LHC News

tullio
tullio
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You mean that us not

You mean that us not believers cannot approach God's particle? This reminds me of HAL 9000 sabotaging the mission in A Space Odyssey.
Tullio

Bikeman (Heinz-Bernd Eggenstein)
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Also a good explanation :-) .

Also a good explanation :-) . Maybe in a distant parallel universe, someone just got sent to a mental institution for claiming that right in front of him a wormhole opened and his baguette just vanished into it, probably re-appearing in another world... who knows.

Anyway I'm happy no real damage was done, but you can't help but being worried that the awesome complexity of this machine might turn out to be nightmare in terms of MTBF and MTTR (or duty cycle, if you will).

Bikeman

Rod
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Reading papers like this now,

Reading papers like this now, just cause a buzzing in my head so I just turn to end and look at the conclusions.

5.4. Reliability
In LEP, the mean time between failure (MTBF) for power converters is slightly less than 100k hours. LHC will have nearly twice as many power converters as LEP, so for a similar failure rate, the MTBF will need to be doubled. With 1700 systems, an MTBF of 200k hours will mean between one and two failures per week. To achieve even 200k hour MTBF will not be trivial, so strategies to cope with converter failures will be needed.
This is especially true for the orbit correctors. These converters account for half the total number and will be installed in the tunnel where radiation will be a serious issue. It will be very important for the orbit correction system as a whole to be tolerant of corrector failures.

Scary:-) They should have built two or maybe thirty based on the Mean tine to Repair and acceptable down time :-)

Edit: But it is possible if you got the finances and Military Size Budget and Scary opponent :-)
Its important you have a scary opponent..

Sage Computer

There are some who can live without wild things and some who cannot. - Aldo Leopold

Mike Hewson
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RE: Reading papers like

Message 95023 in response to message 95022

Quote:

Reading papers like this now, just cause a buzzing in my head so I just turn to end and look at the conclusions.

5.4. Reliability
In LEP, the mean time between failure (MTBF) for power converters is slightly less than 100k hours. LHC will have nearly twice as many power converters as LEP, so for a similar failure rate, the MTBF will need to be doubled. With 1700 systems, an MTBF of 200k hours will mean between one and two failures per week. To achieve even 200k hour MTBF will not be trivial, so strategies to cope with converter failures will be needed.
This is especially true for the orbit correctors. These converters account for half the total number and will be installed in the tunnel where radiation will be a serious issue. It will be very important for the orbit correction system as a whole to be tolerant of corrector failures.

Scary:-) They should have built two or maybe thirty based on the Mean tine to Repair and acceptable down time :-)

Edit: But it is possible if you got the finances and Military Size Budget and Scary opponent :-)
Its important you have a scary opponent..

Sage Computer


I like this tactic especially :
"There were usually several hundred tube failures each day, replaced by workers racing up and down the tube racks with shopping carts full of replacements. Automated tests run by the computer itself would cycle the voltage to the tube racks down and back up to induce marginal tubes to fail early, so that the computer would normally run correctly for the rest of the day. Without this process, the MTBF would have been a few minutes"

This is great! Now we have some big numbers to work with. We have to work out exactly how finitely improbable the baguette incident was. Then we take that number and key it into the Improbability Drive, so the Heart of Gold can activate .... :-)

You're right. Ambition, complexity and cost are an unstable mix. Needs glue. In this context paranoia works very nicely thank you. And we're never short of it.

Cheers, Mike.

I have made this letter longer than usual because I lack the time to make it shorter. Blaise Pascal

Rod
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The LHC is nothing but a

The LHC is nothing but a physics experiment. Nothing else.

If it runs for 30 seconds in ten years it has paid for itself.
If it does not run for 30 seconds in ten years it has paid for itself.

There are some who can live without wild things and some who cannot. - Aldo Leopold

tullio
tullio
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No, we paid for it. Tullio

No, we paid for it.
Tullio

Rod
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RE: No, we paid for

Message 95026 in response to message 95025

Quote:
No, we paid for it.
Tullio

You got some return on your investment already.

Italy and the LHC

Edit: But Italy invested heavily for their size of economy especially when they borrowed the investment yikes!!. Canada another G7 country threw in 40 million. But it was better spent than building an aircraft carrier..:-)

Edit: This type of money is better spent on infrastructure but where is the glamour in that :-)

I see where you are coming from Tuillo. I would be pissed off to

There are some who can live without wild things and some who cannot. - Aldo Leopold

tullio
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INFN is also financing the

INFN is also financing the Virgo interferometer at Cascina, Pisa. For many years INFN has devoted itself to nuclear and subnuclear physics, then changed its course and I credit this to Edoardo Amaldi, who is one of the founding fathers of CERN. Among the INFN projects are the ADA and ADONE storage rings in Frascati and also a Tokamak. INFN has got most of the financial support in physics, while other branches, like solid state physics, were barely surviving, The also designed a microprocessor to process physics data, APE, but they were unable to develop a real computer from it and it does not appear in the top 500 list. But hats off to INFN, they continued on the tradition of excellence initiated by Fermi.
Tullio

MAGIC Quantum Mechanic
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adrianxw
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All good things run out of

All good things run out of usefulness I suppose. I read about this gadget in it's early days when I was at school. I was struck by todays pictures of how "compact" it is/was.

At least it is being replaced by something useful, rather than another "admin block" or car park.

Bevatron.

I wonder why it took so long from decommisioning to destruction.

Wave upon wave of demented avengers march cheerfully out of obscurity into the dream.

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