What Do You Think?

[troach]

this is an interesting write up about the LHC
there are a lot of links within the pages that give some more detailed information.

it is a bit old but some of the information is worth reading.




copied from:
http://www.msnbc.msn.com/id/24525554/ns/technology_and_science-science/t/super-smasher-targets-massive-mystery/



By Alan Boyle
Science editor

msnbc.com
9/8/2008


Switzerland — In the beginning was the big bang.

God may have been around before then — but as far as scientists are concerned, the big bang is as far back as they can go. And to get back there, they're getting ready to blast subatomic particles so energetically that the extreme conditions of the freshly born universe will be re-created on Earth.

Will those "little big bangs" crack age-old scientific mysteries? Or, despite repeated assurances from the world's top experts, will they create black holes that could gobble up the planet? After decades of preparation, scientists are finally switching on a machine that will separate the facts from what is plainly science fiction.

The machine is the $10 billion Large Hadron Collider, or LHC — the most powerful, most expensive particle-blaster ever invented. On Wednesday, Europe's CERN particle-physics lab is due to start shooting beams of protons through the LHC's 17-mile-round (27-kilometer-round) ring of tunnels beneath the French-Swiss border, near Geneva.

It will take months for the machine to reach full power. But eventually, those protons will be whipped up to 99.999999 percent of the speed of light, slamming together with the energy of two bullet trains colliding head-on. Underground detectors as big as cathedrals will track the subatomic wreckage on a time scale of billionths of a second. Billions of bits of data will be sent out every second for analysis.

As big as the numbers surrounding the LHC are, the mysteries it was built to address are bigger:

•What was the newborn universe made of?
•What causes things to have mass?
•Why is most of that mass hidden?
•Where did all the antimatter go?
•Is our entire universe a mere sliver of all that is?

"The LHC is the most powerful microscope that's ever been built," said John Ellis, a theoretical physicist here at CERN. "It will be able to explore the inner structure of matter on a scale that is 10 times smaller than anyone's been able to do before."

Ellis said the LHC also serves as "the most powerful telescope ever built," even though it looks inward rather than outward.

"We know that the way elementary particles interacted with each other controlled the very early universe," he explained. "So with the LHC we are able to, in some sense, re-create the conditions that existed in the universe when it was just a fraction of a second old — the sort of thing that the optical telescopes just can't see."

What's the point?
Past experiments in particle physics have yielded scores of practical spin-offs, ranging from new medical therapies to high-tech industrial materials — and even the World Wide Web, which you're using to read this report. But the potential for spin-offs isn't why more than 10,000 researchers around the world are looking forward so anxiously to the LHC.

"People ever since the ancient Greeks – and probably a long time before that – have wanted to understand how matter is made up, how it behaves, where the universe comes from,” said Ellis, surrounded in his office by stacks of research papers. “And so we are responding to that continuing human urge.”

The quest is not without controversy: Scientists say there's a chance that the LHC could create microscopic black holes, a phenomenon never before observed on Earth. They hasten to add that the tiny singularities will instantly pop out of existence, but that hasn't stopped critics from trying to block the collider's startup. Two of the critics have filed suit in federal court in Hawaii, seeking the suspension of LHC operations until more studies are done.

Responding to the critics, CERN has issued a series of reports explaining why the LHC will pose no threat. Ellis was one of the report's authors. "If the LHC were to make microscopic black holes, it would be tremendously exciting — and no danger," he said.

The 62-year-old London native has spent more than half his life at CERN, delving into topics ranging from dark matter to the theory of everything. Once the LHC is up and running, he expects to find out whether the theories he and other physicists have developed over all those years lead to solid evidence — or lead to a scientific dead end.

“Theoretically, that would be the most interesting possibility, because it would really mean that we had to tear up our notebooks of the last 45 years and start more or less from scratch,” Ellis said.

