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69challenger
10-09-2008, 05:08 PM
Scientists beaming after test of big atom smasher

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By ALEXANDER G. HIGGINS, Associated Press Writer
12 minutes ago

GENEVA - A small blip on a computer screen sent champagne corks popping among physicists in Switzerland. Near Chicago, researchers at a "pajama party" who watched via satellite let out an early morning cheer.

The blip was literally of cosmic proportions, representing a new tool to probe the birth of the universe.

The world's largest atom smasher passed its first test Wednesday as scientists said their powerful tool is almost ready to reveal how the tiniest particles were first created after the "big bang," which many theorize was the massive explosion that formed the stars, planets and everything.

Rivals and friends turned out in the wee hours at Fermilab in Batavia, Ill., in pajamas to watch the event by a special satellite connection. Joining in from around the world were other physicists — many of whom may one day work on the new Large Hadron Collider.

Tension mounted in the five control rooms at CERN, the European Organization for Nuclear Research, as scientists huddled around computer screens. After a few trial runs, they fired a beam of protons clockwise around the 17-mile tunnel of the collider deep under the rolling fields along the Swiss-French border. Then they succeeded in sending another beam in the opposite, counterclockwise direction.

The physicists celebrated with champagne when the white dots flashed on the blue screens of the control room, showing a successful crossing of the finish line on the $10 billion machine under planning since 1984.

"The first technical challenge has been met," said a jubilant Robert Aymar, director-general of CERN. "What you have just seen is the result of 20 years of effort. It all went like clockwork. Now it's for the physicists to show us what they can do.

"They are ready to go for discoveries," Aymar said. "Man has always shown he wants to know where he comes from and where he will go, where the universe comes from and where it will go. So here we're looking at essential questions for mankind."

The beams will gradually be filled with more protons and fired at near the speed of light in opposite directions around the tunnel, making 11,000 circuits a second. They will travel down the middle of two tubes about the width of fire hoses, speeding through a vacuum that is colder than outer space. At four points in the tunnel, the scientist will use giant magnets to cross the beams and cause protons to collide. The collider's two largest detectors — essentially huge digital cameras weighing thousands of tons — are capable of taking millions of snapshots a second.

It is likely to be several weeks before the first significant collisions.

The CERN experiments could reveal more about "dark matter," antimatter and possibly hidden dimensions of space and time. It could also find evidence of a hypothetical particle — the Higgs boson — which is sometimes called the "God particle" because it is believed to give mass to all other particles, and thus to matter that makes up the universe.

Smaller colliders have been used for decades to study the makeup of the atom. Scientists once thought protons and neutrons were the smallest components of an atom's nucleus, but experiments have shown that protons and neutrons are made of quarks and gluons and that there are other forces and particles.

The LHC provides much greater power than earlier colliders.

Its start came over the objections of some who feared the collision of protons could eventually imperil the Earth by creating micro black holes — subatomic versions of collapsed stars whose gravity is so strong they can suck in planets and other stars.

"It's nonsense," said James Gillies, chief spokesman for CERN, which also received support for the project by leading scientists such as Britain's Stephen Hawking.

Gillies said the only risk would be if a beam at full power were to go out of control, and that would only damage the accelerator itself and burrow into the rock around the tunnel. No one would be endangered because the tunnel is evacuated when beams are being fired.

No such problem occurred Wednesday, although the accelerator is still probably a year away from full power.

The project organized by the 20 European member nations of CERN has attracted researchers from 80 nations. Some 1,200 are from the United States, an observer country that contributed $531 million. Japan, Canada, Russia and India — also observers — are other major contributors.

Some scientists have been waiting for 20 years to use the LHC.

The complexity of manufacturing it required groundbreaking advances in the use of supercooled, superconducting equipment. The 2001 start and 2005 completion dates were pushed back by two years each, and the cost of the construction was 25 percent higher than originally budgeted in 1996, said Luciano Maiani, who was CERN director-general at the time.

