LHC@home

he Large Hadron Collider near Geneva will be out of action for at least two months, the European Organization for Nuclear Research (Cern) says.

Part of the giant physics experiment was turned off for the weekend while engineers probed a magnet failure.

But a Cern spokesman said damage to the £3.6bn ($6.6bn) particle accelerator was worse than anticipated.

The LHC is built to smash protons together at huge speeds, recreating conditions moments after the Big Bang.

Scientists hope it will shed light on fundamental questions in physics.

On Friday, a failure, known as a quench, caused around 100 of the LHC\'s super-cooled magnets to heat up by as much as 100C.

The fire brigade were called out after a tonne of liquid helium leaked into the tunnel at Cern, near Geneva.

Cern spokesman James Gillies said on Saturday that the sector that was damaged would have to be warmed up well above absolute zero so that repairs could be made.

While he said there was never any danger to the public, Mr Gillies admitted that the breakdown would be costly.

He said: \"A full investigation is still under way but the most likely cause seems to be a faulty electrical connection between two of the magnets which probably melted, leading to a mechanical failure.

\"We\'re investigating and we can\'t really say more than that now.

\"But we do know that we will have to warm the machine up, make the repair, cool it down, and that\'s what brings you to two months of downtime for the LHC.\"

Source: BBC News

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www.chris-kent.co.uk aka Chief.com

Oops!

Shoot! I was wondering where I had left that spanner!

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Today I got a big chunk, it is making a million turns, about ready to finish up, and had a big smile on my face for at least doing something now on the project.

Then I read the message board, and it felt like my heart popped out of my chest. What terrible news. Two months will seem like a life time to me.

Well it happens, and expected to happen as Early Life Failures come out. Time just caught up. I send my \\\\\\\"hang in there\\\\\\\" to all the support teams, crunchers, and especially to the researchers. I can assume there are more disappointments than I have. I will be wishing you all well, hopefully a simple fix and a good cool down again.

Forgive my earlier frivolous post, I was just trying to lighten the mood in what is a desperately disappointing situation.
Thankfully due to CERN\'s superb safety procedures no-one was hurt, nor was there ever any danger of anyone being hurt.
Here\'s to a speed fix!

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BUMMER.....hope they get things patched up as soon as possible

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Time is God's way of keeping all things from happening at once. - Anonymous

Large Hadron Rap
LHC Images

Muhahahaha !
Finally Mr Tibbles !
All my evil planning is coming to a success - Wahaha

Oh wait !
Is this the diabolic world dominating engineer cult of the blackhole doom smasher conspiracy support group ?
Opps, sorry - Wrong forum.

Hope the problem and its fix isnt a biggie.
Ta Ta

Kitty-Crunchies for Mr Tibbles ?

http://sciences.blogs.liberation.fr/home/2008/09/coup-dur-pour-l.html

http://tempsreel.nouvelobs.com/actualites/sciences/technologies/20080922.OBS2192/le_lhc_a_larret.html?idfx=RSS_sciences

:) i am french.

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The Large Hadron Collider near Geneva will be out of action for at least two months, the European Organization for Nuclear Research (Cern) says.

Well hopefully that will free up some scientists to fix the Sixtrack issue with BOINC 6.2 clients, and to finish debugging Garfield.

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... a tonne of liquid helium leaked into the tunnel ...

Does that mean everyone is now speaking in high pitched Mickey Mouse voices?

Mike

... a tonne of liquid helium leaked into the tunnel ...

Does that mean everyone is now speaking in high pitched Mickey Mouse voices?

Mike

Could be worse! a little anti-helium and everyone starts sounding like the late-great Barry White.

The whole apparatus works under extreme conditions. I\'ve read that the 3 m long magnets get shortened by 20 cm when supercooled. Imagine the mechanical problems. I think that a failure was almost inevitable. Luckily no one was hurt, people die every day in work accidents under normal conditions.
Tullio

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No new stuff at the LHC until after the winter shut-down.

Here\'s hoping 2009 brings better fortunes for the team.

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www.chris-kent.co.uk aka Chief.com

The whole apparatus works under extreme conditions. I\\\'ve read that the 3 m long magnets get shortened by 20 cm when supercooled. Imagine the mechanical problems. I think that a failure was almost inevitable. Luckily no one was hurt, people die every day in work accidents under normal conditions.
Tullio

At my work, railroad, we are taking in account that a 100 meter long steel or concert construction will change 1 mm in length for every 1 degree Celsius change of the temperature.

That means that a 3 meter long steel rail cooled down to -250 Celsius would shrink 250x3\100 = 7.5 mm. How come that these magnets shrinks so much as 200 mm?

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That means that a 3 meter long steel rail cooled down to -250 Celsius would shrink 250x3\\100 = 7.5 mm. How come that these magnets shrinks so much as 200 mm?

Well the magnets are not made of steel used for building rails. They are made of different materials like maybe Alnico & a combination of many other alloys - each having their own expansion coefficinets, so you see the difference.

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Time is God's way of keeping all things from happening at once. - Anonymous

Large Hadron Rap
LHC Images

That means that a 3 meter long steel rail cooled down to -250 Celsius would shrink 250x3\\\\100 = 7.5 mm. How come that these magnets shrinks so much as 200 mm?

Well the magnets are not made of steel used for building rails. They are made of different materials like maybe Alnico & a combination of many other alloys - each having their own expansion coefficinets, so you see the difference.

I just did not realized that the difference between different metal was that big.

Which metal has the biggest temperature dependent change?

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Based on this page http://www.engineeringtoolbox.com/thermal-expansion-pipes-d_283.html which is linked to from the page you linked to Dagorat it seams that the coefficients gets bigger when the temperature goes higher

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The whole apparatus works under extreme conditions. I\\\\\\\'ve read that the 3 m long magnets get shortened by 20 cm when supercooled. Imagine the mechanical problems. I think that a failure was almost inevitable. Luckily no one was hurt, people die every day in work accidents under normal conditions.
Tullio

At my work, railroad, we are taking in account that a 100 meter long steel or concert construction will change 1 mm in length for every 1 degree Celsius change of the temperature.

That means that a 3 meter long steel rail cooled down to -250 Celsius would shrink 250x3\\100 = 7.5 mm. How come that these magnets shrinks so much as 200 mm?

Probably my mistake. Dipole magnets, used to curve the beam, are 15 m long and quadrupole magnets, used to focus it are 5 to 7 m long. I don\'t know what they are made of but they are evidently longer than 3 m, Sorry.
Tullio
Nature Magazine writes that a faulty weld between two conductors
provoked a short which caused a small explosion sending a piece of metal to perforate a tube carrying liquid helium.