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Earliest LHC Restart Slated For Late Summer 2009
Posted by
timothy
on Wed Nov 26, 2008 06:10 PM
from the at-least-it's-cheap dept.
from the at-least-it's-cheap dept.
gaijinsr writes "The damage done in what CERN calls the 'S34 Incident' (and what other people call a major explosion in the cryogenics system) is much more serious than originally admitted: The earliest possible restart date is late summer next year, but with some proposed improvements to avoid repetitions of the incident, it looks more like 2010. They kept this pretty quiet up to now, not the kind of information policy I would expect from CERN."
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CERN Releases Analysis of LHC Incident 149 comments
sash writes "From the fresh press release: 'Investigations at CERN following a large helium leak into sector 3-4 of the Large Hadron Collider tunnel have confirmed that cause of the incident was a faulty electrical connection between two of the accelerator's magnets. This resulted in mechanical damage and release of helium from the magnet cold mass into the tunnel.
Proper safety procedures were in force, the safety systems performed as expected, and no one was put at risk. Sufficient spare components are in hand to ensure that the LHC is able to restart in 2009, and measures to prevent a similar incident in the future are being put in place.'"
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Yay! (Score:5, Funny)
The universe is saved for a couple of more years! Now's the time to form our new national holiday "Beat the Hell out of the Atheist Murderous Universe-destroying Physicists Day".
Re:Yay! (Score:4, Insightful)
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Fortune cookie - fitting (Score:5, Insightful)
The current fortune cookie at the end of pages is somehow very fitting:
" The universe seems neither benign nor hostile, merely indifferent. -- Sagan"
Re:Fortune cookie - fitting (Score:4, Funny)
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My prediction (Score:4, Funny)
Re:My prediction (Score:4, Informative)
the Mayan calendar merely resets at that date. similar to how computers were expected to reset at y2k, it was not that they expected the world to end they just did not include dates after that much like our calendar does not include specifically year numbers for after 9999(unless you count adding a digit but in that case you would expect the current year to be specified as 02008). http://www.xkcd.com/509/ is somewhat relevant.
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Information policy (Score:5, Insightful)
They kept this pretty quiet up to now, not the kind of information policy I would expect from CERN.
Ummmm, perhaps scientists don't like to make statements that they aren't reasonably sure of? If there were still some disagreement or doubt about this timetable, I would fully expect them to keep it internal, and would be disappointed if they made a public statement prematurely. It's not like this timetable is exactly time critical today or anything...
Re:Information policy (Score:5, Informative)
This is a work funded by taxpaid dollars, so it should be kept open and transparent. The author of the article is right in this premise.
But I disagree strongly with her perception of the situation. CERN's earlier statements have only been that they did not know how long repairs would take, but that the earliest LHC could possibly restart would be late spring 2009. This is the first time to my knowledge that they have given an estimate of when they actually expect the accelerator to be ready. There was nothing hidden or hushed up about this.
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Re: (Score:3, Insightful)
Maybe they had to take some big pieces of machinery apart before making a definitive statement. That takes time.
Even worse than a late statement would be making a statement then changing it a couple of weeks later.
Re:Information policy (Score:5, Informative)
The LHC is its own prototype. Similar beam related incidents happened at Fermilab. It's shit but it happens, and they handled it dreadfully.
Some big numbers were thrown out there about how much the accident will cost, but in real terms it comes our as a very small fraction compared to overall LHC costs.
Everyone at CERN is very disappointed about it, naturally, but it's up to us now to better prepare ourselves for the new startup.
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Re:Information policy (Score:5, Informative)
You are so full of nonsense.
LHC is NOT a EU project (EU as European Union).
LHC is a CERN project and CERN is not a EU body.
CERN is an international organisation (like Interpol, WHO, UN, etc.), located on the border between France and Switzerland (Switzerland is NOT part of the EU either).
Buildings are mostly in Switzerland, while most of the tunnel is in France.
CERN predates LHC of something like 30 years.
The LHC is built in the tunnel used previously (for 10 to 15 years) by the former main CERN project (LEP: Large Electron Positron Collider).
So try and be less clueless.
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Re:Information policy (Score:5, Informative)
While the LHC is indeed not an EU project, most of girlintraining's remain valid. Politics and national pride play an important part in the internal workings of CERN, and could well explain the communication policy.