Maiani and the other three former directors-general attended Wednesday's experiment.
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bigpapapump2016
10-09-2008, 07:14 PM
This is very exciting technology. Gotta love CERN

guest
10-09-2008, 08:38 PM
the sky is going to fall!

gsxr750
10-09-2008, 08:41 PM
Black hole, coming right up!

BAM
10-09-2008, 09:21 PM
It'll probably just prove that all their theories up to now are totally wrong and they have to start over from scratch.

Seth
10-09-2008, 09:52 PM
interesting, but we're gonna have to wait until late October before the first high-energy collision. And then it'll take years before we can get any valid literature on what happened. So much for getting all excited :(

Gettin'r'round
11-09-2008, 09:40 AM
Large Hadron Collider: The wait is over
27 August 2008
From New Scientist Print Edition.
Matthew Chalmers

Enlarge image

http://www.newscientist.com/data/images/archive/2671/26711301.jpg
Find out how the LHC was built

"I WILL probably cry when we see the first collision," says Bilge Demirköz. After spending the best part of a decade designing detectors and writing computer code for them, the 28-year-old physicist is yet to get her hands on real data. That's about to change. In a matter of weeks, the Large Hadron Collider at the CERN laboratory near Geneva, Switzerland, will begin amassing enough data to keep physicists off the streets for decades.

It's an emotional time for Demirköz and thousands of others who have devoted the past few years of their lives to a machine that will change our understanding of reality. The LHC is the daddy of all particle accelerators. Its collisions will generate seven times the energy of its most powerful rival, the Tevatron at Fermilab in Batavia, Illinois. By smashing together protons travelling just shy of the speed of light, the LHC will generate the largest concentration of energy ever seen in the lab - albeit in a region just billionths of the width of a speck of dust.

Smashing particles together is a tried-and-tested way of revealing what matter is ultimately made from, and what holds it together. Ernest Rutherford scored the first success nearly 100 years ago when he revealed the structure of the atom. Since then, physicists have been using accelerators to whip particles up to ever higher energies to explore even deeper into matter. At the highest energies, matter is smashed to smithereens, leaving behind fragments and energy that transform themselves into types of particles never seen before.

The LHC's microscopic fireball is the closest we can get to recreating conditions last seen less than a trillionth of a second after the big bang, when the particles and forces that shape today's universe began to emerge. The higher the collision energy, the more massive the particles created in the debris. So a host of hitherto unseen particles could materialise from the firestorm, providing physicists with important new leads in the quest to unite all the forces of nature, including gravity, into one "theory of everything".

The LHC might help us to finally crack what are arguably the biggest mysteries in physics, starting with the origin of mass and the disappearance of antimatter. It could reveal what makes up the majority of matter in the universe, the so-called dark matter that is invisible to our telescopes. And it might tell us about the very nature of space-time itself. Do extra dimensions of space exist in addition to the three we live in? Are there mini-black holes? The LHC is more than a machine. It is the intellectual quest of our age.

On 10 September the protons are set to make the first of the 11,000 or so laps they'll complete each second around the LHC's 27-kilometre ring (see diagram). Eventually proton beams travelling in the opposite direction will meet them head-on at four points in the ring where giant detectors - ATLAS, CMS, ALICE and LHCb - have been built to pore over the particle wreckage.

The universe won't be giving up its secrets to the LHC straight away, however. For a start, it will take two months just to get the proton beams colliding. Then, depending on how optimistic you are, physicists potentially face a five to 10-year slog before they know for sure whether the effort has paid off.

If nature is kind, and possibly a bit weird, the LHC will create particles we have never seen before within minutes of smashing its first protons. Finding those particles, however, is a different story. Most elementary particles fleet in and out of existence in less than a trillionth of a second, while some can pass through tens of metres of detector as if it wasn't there.

To be sure that what they're seeing is something new and not some familiar particle that blazes a similar trail, physicists will have to search the LHC's collisions for as many copies as possible. And that will take time.

In fact it could take years for CERN to announce a major discovery, especially when it comes to the Higgs boson - the earthly face of the mechanism thought to give particles their mass, and the main motivation for building the LHC in the first place. With luck, however, today's physics textbooks will start to look out of date by the end of 2009.