The God Particle

The theory described in all those notebooks is known as the Standard Model, which ranks among the scientific world's most successful theories. The Standard Model lays out a menagerie of subatomic particles and their interactions — and provides the basis for inventions ranging from television sets to microwave ovens to nuclear bombs.


Only one elementary particle predicted by the Standard Model has not yet been detected: the Higgs boson, which is thought to interact with other particles to give them mass. Without the Higgs, the big bang might have been an insubstantial flash in the pan — all energy, and no mass. Or so the theory goes.

The elusive Higgs boson looms so large as a gap in the Standard Model that Nobel-winning physicist Leon Lederman wrote a book about it called "The God Particle." (He joked that he wanted to call it the "Goddamn Particle," but his editor wouldn't let him.)

"This is in some sense the holy grail of particle physics, to find this missing link in the Standard Model," Ellis said. "So that's one thing that we're really looking forward to with the LHC. In fact, back when we persuaded the politicians to stump up the money to build the thing, that's probably what we told them."

Not even the LHC will be able to spot the Higgs boson directly. Instead, physicists will have to infer its existence through an analysis of the other particles that should be created when it decays. It's not an easy task, but Ellis believes the evidence should turn up within a year or two of the machine's startup.

Even that won't mark the end of the quest. Ellis compared the Higgs boson to a doorway that should lead beyond the Standard Model.

"I don't think that the Higgs door, if you like, is just closing off the room, and there is nothing beyond," he said. "I believe there's going to be a lot more physics beyond. What it's going to be, I don't know. Maybe it's supersymmetry. Maybe space has additional dimensions. Maybe it's something that we haven't thought of yet. I certainly hope it's something we haven't thought of yet. It would be great to come across a real surprise."

But Ellis and his colleagues at CERN have two nagging concerns in the back of their minds: What if somebody else finds the magic door first? Or what if they spent all these billions of dollars and there's no Higgs particle at all?

A competitive twist

Fifteen years ago, when Leon Lederman wrote "The God Particle," he thought the Higgs boson would be found in the Superconducting Super Collider, a project that was just getting started in Texas. That machine would have been four times as powerful as the LHC — but when the costs started running far beyond the initial estimates, Congress killed the program.

Over the decade that followed, U.S. scientists weren't just waiting for the LHC to be built: The focus shifted to the Tevatron collider at Fermilab in Illinois, which theorists figured might have just enough punch to pick up the Higgs' trail.

Last year, researchers at Fermilab passed the word that they had found some interesting data — readings that hinted at the presence of the Higgs but weren't yet solid enough to publish. That added a competitive twist to the grail quest.

"The longer we wait, the higher the probability that Fermilab discovers something that we wouldn't mind discovering ourselves here," Jos Engelen, CERN's chief scientific officer and deputy director general, said last year.

Beyond the God Particle

What if physicists don't find the God Particle they are expecting to see? Ellis acknowledged that was a possibility. "This might be a little bit difficult to explain to our politicians, that here they gave us 10 billion of whatever, your favorite currency unit, and we didn't find the Higgs boson," he said.

But Ellis has faith that even then, there'd be something to discover — maybe something even weirder and more wonderful than the Higgs boson.


"Probably the most likely option then might be extra dimensions," Ellis said. "And there are some ideas where if you have some additional dimensions of space, you could somehow do the job that the Higgs does in the Standard Model."

For years, string theorists have noted that their equations come out better if they assume that the universe has nine or 10 spatial dimensions instead of the three we can perceive. The LHC could provide the first evidence of those extra dimensions: Some theorists say the collisions could produce anomalously heavy particles, suggesting that part of their momentum was going into the extradimensional realm. Harvard physicist Lisa Randall estimates that the LHC could nail down the evidence for extra dimensions in five years.

Other theorists have focused on the idea that every subatomic particle should have an as-yet-undetected "supersymmetric" partner that mirrors many of the characteristics of the particles we know, but is dramatically different in other respects. The partners would have greater masses and a different spin, for example.

