible to direct the heat over the many km needed (if their were bubble formation in the dewars).
With superfluidic helium, heat resistance also drops nearly to zero(as we are in the real world, it cannot be zero. But heat conductivity increases by many magnitudes, and bubble formation is eliminated). That way, they can keep heat gradients along the whole ring well below 1K.
HI O WISE PRINCE. WHT TOOK U SO DAM LONG?
The webcam is a great source of information on CMS :), but if you want to know the status of the LHC, check the following links:
The current status of the beam can always be viewed here
All other status informations are linked from here
So maybe they didn't make a press release, but perhaps journalists should be smart enough to find these pages instead of claiming conspiracies?