From day one, researchers will be scouring their detectors for distinctive patterns of energy and charge that scream "new physics". Realistically, though, they won't collect enough data in the first few months to be able to claim a discovery. What's more, no sensible scientist is going to announce a discovery until they are confident that they understand every last millimetre of their massively complex detectors.

Instead they will use this year's data - taken with a "warm-up" collision energy of 10 teraelectronvolts (TeV) - to calibrate their detectors. Then, after the machine has shut down over the New Year, they will be ready by March 2009 to pack even more protons into the beams and ramp them up to the maximum collision energy of 14 TeV.

The LHC is exploring uncharted waters and no one knows what it will throw up first. Studies suggest that the first major discovery could be confirmation of a theory called supersymmetry (SUSY), theorists' best hope for building a deeper fundamental theory of particles and forces.

SUSY predicts that all known particles have a heavier "superpartner", and that's what physicists will be hunting for in their data. "Finding evidence for SUSY would be a great intellectual triumph, given that these ideas were conceived of 30 years ago for their intrinsic theoretical beauty," says Albert De Roeck, who leads the search for new physics at the CMS experiment. What's more, the lightest of the proposed supersymmetric particles is a candidate for dark matter - an invisible entity that appears to outweigh normal matter by a factor of five.

If superpartners exist and weigh less than about 1 TeV, as the simplest versions of supersymmetry predict, then the LHC should produce them by the hundred next year. "It's a damn difficult analysis, but if SUSY exists then claiming a discovery in 2009 is absolutely our target," says Oliver Buchmüller of the CMS experiment. "If you've built a $10 billion machine you're allowed to be optimistic."

Optimism is an apt word, because researchers hunting for supersymmetric particles will be looking for the invisible. The lightest supersymmetric particle, into which the heavier ones decay, interacts so weakly with matter that it will fly straight out of the detectors, carrying energy and momentum with it. Physicists will look for this missing energy as a possible sign of supersymmetry. Yet things aren't even that simple. Tiny gaps between the thousands of segments in the giant detectors or a few broken electronic connections could conjure the illusion of a Nobel prize-worthy discovery.

Even if missing energy is genuinely detected, there will be no guarantee that it is due to supersymmetry. Missing energy could also be a sign that a particle has disappeared into an extra dimension, taking its energy with it. To tell these scenarios apart, researchers will have to measure the "spin" of the mystery object, which will require yet more data and further painstaking analysis.

Help could come from an unexpected corner. This time next year, just as researchers on the multi-purpose experiments ATLAS and CMS are getting to know their apparatus and competing hard to discover superpartners and other new particles, a smaller detector called LHCb could offer some important clues.

LHCb has been designed to take exquisitely detailed measurements of particles called B mesons, which have been studied at other accelerators. B mesons exist for a fleeting moment before decaying into lighter particles. SUSY might infiltrate this process and subtly change the B meson's properties. So by scrutinising vast numbers of them and comparing their properties with theoretical models, LHCb might be able to infer the existence of particles that are far too heavy to be produced directly at the LHC.

Unfinished business
Supersymmetry and extra dimensions are all very well, but the LHC's primary goal concerns unfinished business with the standard model of particle physics, our best understanding to date of matter and forces. The theory is built on the well-tested idea that the electromagnetic and weak forces are united at high energies, as they were in the very early universe as the electroweak force. But this only holds if all particles are massless - which is obviously not the case today. The Higgs boson is associated with the process thought to break the electroweak force and give rise to particle masses.

The chances of finding the Higgs depend on how heavy it is - something the standard model does not predict. Some clues come from previous experiments, though. No Higgs bosons showed up at the Large Electron Positron collider, which once occupied the same tunnel as the LHC, and so physicists have ruled out a Higgs weighing less than 114 gigaelectronvolts (GeV). And earlier this month, researchers at the Tevatron excluded a Higgs with a mass of exactly 170 GeV.

A heavy Higgs in the range 140 to 500 GeV could turn up sooner than a lighter one - perhaps by late 2009. That's because a hefty Higgs would be heavy enough to decay into relatively massive particles called W and Z bosons, which would stand out against the profusion of other particles.

