Message boards : LHC@home Science : LHC magnet is being repaired, no collisions for at least several weeks
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Sesson

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Message 48303 - Posted: 22 Jul 2023, 17:24:29 UTC

https://home.cern/news/news/accelerators/accelerator-report-quench-lhc-inner-triplet-magnet-causes-small-leak-major

At 1.00 a.m. + 17 seconds on Monday, 17 July, the LHC beams were dumped after only 9 minutes in collision due to a radiofrequency interlock caused by an electrical perturbation. Approximately 300 milliseconds after the beams were cleanly dumped, several superconducting magnets around the LHC quenched – i.e. they lost their superconducting state.
...
Unfortunately, in the case of the inner triplet magnet located to the left of Point 8, a small leak has appeared between the cryogenic circuit, which contains the liquid helium, and the insulation vacuum that separates the cold magnet from the warm outer vessel, known as the cryostat. This vacuum barrier is crucial for preventing heat transfer from the surrounding LHC tunnel to the interior of the cryostat (this is similar to the functioning of a thermos flask). As a result of the leak, this insulation was lost: the insulation vacuum filled with helium gas, cooling down the cryostat and causing condensation to form and freeze on the outside.
...
it is clear that an intervention with the inner triplet magnet at room temperature will be required. This incident will probably have a great impact on the LHC schedule, with machine operation unlikely to resume for at least several weeks.

Looks like LHC has an MTBF of several days. The power of LHC is too large for a UPS. Time to have a summer break in the extremely hot days!
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[VENETO] boboviz
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Message 48317 - Posted: 26 Jul 2023, 7:31:11 UTC - in response to Message 48303.  

From LHC Twitter account

Leak on IT.L8 localized. Repair ongoing.
Next morning meeting Wed 26/07 @ 9am
No beam until further notice (weeks)
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Philip Nicholson

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Message 48319 - Posted: 26 Jul 2023, 19:27:17 UTC - in response to Message 48317.  

So how does this effect work units?
I have received nothing for days.
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Philip Nicholson

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Message 48320 - Posted: 26 Jul 2023, 19:27:17 UTC - in response to Message 48317.  
Last modified: 26 Jul 2023, 19:27:41 UTC

So how does this effect work units?
I have received nothing for days.
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Harri Liljeroos
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Message 48321 - Posted: 26 Jul 2023, 21:18:38 UTC - in response to Message 48320.  

So how does this effect work units?
I have received nothing for days.

It doesn't. We are calculating just simulations. The dry spell is down to something else (Theory and CMS are currently having tasks to crunch).
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mikey
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Message 48324 - Posted: 27 Jul 2023, 14:14:51 UTC - in response to Message 48319.  

So how does this effect work units?
I have received nothing for days.


It could have to do with you not returning any valid tasks out of the 192 you have gotten, some projects cut people off if they don't return a valid task once in awhile. You might ask someone to take a look at your tasks that knows how to read the error messages and help figure out what your problem is.
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maeax

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Message 48325 - Posted: 27 Jul 2023, 15:00:25 UTC - in response to Message 48319.  
Last modified: 27 Jul 2023, 15:02:28 UTC

So how does this effect work units?
I have received nothing for days.

Do you have yellow triangle's in the Virtualboxmanager for your .vdi?
This vm_image.vdi must be deleted.

btw: this messages are no Science messages.
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[VENETO] boboviz
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Message 48439 - Posted: 13 Aug 2023, 14:41:41 UTC

LHC leak repair: a short photostory
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[VENETO] boboviz
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Message 48471 - Posted: 23 Aug 2023, 15:16:53 UTC

From vistars:
S78 cooldown completed
Beam expected middle of the next week
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[VENETO] boboviz
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Message 48477 - Posted: 30 Aug 2023, 11:55:57 UTC - in response to Message 48471.  

Beam expected middle of the next week


Proton Physics: Setup
Beam jniection expected in about 1hr
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Message boards : LHC@home Science : LHC magnet is being repaired, no collisions for at least several weeks


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