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From the other end of the telescope - would what is essentially an imaging detector like a bubble chamber be suited to a high-data rate situation like the LHC?

I wish physicists would stop using the word "measurement" when talking about quantum mechanics....We don't get to keep the original particle after we're done.

Actually that is not true if you go to high enough energy: have a look at this. Those four tracks coming out of the centre of the ATLAS detector at the LHC are muons, a heavy cousin of the electron. The muons are neither stopped nor destroyed by the detector but they do lose a little of their energy as they pass through it but for high energy particles this really is a very small, non-instrusive fraction of their energy. We can even use the curvature of the track in ATLAS' magnetic fields to measure the momentum of the particle.

Even if you stay at low energies there are biophysicists who can use lasers to pull apart single DNA and other organic molecules in non-destructive ways to study how they fold which involves quantum transitions between different folding states. So there are plenty of non-destructive QM based measurements which we can do both on fundamental, and non-fundamental particles.

If your objection is that we have 'changed' the system by making the measurement then perhaps it is worth reflecting that, at a fundamental level, everything is quantum mechanical. Hence there is no measurement that you can make which will not involve changing the system you are measuring. So if your criterion is that your measurement must not change the system you have just ruled out any measurement which any scientist has ever made.

They have strong indications that the particle is spin-0.
In the plot, blue is the expected data for spin-0, red for spin-2. The black line is derived from measurements and nicely corresponds with the peak of spin-0.
See also here.

One chance in three million :-)

Here is what Atlas found for the confidence level at various energies. The spike at 126.5 GeV breaks out to 5 sigma.

But everyone that thinks otherwise is welcome to calculate sqrt(1 - v^2/c^2) for their experiment's velocity and see if the values vary significantly

I'm not sure that works too well - my experiment is large and very stationary but the particles we collide in the middle have a gamma [which is 1/sqrt(1 - v^2/c^2)] of well over 3,500.

Can't explain something, Dark Matter is the reason! Can't find a cause, Dark Matter is it!

This is completely incorrect. This work is the result of looking for Dark Matter. Dark Matter is the best explanation for galactic rotation curves and the cosmic microwave background. Depending on what the Dark Matter is it may annihilate with itself and produce, amongst other things, electron-positron pairs. In fact the paper is really a very beautiful and elegant bit of work since the first bit of evidence which lead to this comes from the background 'noise' of one of the major pieces of evidence for Dark Matter - the WMAP data! As such, far from noticing something and then attributing it to Dark Matter, this is actively looking for something that suggests evidence for Dark Matter. True the evidence does not show that it HAS to be Dark Matter but if you cannot attribute it to anything else which is known and you have models which suggest that Dark Matter might produce such a signal it is very interesting.

Arkani-Hamed et al have a model which may explain this and which, if correct, predicts jets of leptons (electrons or muons) at the LHC. This is actually one of the things which my colleagues and I are looking for on the ATLAS Experiment. If we do observe them then this will be further evidence for Dark Matter and not a "oh, something else we cannot explain and put down to Dark Matter". Until we have enough bits of evidence that, combined, show that Dark Matter is the only possible cause there will always be some doubt but that should not be construed as flailing around and using Dark Matter to explain every observation that is inexplicable. Indeed, the fact that we are using Dark Matter models to suggest observations and experiments to perform and then finding that these return "inexplicable" results is very, very interesting!

No-one is stopping you analyzing the data and getting a Nobel for finding a new particle. Wherever you are. The ATLAS data for one is being sent all around the planet for analysis as there is too much for CERN to analyze. http://atlas.ch/

If you are looking for a picture of a Higgs try this one which shows a Higgs at ATLAS.

Here are a few things that have helped me out:

• The big one: go to LISA. It can be tough convincing the boss to send their one-and-only IT guy, but it's an incredibly exciting environment. You'll learn lots, you'll meet lots, and you'll get to rub shoulders with people doing incredible things -- and people in the same boat you are.
• If you can't go to LISA, start reading their proceedings. They've just opened up everything to the public (previously you had to wait a year if you weren't a member), and there are some incredible gems to be found. The MP3s from LISA '07 weren't as good as being there would have been (sob), but they're still damned good.
• You should still get a membership in SAGE. Subscribe to the mailing lists, get a subscription to ;login:, and inhale deeply.
• Look around for professional organizations to join, or other opportunities. There's a sysadmin group at the university where I work; there's also a committee trying to figure out what the university's IT strategy should be for the next 5-10 years. I've been lucky enough to be involved with both, and they're interesting. Sure, I run a small shop, but I've rubbed shoulders with (well, envied from across the room :-) the guy in charge of a cluster of computers that'll be processing data for the ATLAS experiment.
• Start your own techy/sysadmin conference, a la LUGRadio Live. No, LUGRadio Live isn't particularly sysadmin-oriented, but I have the strong impression that the organizers just decided they wanted to hold their own conference, and they did. And if you look at the schedule for their US conference, it's got a damned impressive list of presenters. (I'm considering starting a sysadmin conference next summer in Vancouver, BC...anyone interested?)
• Other sources of info: Planet Sysadmin (disclaimer: they've got my blog in there), ONLamp, and your local LUG.

Hope this helps!

Take a look at the
It is the layer of the ATLAS detector that is closest to the interaction point where collisions happen. The first layer (cylinderical) only 5 cm away.
As for the radioactivity being "potentially dangerous" -- well, I would not want to ingest any of it or sleep next to it, if that's what you mean... But actually no, we will be able to take the detector out and replace it if needed. Remember that exposure is what counts and that depends on distance, as well as how long you have been exposed to it. So in this case, the answer is that given what we have to do with it, it is not dangerous.