Spotting a lighter Higgs would be much trickier. Fewer of them are expected to be produced and there are many more lookalike processes to worry about. Physicists will probably need to wait until 2011 to be confident of the discovery of a 120 GeV Higgs, and a further year if it's as light as 115 GeV. By then it is possible that the Tevatron will have bagged a few Higgs bosons of its own, though not enough to claim outright discovery.

With some luck, by late 2010 physicists could find themselves in a playground of Higgs and supersymmetric particles, finally understanding the origin of mass and the nature of dark matter. Meanwhile, the LHC should be well on its way to reaching its design performance, perhaps producing mini-black holes by the thousand and putting other exotic theoretical ideas through their paces.

Or the story could turn out horribly different. "The nightmare scenario is no Higgs, no supersymmetry, no anything apart from known particles," says Chiara Mariotti, co-leader of the search for the Higgs on CMS. "That would mean rethinking everything from scratch." It would also turn a planned LHC upgrade in 2012 - which will allow 10 times as many collisions and enable particles with masses up to about 6 TeV to be discovered - into a desperate last bid to stop the LHC from being the last high-energy particle collider ever built. "Some theorists say this would be interesting," says De Roeck. "But it's a horror scenario for experimentalists and we'd probably never listen to theorists again."

It's an extremely unlikely outcome, though. Without the Higgs or something else new kicking in around 1 TeV, the standard model would have fallen apart long before now and, despite its shortcomings, it has been remarkably successful so far. That "something else" may not be a crowd pleaser like the Higgs and it could take years to fathom out, but the LHC will still have done its job.

Beyond that, anything is a bonus. While the theoretical ground for supersymmetry is rock solid, there are no experimental hints that it exists - unlike with the Higgs. Other phenomena are on much weaker foundations. "If you soberly ask the people who work on it, they say that they would be astounded if baby black holes or extra dimensions ever showed up," says theorist Ben Allanach at the University of Cambridge.

Particle physicists are about to enter the unknown using the most complex instrument ever built. Despite their sales talk, most secretly hope that something totally unexpected happens as soon as the collisions begin. With at least 6000 individuals vying to get their names attached to a discovery, rumours about the findings are sure to be headlines before long.

The wait is almost over. Beliefs and wish-lists will soon be safely stowed. It's time to see what nature is really made of.

Vegas
21-09-2008, 08:25 PM
http://www.hasthelargehadroncolliderdestroyedtheworldyet. com/

BAM
21-09-2008, 08:28 PM
I heard it is broken.

Gettin'r'round
22-09-2008, 09:44 AM
I heard it is broken.

Yup. It's now months behind as it takes that long to cool it to 1degree above K

Bowlcut
22-09-2008, 08:35 PM
It'll probably just prove that all their theories up to now are totally wrong and they have to start over from scratch.

Could be true.
Think it is going to provide the best insights on trying to unify Quantum Mechanics with General Relativity and find the GUT.

ManInTheBox
23-09-2008, 12:30 AM
You may have to start from scratch in such a scenario, but hey such a scenario can be a beneficial one - the only 100% assurance of an abductive discovery being true or false is: false. If a conclusion is false it will prove a denial of the premises, in this case, a hypotheses. However I'm drifting off here into Logic discussion. ...

The point is that at least we'll finally know it is wrong and be able to divert our attention towards a more plausible hypothesis. Also, being able to rethink the realm of theorretical physics studying under such pristine conditions, I would imagine it possible to develop an understanding rather quickly.

However, of course, I believe the LHC will prove certain modern theories of physics, such as the higgs boson. I take the position that there must be an explanation of why massless particles are heavier than they ought to be. Many theories are assumed a rather high probability of being true, given current observation.

Whatever the case, I believe it will reveal many interersting things about our universe. I discredit doomsday theoriest - the earth and moon get hit by MANY times stronger cosmic rays and we haven't been obliterated as of yet.

Anthropic Principle: The universe is the way we observe it, because if It was not, no creature would able to exist in it.