To date, no actual evidence of supersymmetry has been found. But if supersymmetric particles don't exist, then a lot of the theories that look beyond the Standard Model would have to be thrown out.

If supersymmetric particles do exist, they could account for a large part of the universe's dark matter. That's the 90 percent of all matter that scientists can detect only by its gravitational effect — a puzzle that has bedeviled astronomers for decades. "There are good reasons to think that these dark matter particles, if they exist, will be observable in the LHC," Ellis said.

Exploring the big-bang frontier

One of the LHC's detectors, known as ALICE, is devoted to studying the stuff that the universe was made of less than a billionth of a second after the big bang. Earlier experiments have hinted that the stuff was a super-hot liquid consisting of subatomic particles known as quarks and gluons.

For one month out of every year, the LHC will switch from smashing protons to smashing heavy lead ions, in an effort to re-create that quark-gluon soup and let ALICE analyze the recipe.

Yet another detector, LHCb, will study the tracks of particles containing specific types of quarks and antiquarks. The Standard Model predicts that equal amounts of matter and antimatter should have been produced in the big bang — but today, we see hardly any antimatter in nature. That's a good thing, because matter and antimatter annihilate each other when they come in contact, leaving pure energy behind.

LHCb will follow up on earlier experiments that suggest matter won out over antimatter because they somehow decay in different ways.

And then there are the wild cards in the deck: Could the LHC really create black holes or exotic forms of matter? What about all these claims that the world is in peril?


Super-smasher targets massive mystery
Chapter 1: Particle collider comes close to the big bang on a small scale

[troach]

http://www.msnbc.msn.com/id/24556999/ns/technology_and_science-science/t/discovery-or-doom-collider-stirs-debate/


Discovery or doom? Collider stirs debate
Chapter 2: Cutting through the hype over black holes and future benefits


By Alan Boyle
Science editor

msnbc.com msnbc.com
9/8/2008

Will the Large Hadron Collider destroy the world, or help the world?

As the atom-smasher at Europe's CERN research center is readied for its official startup near Geneva on Wednesday, researchers might wish that the general public was captivated by the quest for the Higgs boson, the search for supersymmetric particles and even the evidence for extra dimensions.

But if the feedback so far is any guide, the real headline-grabber is the claim that the world's most powerful particle-smasher could create microscopic black holes that some fear would gobble up the planet.

The black-hole scenario is even getting its day in court: Critics of the project have called for the suspension of work on the European collider until the scenario receives a more thorough safety review, filing separate legal challenges in U.S. federal court and the European Court of Human Rights.

The strange case of the planet-eating black hole serves as just one example showing how grand scientific projects can lead to a collision between science fiction and science fact. The hubbub also has led some to question why billions of dollars are being spent on a physics experiment so removed from everyday life.

Why do it?
Michio Kaku, a theoretical physicist at the City College of New York, acknowledged that people often ask about the practical applications of particle physics. Even if physicists figure out how a particle called the Higgs boson creates the property of mass in the universe, how will that improve life on Earth?

"Sometimes the public says, 'What's in it for Numero Uno? Am I going to get better television reception? Am I going to get better Internet reception?' Well, in some sense, yeah," he said. "All the wonders of quantum physics were learned basically from looking at atom-smasher technology."

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.Kaku noted that past discoveries from the world of particle physics ushered in many of the innovations we enjoy today, ranging from satellite communications and handheld media players to medical PET scanners (which put antimatter to practical use).

"But let me let you in on a secret: We physicists are not driven to do this because of better color television," he added. "That's a spin-off. We do this because we want to understand our role and our place in the universe."

About those black holes ...
The black holes that may (or may not) be generated by the Large Hadron Collider would have theoretical rather than practical applications.

