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In 1954 the European Laboratory for Particle Physics was founded

That is not true as well. The official name is "European Organization for Nuclear Research".

"European Laboratory for Particle Physics" is just a common nickname which serves better.

See, http://public.web.cern.ch/public/en/About/Name-en.html for details.

I read some while ago that the LHC was the first particle accelerator powerful enough to basically destroy itself if the beam was dumped directly into the walls.

The energy stored in the entire beam will be around 350MJ, which, if I did the conversion correctly, is equivalent to about 83kg TNT. Of course it won't be able to dump all of it in an instant (at least not in the same location), but I imagine it could still be quite destructive if it fails.

From what I've heard from the computation / scientific side of CERN, it seems that most of them are using Linux as their main OS. Unfortunately the official distribution (SLC 4) is stone age by now, but most of those I've talked to just use Ubuntu. I don't know of any official statistics on this though. The LHC grid is also AFAIK mainly on Linux.

From what I've heard from the computation / scientific side of CERN, it seems that most of them are using Linux as their main OS. Unfortunately the official distribution (SLC 4) is stone age by now, but most of those I've talked to just use Ubuntu. I don't know of any official statistics on this though. The LHC grid is also AFAIK mainly on Linux.

french police
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Thats 5 minutes of googling (im sure EU offices of google also use linux) if i got paid to do a study, I'm sure i could find more.

It's ironic how this comment derides CERN, while being allowed to do so only thanks to the very technology developed there.
CERN - Where the web was born
http://public.web.cern.ch/Public/en/About/Web-en.html

Because the level of irony created in anyone wearing it would destroy time.

I heard the rumor that wearing it is forbidden within three miles of the Large Hadron Collider.

I've never seen a theoretical description of any transistor device that required any form of quantum mechanics for its explanation.

Maybe not transistors as usually used, but LEDs show quantum mechanics quite directly. Here's a simple lab to measure Planck's constant using LEDs.

Perhaps Somalia will help curb the trend.

These undergradutes are members of the collaboration working under supervision of experienced physicists so they have full access to everything. Anyway consulting the technical design reports will give you some hardware info on CMS but its not really presented in a way accessable to a non physicist.

All this was discussed back in December. The LHC staff had been arguing over whether to go for a quick fix or a major redesign of the magnet protection systems and liquid helium pressure relief valves, and the new CERN director decided to go for the major redesign. Good move. Otherwise this would probably happen again in the years to come.

It's a big fix. Most of the magnets have to be physically moved along the tunnel to the lift shaft, brought to the surface, overhauled, checked out, and returned to position. Then the entire "commissioning" process, which took months, has to be done over.

The original LHC design goal was that a magnet quench would result in a few hours of shutdown, not a year. It became painfully clear that this hadn't been achieved.

The answer you accept depends on whether you want something that does what you want without having to think, or if it allows you to ask the question. CERN has their own version of Scientific Linux, but us proles can't download it. If anybody at CERN would allow me a copy, I would gladly mirror it for the rest of us.

(You can only get a floppy boot image, for a network install AFAICS, and to install on the network, you need a login)

Too specific? I'd say no where near specific enough. I'm an experimental physicist, an experimental particle physicist and we use almost nothing but Open Source software. Mind you that is mainly because things like MatLab, LabView etc. cannot cope with what we need them to do. Hence most of the time we write our own software using Open Source tools and use the Linux OS both for massive clusters as well as embedded processors using in the detector's electronic frontends.

There is one tool, root, that we use for I/O and analysis. It is by far the worst designed and written piece of C++ I have ever had the misfortune to encounter but its I/O is extremely fast and powerful...once you get it to work. I'm not sure I'd recommend it but if you do it is best used via the Python interface which offers a layer of insulation from the full horror of the interpreted pseudo-C++ environment.

The only real exceptions to Open Source I can think of are the CAD software used to design detectors and electronics. Some of the embedded CPUs also used to use propriety OS's but I don't think that this is very common now - at least not on the projects I've had experience with. So perhaps if he explained what sort of experiment physics he was interested in it would help to be able to give advice.

The vast majority of this list are packages in the old, fortran-based CERNLIB. Still around bug in legacy code mode. The modern replacement is Root.

Aimed squarely at high energy experimentalists, and used for data analysis and simulation. In that field, DAQ code is nearly universally highly custom since the electronics it is interfacing with is also custom. Usually built with FOSS tools, though, such as gcc.

The vast majority of this list are packages in the old, fortran-based CERNLIB. Still around bug in legacy code mode. The modern replacement is Root.