American physicists dont care if a discovery comes from Fermilab or from CERN, because many of them work at both, or at least have colleagues who work overseas from wherever they are. As a US student who used to work at CERN (namely on ATLAS) my research advisors were splitting their time between Fermilab and CERN. NSF and DOE funding are going to both labs, and scientists will be happy just to get some real data to work with.

This week is "the Trigger and Physics week" for ATLAS, which is one of the two major experiments at the LHC. The opening talk by the head of the collaboration clearly laid out the LHC schedule, but on slides that are not published on the agenda. The original article that is referred in the /. gist has gotten it wrong!

The LHC schedule can not be publicly released until it is approved by the CERN council, which is meeting on the 18th of June. Presumably, once approved, CERN will make a public statement about the plans.

Currently, the plan is to close the experiments for "bake-out" and readying towards a full LHC cool-down and vacuum test around end of March. "Closing the experiments" means that the beam-pipe is one sealed throughout the 27km ring, which seriously limits the movement, fixing and other assembly tasks of the detector communities, so this is a "deadline" for detectors to be "ready for data-taking".

It takes anywhere between a month or two to ready the ring for insertion of *a* beam. It is looking likely right now, that *a* beam will be inserted into the ring around mid-May. However, that is not enough for the operation of the LHC. The LHC is a Collider, so it needs *two* beams to collide. Colliding two beams within an average design beam spot of 16 microns, is no easy task after having them traveling around 27km. (Before the beams are steered the collide, they are "squeezed" to a smaller radius so that the "density" of collisions are higher. This density of collisions, is what determines the luminosity, or, the number of interactions that happen between two beams, and gives the effective high resolution power of the collider.)

Once "one" beam is commissioned inside the LHC, the other beam, traveling opposite to the first one, will be commissioned. Noone really knows how long it will take to really understand and fine-tune the path (or orbit) of the beams inside the ring, but that is what determines when the LHC will get collisions and the first real data will start flowing, if the detectors, can actually time-in and calibrate, and move/push the data off of the detectors into the Grid for analysis. Now, Lyn Evans, who is the head of the LHC commissioning has repeatedly said that he imagines that is will take at least 3 months to get collisions, once a single-beam is commissioned..

So FALL 2008 is the earliest any realist is expecting to see collisions from the LHC. Then the ball is in the detectors' courtyard to collect data continuously and efficiently, to be able to calibrate all detectors in a timely fashion, to identify and fix detectors problems, and to push the (high bandwidth) data out to the analysis farms...

First physic results out of the LHC will not be before Summer 2009... The first paper will be a boring "foo is the multiplicity of events" and the next will be "bar is the cross-section for Drell-Yan/mininum bias processes" paper. The one after that might be interesting though!!

Yeah. That's called ATLAS. Except it has a toroid as well as a solenoid technically...

atlas url http://atlas.ch/

http://atlas.ch/webcams.html With images from when they began.

I've been to CERN twice, spending a combined month or so there with my research. Most of the second time I was underground as we were installing my university's hardware contribution into the ATLAS Cavern. It's still very much considered a construction zone, so hard hats and steel toe shoes are mandatory, even when you're just in the electronics rooms. It's fun seeing all the old PhDs running around looking like construction foremen.

Anyway, what I liked most about the film was highlighting the importance of the cafeteria. Although most of the collaboration is done either by email or occasionally webcam, I think the biggest decisions are made with a beer in hand, enjoying the weather, and either staring off towards Mont Blanc (which most of the time is too hazy to discern, but when it's clear, it's beautiful), or watching the nightly game of football (soccer). The beer may not be important for all decisions- the mini bottles of wine could probably work just as well.

What I didn't like in the film was when in the LHC tunnel, the one guy was talking about collisions, mentions ATLAS, and then immediately after they started showing shots of the CMS detector. There is a great but friendly competition between the ATLAS and CMS groups. Building 40 (which houses the ATLAS and CMS offices), basically pits the two opposite one another. When you walk in the central hub, everything to your left is CMS, and everything to the right is ATLAS. The small cafe in the center is the only spot not claimed by either group. Even then, once getting anything from the cafe, CMS people take their food to the tables on their half of the building, and ATLAS to their own side. So although the average person may say it's nothing, I think a lot of ATLAS people would roll their eyes when seeing the movie, thinking that people watching it would mistake the CMS for ATLAS.

Finally, another movie (which won awards!) that starts off giving an overview of ATLAS and the LHC, but then goes back and gives a brief history of 400 some years of scientific experimentation is available here - http://www.atlas.ch/movie.html. Enjoy.

I did my experimental particle physics PhD on an experiment named BaBar, you know, like the elephant. Are you telling me that isn't public-friendly?

A similar experiment based in Japan is called Belle and one in upstate NY called CLEO. One of the other experiments at the LHC is called ATLAS. They all seem reasonably public-friendly names (but then I am one of the folks you are saying don't know what a public-freindly name is, so I suppose my views are irrelevant).

As to the PR, it's pretty hard to make particle physics accessible to other physicists, let alone the general public. The essence of the question that BaBar and Belle were trying to answer is "Is CP violated in strong interactions?". It generally takes several years of university physics just to understand the question. The most "successful" PR projects never even seem to get to the crux of the project.

Incidentally, the answer is "yes, maximally". Your tax dollars at work!