If the collider's detectors turn up evidence of black holes, that would suggest that gravity is stronger on a subatomic scale than it is on the distance scales scientists have been able to measure so far. That, in turn, would support the weird idea that we live in a 10- or 11-dimensional universe, with some of the dimensions rolled up so tightly that they can't be perceived.

Video: Big Bang collider could test theories—and nerves

Some theorists say the idea would explain why gravity is so much weaker than the universe's other fundamental forces — for example, why a simple magnet can match the entire Earth's gravitational force pulling on a paper clip. These theorists suggest that much of the gravitational field is "leaking out" into the extra dimensions.

"It will be extremely exciting if the LHC did produce black holes," CERN theoretical physicist John Ellis said. "OK, so some people are going to say, 'Black holes? Those big things eating up stars?' No. These are microscopic, tiny little black holes. And they’re extremely unstable. They would disappear almost as soon as they were produced."

Not everyone is convinced that the black holes would disappear. "It doesn't have to be that way," said Walter Wagner, a former radiation safety officer with a law degree who is one of the plaintiffs in the federal lawsuit. Despite a series of reassuring scientific studies, Wagner and others insist that the black holes might not fizzle out, and they fear that the mini-singularities produced by the Large Hadron Collider will fall to the center of the earth, grow larger and swallow more and more of Earth's matter.

Ellis, Kaku and a host of other physicists point out that cosmic rays in space are far more energetic than the collisions produced in the Large Hadron Collider, and do not produce the kinds of persistent black holes claimed by the critics. In the most recent report, CERN scientists rule out the globe-gobbling black holes and the other nightmares enumerated in the lawsuit, even under the most outlandish scenarios. Wagner remains unconvinced, however.

"I don't think the knowledge we are going to acquire by doing such an experiment outweighs the risk that we are taking, if we can't quantify that risk. ... We need to obtain other evidence," he said.

Strangelets, monopoles and more

Black holes aren't Wagner's only worry: He also is concerned that when the collider creates a soup of free-flying quarks, some of those quarks might recombine in a hazardous way — creating a stable, negatively charged "strangelet" that could turn everything it touches into more strangelets.

The lawsuit also suggests that magnetic monopoles — basically, magnets with only a north or a south pole, but not both — could be created in the collider and wreak havoc.

Physicists point out that such phenomena have never been seen, either in previous collider experiments or in the wide cosmos beyond Earth.

"The experiments that we will do with the LHC have been done billions of times by cosmic rays hitting the earth," Ellis said. "They're being done continuously by cosmic rays hitting our astronomical bodies, like the moon, the sun, like Jupiter and so on and so forth. And the earth's still here, the sun's still here, the moon's still here. LHC collisions are not going to destroy the planet."

But how will all those collisions benefit the planet?

"We don't justify CERN or other big particle accelerators on the basis of spin-offs or technology transfer," Ellis said. "Of course, we do have programs for that. Personally, I believe that the most important knowledge transfer that we can make is by training young people who then maybe go off and do something else. I think that's probably more important than some particular technological widget that we may develop.

"I think the primary justification for this sort of science that we do is fundamental human curiosity," Ellis said. "It's true, of course, that every previous generation that's made some breakthrough in understanding nature has seen those discoveries translated into new technologies, new possibilities for the human race. That may well happen with the Higgs boson. Quite frankly, at the moment I don't see how you can use the Higgs boson for anything useful."

Kaku takes a different view: He said physicists will have to do a better job of explaining the potential payoffs if they expect taxpayers to keep covering the multibillion-dollar cost of exploring the scientific frontier. He pointed to the example of the Superconducting Super Collider — a project planned for Texas that would have been bigger than the Large Hadron Collider, but was canceled by Congress after $2 billion had been spent.

"After that cancellation, we physicists learned that we have to sing for our supper," Kaku said. "The Cold War is over. You can't simply say 'Russia!' to Congress, and they whip out their checkbook and say, 'How much?' We have to tell the people why this atom-smasher is going to benefit their lives."