Aimed squarely at high energy experimentalists, and used for data analysis and simulation. In that field, DAQ code is nearly universally highly custom since the electronics it is interfacing with is also custom. Usually built with FOSS tools, though, such as gcc.

If you're looking for a high concentration of physicists with a history of openness and demonstrable experience with FOSS, why not try CERN? Didn't Tim Berners-Lee create the World Wide Web in order to facilitate collaboration amongst really large, geographically scattered groups working on high-energy physics projects?

I guess back in the day, they couldn't find any commercial projects that would do the job...

For simple tasks, even with big data sets, I've had good results with qtiplot http://soft.proindependent.com/qtiplot.html. For really complex stuff, there's root from CERN http://root.cern.ch/

Sure. But if you had one of these in space, that would not be an issue. The beam is charged, and that will make it spread out - by my calculations, to maybe a meter wide in 1000 km, which would limit the range.

I think that the beam dump targets are impressive. Down 600 meter tunnels there are 7 meter long graphite dumps, with 750 tons of shielding, just to safely absorb the beam energy when they want to shut the thing off.

I am not so sure. The first package would burn a passage through the atmosphere. The next packages will then travel down that path. That could increase the range. But my gas physics is sketchy, and i don't have access to a high energy particle accelerator to test with. I believe that there will be 156 bunches with an inter-bunch distance of ~8 meters apart (25 ns) once the Death St... LHC is fully operational.

I know the beam dumps contains defocusing magnets to lower the beam intensity. Then they are allowed to drift for ½ a kilometer before hitting a 7m long graphite core.

more info here.
http://lhc-machine-outreach.web.cern.ch/lhc-machine-outreach/components/beam-dump.htm

American scientists are a major contribution to the LHC:

1200 physicists from 90 American universities and laboratories have joined with scientific colleagues from around the world to collaborate in LHC experiments at the horizon of discovery.

reference

I feel like nationalist rivalry aren't part of this equation.

Second CERN is an independant institution. See their directors CERN press release and tell me where is the politician responsible for this blackout.

Here is a picture of a simulated collision in the ATLAS detector that creates a black hole:
http://cdsweb.cern.ch/record/936914

This happen all the time near earth and is not dangerous at all. This is nothing unknown, or mystic or strange. AFAIK the LHC is not even the first accelerator to create black holes.

What needs to be mentioned if such a statement is to be of any use, is how long such melting is expected to take.

According to this CERN page, in the few microseconds that it takes a beam dump to complete. The circulating kinetic energy of the beam is an impressive 350 MJ, equivalent to running a 1000 watt heater for 97 hours.

nope, the damn thing had a giant liquid helium leak... see here.
Perhaps caused by a capacitor, although I doubt it. The article stipulates only an electrical failure between two magnets.

It seems the brightest minds in the WORLD can't build a 17 mile superconducting mechanism that works reliably... How is it that this superconducting power grid is supposed to span hundreds of thousands of miles?

I would urge anyone attempting significant data analysis to try a dedicated analysis software package such as ROOT. ROOT has much more support for data trees, histograms, functions, fitting, etc., and ROOT now also has a Python interface.

Nice summary, unfortunately you come of as a raving lunatic claiming that epicycles IS the only explanation mankind need and that it's BLASPHEMOUS to claim that there is some other kind of explanation!

I still like facts, and thus I'll happily wait for the CLOUD experiment at CERN with regards to Svensmark's hypothesis.

http://physicsworld.com/cws/article/news/3124

http://cloud.web.cern.ch/cloud/

With all the GCC bugs Linux has? With the poor track record on security?

The bugs usually don't affect the ability to compile code effectively. And I'm sure Solaris has just as many security flaws, it just is less audited as it is proprietary software (with the exception of OpenSolaris which has downloadable source code but I'm not sure if it is OSS) and not used as much as Linux, not to mention that every proprietary software company in existence spends money on "studies" to find security flaws in Linux so they can proclaim that *insert OS here* is much more secure and stable than Linux, Solaris has a lower marketshare so it is less targeted by these "studies".

For apps, on Unix, thanks, but no thanks. Not with that sloppy "release early, release often" process. Even the LHC project had security problems due to Linux. Wake up!

Release early, release often usually makes applications more secure and stable in the long run though.

And I'm sure that if the exact same software was running on a Solaris box it would have magically been immune to the attack?

