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View Full Version : Really Bad News: LHC to be Switched Off Until Spring 2009



Fraser
2008-Sep-24, 01:00 AM
First there was a glitch with one of the huge 30-tonne transformers causing a delay of a few days, then a quench leaked a tonne of helium coolant into one of the tunnels, forcing a two-month shutdown while repairs could be made. Brace yourselves for some more bad news. In a statement released by CERN [...]

More... (http://www.universetoday.com/2008/09/23/really-bad-news-lhc-to-be-switched-off-until-spring-2009/)

Abbadon_2008
2008-Sep-24, 02:37 AM
Oh, I'll bet the CTs are having a hey-day with that.

So what's the Shadow Gov't REALLY doing with the LHC?

cjameshuff
2008-Sep-24, 04:23 PM
First there was a glitch with one of the huge 30-tonne transformers causing a delay of a few days, then a quench leaked a tonne of helium coolant into one of the tunnels, forcing a two-month shutdown while repairs could be made. Brace yourselves for some more bad news. In a statement released by CERN [...]

More... (http://www.universetoday.com/2008/09/23/really-bad-news-lhc-to-be-switched-off-until-spring-2009/)

Fortunately, it's not really all that bad. The problem isn't that severe, it just requires warming up that section of the LHC before they can work on it. They were planning to shut down for the winter in order to train the magnets up to full strength, this just means they will do so a bit earlier than expected.

The training process, from what I've read, involves repeatedly doing controlled quenching and re-cooling the magnets to work them up to their full strength. By spring, the magnets will hopefully be at full strength and more reliable, and they had a chance to verify that most of the other systems are working, and actually inject and circulate beams. The sort of problem that would be really hard and expensive to fix would have shown up by now, and didn't.

Pippin
2008-Sep-24, 05:30 PM
Allright give me a hard time for this one but..
CERN was giving tours of those tunnels immediately prior to switching on, correct? Nice photo ops and press releases? But now they can't work on any repairs for months? Sounds more likely to me that they have to wait for the radioactivity to die down before they can make any repairs.

And my usual humor: In fact CERN did create a mBH, but no worries, it only devoured their operating budget before disappearing!

GOURDHEAD
2008-Sep-24, 06:23 PM
Whew! Another repreive, however short!!

trinitree88
2008-Sep-24, 07:04 PM
Allright give me a hard time for this one but..
CERN was giving tours of those tunnels immediately prior to switching on, correct? Nice photo ops and press releases? But now they can't work on any repairs for months? Sounds more likely to me that they have to wait for the radioactivity to die down before they can make any repairs.

And my usual humor: In fact CERN did create a mBH, but no worries, it only devoured their operating budget before disappearing!

Pippen. As one who has walked accelerator tunnels a number of times, I doubt the short run has left the background at levels unsafe for workers to enter and repair. The beam dump usually accepts the majority of the hits and that's removable.
They're going to need to check each of the magnets out in succession to see that they are each running in acceptable parameters before wholesale operations resume. A team will schedule the repair sequences and safety checks, No black hole materialized or will materialize, or a cosmic ray would've eaten up Mt Everest, top to bottom to infinity and beyond millenia ago...like Buzz Lightyear. Helium is expensive and they'll need to check the plumbing for the cooling coils.
We blew up plenty of rockets in the space race, :shifty:sank ships by the thousands exploring the world, :shifty:not to mention human losses, and if you want to make an omelet, you're going to have to break a few eggs along the way:shifty:. It will be interesting when it runs again. Cheers. pete

megrfl
2008-Sep-24, 07:53 PM
Whew! Another repreive, however short!!

haha. You're not serious, right??

cjameshuff
2008-Sep-24, 08:14 PM
CERN was giving tours of those tunnels immediately prior to switching on, correct? Nice photo ops and press releases? But now they can't work on any repairs for months? Sounds more likely to me that they have to wait for the radioactivity to die down before they can make any repairs.

The problem is simply that some very large pieces of machinery are at a handful of degrees above absolute zero. Before any work can be done on it, they have to get it all warmed up without breaking anything with a sudden rise in temperature, which evidently takes 3-4 weeks itself, and be sure the tunnel's not going to get filled up with ultra-cold helium while people are in there. Then they have to fix the issue and cool the thing from near room temperature back down to a few degrees above absolute zero, again without breaking anything with thermal shock or wasting huge amounts of helium.

They were planning to shut down to perform additional work on it over the winter, with this accident there just won't be time to do useful work before the shutdown. I see absolutely no reason to invent conspiracies to cover up dangerous radioactivity to explain the delay.

Pippin
2008-Sep-24, 08:16 PM
Oi trinitree88,
I went out of my way to put the blackhole comment under my humor section!
As for the radioactivity, they require 48 hours in a controlled dump so I don't think it's unreasonable to "suggest" that in the unforeseen accident which occurred a greater time period would be needed for the background radiation to drop to a safe level. I think I qualified it enough with my "sounds more likely to me". I am of course cynical by nature, but 5 months for it to warm up and cool back down seems a little funny to me. They have nice photo shoots from late august with scientists wearing light jackets and no gloves touring the facility including the fellow with the torque wrench that was made fun of in another post.

Pippin
2008-Sep-24, 08:37 PM
And my usual retraction: After rereading the news articles concerning the recent breakdown it appears that they did not even have the beams on during the accident. So my radiation suggestion seems off base certainly. I'll stick by my humorous observation of them blowing their operational budget on repairs though!

cjameshuff
2008-Sep-24, 08:43 PM
As for the radioactivity, they require 48 hours in a controlled dump so I don't think it's unreasonable to "suggest" that in the unforeseen accident which occurred a greater time period would be needed for the background radiation to drop to a safe level. I think I qualified it enough with my "sounds more likely to me". I am of course cynical by nature, but 5 months for it to warm up and cool back down seems a little funny to me. They have nice photo shoots from late august with scientists wearing light jackets and no gloves touring the facility including the fellow with the torque wrench that was made fun of in another post.

It's not going to take 5 months to do it. The winter shutdown was talked about before the thing was even cooling down for the first run. 3-4 weeks to warm it up, and it's mid-late October. A few more weeks to fix the problem and check everything out so you don't discover something wrong after all the time and expense of cooling it down, and it's November. At that point, they probably wouldn't get it cooled all the way down to working temperature before they had to start warming it up for the winter shutdown. The people wandering around in jackets were not working on faulty wiring buried within the depths of a coil at -170 C!