Calling people full of nonsense because they did not get some details right is not very polite, dear Anonymous Coward. Actually, there are quite a few building in Prévessin. And while CERN is definitely not an EU project, it is different from the WHO, or the UN in the sense that it has a geographic definition, it is called the European Organization for Nuclear Research. Some of the funding for CERN related projects, like the grids efforts, comes directly from the EU.
So please try to be less impolite and arrogant...
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What do you expect? (Score:5, Interesting)
The LHC has been longer in development than the WWW exists (there are screenshots around from the "first website ever" that had design drawings of the atlas detector on it.
It has happened. They got to fix it, piece by piece. Do you really need a "what cf flanges we replaced today" blog?
Re:What do you expect? (Score:5, Informative)
Karma whoring linky here [madsci.org].
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Re:What do you expect? (Score:5, Interesting)
This being said, I'd say that the LHC has already paid for itself a thousand times over.
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With the data... (Score:5, Interesting)
Most likely cause : an electric arc due to rupture of the interconnection. Unfortunately this is difficult to prove, since the whole dipole interconnect was 'vaporised' during the event!
Cut 'em some slack (Score:5, Funny)
Some Further Info (Score:5, Informative)
The beam is like small bomb. (Score:4, Insightful)
The beam would make a good weapon (if the LHC a bad weapons system).
The beam was 200 MJoules, the equivalent of 48 kilo's of TNT. That's a pretty good bomb if it should hit you.
(Note that there are 2 beams; it is not clear to me if that is the energy per beam on in total.)
Summer Blockbusters (Score:4, Funny)
Some notes (Score:5, Informative)
The initial cause of the incident was probably a bad weld in a busbar joint. But they'll never know; the entire busbar was vaporized when it lost superconductivity under load.
The quench protection system wasn't designed to properly handle a failure of the superconducting busbar between two magnets. There's an elaborate system to dump the energy from a magnet that's starting to lose superconductivity into a big resistor bank. They expected occasional problems within the magnet windings, but this failure wasn't in a winding. The quench system is being redesigned.
The cryogenic system needs many more pressure relief valves. In this event, 6 tons of liquid helium was vaporized, which is 30,000 cubic meters at 1 atmosphere. That much helium couldn't get out of the existing relief valves fast enough, sizable parts of the plumbing were damaged, and magnets were pushed off their mounts. Now that was just bad pressure-vessel design. They should have had enough relief valves or rupture discs for the worst-case scenario. That would have localized the problem. Given the huge amount of energy in the magnets, in close proximity to liquid helium, in an experimental machine, this could not be a totally unexpected possibility.
More relief valves are going in, which means the whole ring has to be brought up to room temperature and atmospheric pressure for plumbing work. Then the whole commissioning process has to be repeated, which takes months.
The tunnels are empty of people when power is on, because if all that helium vents, the air is unbreathable. But this event was big enough that it could have affected people in experiment halls at tunnel level. If this had happened during actual use, people could have been killed.
A magnet quench isn't supposed to be a big deal. Early design specs said that restarting after a magnet quench should only take a few hours. Oops.
Some random points (Score:5, Informative)
I work on one of the LHC experiments, so I'm posting anonymously.
1) CERN's communication has been lacking. Especially in deleting reports immediately after the incident on their eLog that had been open. That was a black eye on their image.
2) Plans change as more information comes in, so no one should be surprised by initial statements saying "The earliest possible date is several months" (which would be the case if no magnets needed replacing) followed by Spring '09 if everything goes well. This is now followed by Summer '09 to just repair the problems and late '09/ early '10 if remedial actions are taken.
3) CERN is changing directors in a month or so. The new director will make the decision of cautious startup vs. remediation and more aggressive startup. My expectation is the latter.
The world can wait an extra year for these results. I feel bad for the students and post-docs who are waiting for the data to emerge, though.
Whatever. (Score:5, Funny)
We will never see it work (Score:4, Funny)
LHC is obviously a doomsday machine. Turning it on will immediately destroy humankind in all the parallel universes where it works. Therefore, in the universes where we stay alive, we will always see it fail. The failure proves the parallel structure of the universe.
Re:Anthropic principle (Score:5, Interesting)
Do you actually believe that incoherent, illogical, unscientific, unprovable baloney?
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