This incident occured at 10:13 on 10th September. Due to an incorrect configuration in a private account on one of the CMS Web servers, it became possible to overwrite a Web page. The issue was detected within a few hours and full CMS operations were always guaranteed. The problem is understood, has been corrected, and as part of the review process started by CMS, the affected service has been terminated. Security issues in Web applications are a common threat, and the CERN Security Team recommends all service managers to review the security of their web applications. More information is available at: http://cern.ch/security/webapps/ The CERN Security Team

According to http://it-support-servicestatus.web.cern.ch/it-support-servicestatus/IncidentArchive/080915-CMSMON.htm it was an idiot admin who misconfigured an account. You mean to tell me that admins don't make mistakes when running Solaris? Wow! I should totally switch over, perhaps I wouldn't ever make a typo or grammatical error either!

With all the GCC bugs Linux has? With the poor track record on security?

The bugs usually don't affect the ability to compile code effectively. And I'm sure Solaris has just as many security flaws, it just is less audited as it is proprietary software (with the exception of OpenSolaris which has downloadable source code but I'm not sure if it is OSS) and not used as much as Linux, not to mention that every proprietary software company in existence spends money on "studies" to find security flaws in Linux so they can proclaim that *insert OS here* is much more secure and stable than Linux, Solaris has a lower marketshare so it is less targeted by these "studies".

For apps, on Unix, thanks, but no thanks. Not with that sloppy "release early, release often" process. Even the LHC project had security problems due to Linux. Wake up!

Release early, release often usually makes applications more secure and stable in the long run though.

And I'm sure that if the exact same software was running on a Solaris box it would have magically been immune to the attack?

This incident occured at 10:13 on 10th September. Due to an incorrect configuration in a private account on one of the CMS Web servers, it became possible to overwrite a Web page. The issue was detected within a few hours and full CMS operations were always guaranteed. The problem is understood, has been corrected, and as part of the review process started by CMS, the affected service has been terminated. Security issues in Web applications are a common threat, and the CERN Security Team recommends all service managers to review the security of their web applications. More information is available at: http://cern.ch/security/webapps/ The CERN Security Team

According to http://it-support-servicestatus.web.cern.ch/it-support-servicestatus/IncidentArchive/080915-CMSMON.htm it was an idiot admin who misconfigured an account. You mean to tell me that admins don't make mistakes when running Solaris? Wow! I should totally switch over, perhaps I wouldn't ever make a typo or grammatical error either!

It is - the issue is that the thing is just so huge! (and, you can't run it without all sections operational).

If you look here, you can see that sector 3-4 is warm.. that's the compartment that was affected. Detailed graphs are available here.

It is - the issue is that the thing is just so huge! (and, you can't run it without all sections operational).

If you look here, you can see that sector 3-4 is warm.. that's the compartment that was affected. Detailed graphs are available here.

Look at the LHC cyro status for sector 3-4. Average magnet temperature is now at 70K, and slowly creeping up to room temperature. Notice the expanded vertical scale on the graph. Compare with the other sectors, holding with liquid helium at 1.9K.

Warmup is slow. Cooldown is slower. Several kilometers of pipe and a hundred or so magnets are involved.

It's not that bad, though. It looks like they won't have to take magnets out of the tunnel for rewinding. That's a huge job. This is just a slow one.

They can warm up or chill down sector 3-4 during the shutdown period. The rest of the system would normally be cooled during shutdown anyway.

What failed, apparently, was a non-cryogenic high-current electrical connection in one of the magnets. They didn't have a magnet winding failure, which is much worse; the whole magnet would probably have to be removed from the tunnel for repairs if that happened. To fix the current problem, they're going to have to bring some magnets up to room temperature, lose vacuum, fix the thing, and chill everything down again. It's a slow process, but not too bad.

Even though the statements from CERN are relatively terse, you can watch the LHC cyro status on line, which gives a good idea of what's being worked on.

I think it should be noted that "sector 34" is not the 34th out of some large number, it's "the sector between points 3 and 4", which is an entire eighth of the assembly.

http://hcc.web.cern.ch/hcc/cryo_main/cryo_maintain.php

A) This isn't just some ordinary big, complicated machine. That should be obvious. For example, there was a huge hurrah when it launched.

Sure. Nevertheless, problems occur at accelerators all the time. Maybe it's a bit of a new situation for physicists that the general media is interested whether this particular accelerator is online or has technical problems.

But it was clear right from the start that it will take weeks until they get first collissions, that there will be set backs and problems. It will probably take the experiments a year or longer to understand the data from their detectors. I'm sure there never was the intention to make a press release for every problem on the way to first results.

B) It has been down longer than it was up. By a factor of what, 3?

