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LHC Success!
Tomahawk writes "It worked! The LHC was turned on this morning and has been shown to have worked. Engineers cheered as the proton particles completed their first circuit of the underground ring which houses the Large Hadron Collider (LHC).
(And we're all still alive, too!)" Here is a picture from the control room which I'm sure makes sense to someone that isn't me.
I thought that the critics of this project were worried about the effects of COLLIDING the particles. Since that hasn't happened yet, this story is a whole lotta nuthin'.
Attention all planets of the Solar Federation! We have assumed control! - Neil Peart
If I'm correct, no collisions have taken place yet.
Correct. That will happen later this month.
Full Tilt
That picture is from smashing the beam into the collimator, not from passing the beam through ATLAS.
This is one of the final tests that you perform before passing the beam through - the result though is that millions of muons from the beam smash and deflect off the collimator, touching off all the different parts of the detectors. That's why you see so many energy deposits (green) throughout ATLAS.
When you're just circulating beams, the only thing you see are Cosmics and BeamHalo - any muons which collide with remaining gas particles upstream of the detector and basically circle right outside of the beam. Here's some pictures of CMS beam halo:
http://cmsdoc.cern.ch/cms/performance/FirstBeam/cms-e-commentary.htm
Those who say the tiny lack holes would dissapear instantly, you are misinformed. They are solid mass. They can only grow, and anything that interacts with them will be sucked in
Mr. Hawking disagrees with you.
And even if he is wrong, my understanding is that particle collisions with the same energy levels happen on a routine basis as cosmic rays strike our atmosphere. That would seem to suggest that either these collisions lack the power to create black holes or Hawking's theory is correct and they evaporate pretty quickly.
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
Here is a picture from the control room which I'm sure makes sense to someone that isn't me.
The image is produced by an event display program, which provides a nice visual representation of the output of the whole detector (ATLAS in this case) for one event. One event here means one beam crossing, generally, which could include up to several proton-proton collisions, but generally only one interesting one.
Now, I'm not completely familiar with ATLAS (I'm a CDF guy), but I'm pretty sure the top left section is the muon chambers. These record, well, muons, which are the only thing which interacts poorly enough to consistently punch all the way through the detector and the layers of steel in front of the muon chambers, but strongly enough to be recorded all the way along its passage.
The top center shows a zoomed in view of the middle of the top left: the calorimeters. Calorimeters record the amount of energy that enters them, and are arranged radially, so that you can see just how much energy (in the form of both mass and kinetic energy) was carried away from the collision in a particular direction. This is accomplished by means of scintillator crystals, which tend to get ionized by the passage of high energy particles, thus absorbing some energy from the particles, and then they reemit that energy as photons, which are collected and measured in photomultiplier tubes. The calorimeters are used to look for most particles, particularly electrons and "jets" (which are a spray of particles resulting from the ejection of a quark from the collision), both of which leave clusters of energy over a significant area of the calorimeter.
The top right is again a zoomed in view of the middle of the top center: the tracking chambers. These act sort of like thousands and thousands of geiger counters; every time a charged particle passes through the vicinity of a wire in the tracking chamber, it records a hit. You can then piece all these hits together in a line to measure the track of a particle. The offcenter pink and blue line is almost certainly a cosmic ray, which will naturally leave a track in the chamber, but not appear to originate from the interaction point. In the lower left, you can see what is probably two different short track segments.
The first three images have been more or less slices out of the center of the detector, perpendicular to the beam line. The lower left is a side-on view, showing the somewhat less important parts of the detector that lie at small angles to the beam line, the so-called forward detectors.
The lower right is probably intended to be a flat plot of the calorimeter, as if you sliced it parallel to the beam line and unrolled it. The height of the bars would then indicate how much energy was deposited in each section. However, at the moment, that plot looks like it is having some sort of overflow problems.
SIGSEGV caught, terminating
wait... not that kind of sig.
I would also like to point out they have to align the particle streams yet, AND this will take some time before they turn the energy levels up on the device to maximum, which as many have pointed out, is the "new territory" area.
Not until the device is at full power and doing collisions is there really any concern.
I suspect full power, "universe shattering" tests won't take place until sometime in December at the earliest.
-Hackus
Got Geometrodynamics? Awe, too hard to figure out? Too bad.
Electricity costs, mainly. EDF gives CERN a discount because we use so much of it, but they hike their prices up in the winter when people use more energy. Also, the winter shutdown gives people breathing space to decide what to do next, lessons to learn etc. I think in the case of LHC they could probably afford to keep it running, but there's no real point. They're going to use the time to work out how to increase from their expected pre-winter centre of mass energy of 10 TeV to 14 TeV. This is all standard accelerator practice, as far as I know.
xterm -n 8
From the BBC news website
"Full beam ahead
Engineers injected the first low-intensity proton beams into the LHC in August. But they did not go all the way around the ring.
Technicians had to be on the lookout for potential problems.
Steve Myers, head of the accelerator and beam department, said: "There are on the order of 2,000 magnetic circuits in the machine. This means there are 2,000 power supplies which generate the current which flows in the coils of the magnets."
If there was a fault with any of these, he said, it would have stopped the beams. They were also wary of obstacles in the beam pipe which could prevent the protons from completing their first circuit.
Mr Myers has experience of the latter problem. While working on the LHC's predecessor, a machine called the Large-Electron Positron Collider, engineers found two beer bottles wedged into the beam pipe - a deliberate, one-off act of sabotage.
The culprits - who were drinking a particular brand that advertising once claimed would "refresh the parts other beers cannot reach" - were never found. "
The "beer that refreshed the parts..." was an advertising slogan for Heiniken
The beer was Heineken.
The reason behind it: Apparently there were some Heiney beer bottles put into one of the parts of the LHC as an attempt of sabotage (or just random stupidity) earlier this year
Baka Drew
And the ones who lost their bets with Stephen Hawking about whether they'd find the Higgs Boson.
Isn't the real science not happening for like another 11 months?
You'll have that sometimes...
2 freight trains? You must have some really big mosquitoes where you live.
1 eV is approximately 10^(-20) K. For LHC to approach the caloric value of a soda (diet or regular, the difference is about one order of magnitude) it would need to generate particle beams with zetta-eV, i.e., 10^(21)
There are some very important points to note here about what's wrong with this statement.
It makes me angry that this was modded Informative.
Oh, the difference in calories between regular and diet sodas is closer to two orders of magnitude. That at least wasn't nonsensical, but just wrong.
So, in conclusion, they didn't test the first atomic bomb before computations were performed and Edward Teller himself wrote a report to refute his own hypothesis.
Achille Talon
Hop!
All this was was an initial test, the first attempt to circulate a beam through the collider. Nothing was actually collided.
Someone please mod up insightful or informative. My remaining mod points expired today.
The LHC was "turned on" but this does not mean it is operating anywhere near the energies that will distiguish it from past particle accelerators. Yet.
...the future crusty old bastards are already drinking the Kool-Aid.