Big deal. I mean, they just started last week. And especially at the beginning you expect problems with such a complicated machine. There is a reason why first collisions are only expected after a while of testing (and fixing problems).

C) Isn't this the controversial machine that may or may not destroy the planet itself? Doesn't that kind of debate set the stage for transparency?

The status of the machine is available online for everybody. Cryo status is here:
http://hcc.web.cern.ch/hcc/cryo_main/cryo_maintain.php

It does not get much more transparent than that. I guess that CERN just is not used to make a press release for every problem.

D) THOUSANDS have contributed BILLIONS from across the globe. The damn thing better be worth it, and when it breaks it damn well better be fixed pronto. Otherwise, 'what a colossal waste', right?

Yes, but nobody who contributed expected that you flip a switch and everything just works. These people who contributed are experts and know that there is quite some work ahead.

BTW, in the US there is the Relativistic Heavy Ion collider (RHIC).
http://en.wikipedia.org/wiki/RHIC

It cost more than 600 Million Dollars to build and just runs a few months (I think 2-3) a year (among other things due to energy constraints on Long Island in the summer). In 2006 it almost did not run at all, due to budget cuts. They did take data that year eventually because a private company chipped in 13 Million Dollars.

The current status of the beam can always be viewed here

Which currently says "We just had a major quench in sector 34. More news as we get it"

IIRC a quench (loss of superconductivity because of the magnetic fields) is likely to cause extra damage, so this sounds a lot more important than a simple transformer failure. Plus therer might be design issues that caused it.

Good luck to the LHC team. I guess this is how a real beta goes

The webcam is a great source of information on CMS :), but if you want to know the status of the LHC, check the following links:
The current status of the beam can always be viewed here
All other status informations are linked from here
So maybe they didn't make a press release, but perhaps journalists should be smart enough to find these pages instead of claiming conspiracies?

The webcam is a great source of information on CMS :), but if you want to know the status of the LHC, check the following links:
The current status of the beam can always be viewed here
All other status informations are linked from here
So maybe they didn't make a press release, but perhaps journalists should be smart enough to find these pages instead of claiming conspiracies?

They have day-to-day log of the activities at https://lhc-commissioning.web.cern.ch/lhc-commissioning/dailynews/index.htm I didn't have any problems finding this logs at the LHC website.

Transformer outage and cryogenics breakdown is logged on September 13. They were not 'rumors'.

From the site's page on computing: The Large Hadron Collider will produce roughly 15 petabytes (15 million gigabytes) of data annually - enough to fill more than 1.7 million dual-layer DVDs a year!

Those sneakers might need to be replaced pretty quick...

I know you are being funny, but CERN uses Scientific Linux. [scientificlinux.org]

SL is a Linux release put together by Fermilab, CERN, and various other labs and universities around the world. Its primary purpose is to reduce duplicated effort of the labs, and to have a common install base for the various experimenters.

I know you are being funny, but CERN uses Scientific Linux.

SL is a Linux release put together by Fermilab, CERN, and various other labs and universities around the world. Its primary purpose is to reduce duplicated effort of the labs, and to have a common install base for the various experimenters.

It's called "the grid". just do a google search for "LHC grid" and you'll get lots of info. Here's a couple of links for starers:
http://lcg.web.cern.ch/LCG/
http://www.gridpp.ac.uk/cernlcg.html

The BBC has a less tchnical piece on te grid: http://news.bbc.co.uk/1/hi/sci/tech/7534866.stm

http://lhcathome.cern.ch/

For one thing (leaving the whole "begging the question" mistake aside), to send absolutely mind-bogglingly large amounts of data to the Grid. The bandwidth required is massive, and they use a combination of private, dedicated links and regular Internet connections to do it.
(Read up on the LHC Grid; it's fascinating stuff!)

How about LHC@home? :)

Just a reminder, the scientists at CERN needed a good way to share information, and the Web was the result.

http://public.web.cern.ch/Public/en/About/Web-en.html

Who knows what spin-offs might come from the LHC?

Maybe we should call it the wine-cellar effect. At any rate, I find it surprising that they're only using one storage system, and only "many" terabytes after considering it creates 15PB per year, unless "terrabytes" are a newly named unit of measure.

http://cmsdoc.cern.ch/cms/performance/FirstBeam/pictures/scr-celeb1.jpg

there is a girl in the picture!
in a scientific facility

am pretty sure is computer generated image or...

a group of scientist went back in time and transform science in something cool that girls like to hang out around!!!

I've heard somewhere that it was linked to earth tides . Wikipedia's references here and here (pdf). They apparently modify the geometry of the ring slightly..