Forecasting future benefits
If past physics experiments are any guide, the potential payoffs would likely come in three areas, Kaku said:

•Telecommunications: The challenge of dealing with all the data created by past experiments led to the creation of the World Wide Web at CERN in 1990. In a similar way, the Large Hadron Collider could usher in an era of global distributed computing and more efficient mass data storage. A better understanding of the subatomic world could lead to breakthroughs in quantum computing and super-secure communication.


•Medicine: Particle accelerators are already playing a fast-rising role in cancer treatment and medical imaging . New technologies developed for the Large Hadron Collider could well find their way into hospitals of the future. The ultrasensitive photon detector built for the LHCb experiment is a prime example, said the project's deputy spokesperson, Roger Forty. "I think there will be some cross-pollination with medical applications," he told msnbc.com.


•Energy: Kaku suggested that the insights gained from the Large Hadron Collider could be applied to developing new energy sources in the decades ahead — such as controlled fusion power. Those microscopic black holes might even play a long-range role in the energy quest. "Some people think that maybe black holes in outer space may be a source of energy for future civilizations," he said.

Looking even farther ahead, Kaku noted that a deeper understanding of the universe has always led to technological leaps. Harnessing mechanical power led to the steam engine and the industrial revolution of the 19th century. The unification of electricity and magnetism led to computers, lasers and other 20th-century wonders. Unlocking the secrets of the atom led to the triumphs and terrors of the nuclear age.

"Human history has been shaped by the progressive unraveling of gravity, electricity and magnetism, and the nuclear force," Kaku said. "Now we are at the brink of the granddaddy of all such unifications ... the unification of all forces into a super force. We think the super force is superstring theory, a super force that drove the big bang, that created the heavens and the earth, that drives the sun, that makes all the wondrous technologies of the earth possible."

Will that great revelation come from the LHC? Even Kaku thinks that would be too much of a giant leap. "The Large Hadron Collider will not open up a gateway to another universe," he said. "It will not open up a hole in space. But it will try to nail down the equations which would allow perhaps an advanced civilization to do precisely that, to manipulate the fabric of space and time."

How will the machine do that? Ironically, it takes bigger and bigger machines to unlock the smallest subatomic mysteries — and the Large Hadron Collider is the biggest Big Bang Machine ever built. With its tangles of wiring, twists of plumbing and 17 miles of supercooled magnets, the machine may well rank as one of the engineering wonders of the 21st century.

[troach]

http://www.msnbc.msn.com/id/26439957/ns/technology_and_science-science/t/scientists-turn-biggest-big-bang-machine/

Scientists turn on biggest ‘Big Bang Machine’

Chapter 3: After 14 years of work, atom-smasher comes to life amid hoopla


By Alan Boyle
Science editor


9/10/2008

After 14 years of preparation, a new scientific wonder of the world opened for business Wednesday with the official startup of Europe's Large Hadron Collider.

The $10 billion particle accelerator is the biggest, most expensive science machine on earth, designed to probe mysteries ranging from dark matter and missing antimatter to the existence of extra, unseen dimensions in space.

Scientists, journalists and dignitaries watched from the control room at Europe's CERN particle-physics center on the French-Swiss border, near Geneva, as beams of protons were sent all the way around the collider's 17-mile (27-kilometer) underground ring of supercooled pipes for the first time.

"Today is a great day for CERN," the organization's director general, Robert Aymar, told the crowd in the control room as the startup process began.

Controllers checked the alignment of the beam as barriers were removed at each stage of the route. Applause and shouts greeted every report of progress along the 330-foot-deep (100-meter-deep) tunnel — climaxing when the beam made its first full clockwise circuit, less than an hour after it was turned on.

"It’s a fantastic moment," Lyn Evans, the project leader for the Large Hadron Collider, said afterward. "We can now look forward to a new era of understanding about the origins and evolution of the universe.”

As champagne flowed in the control room, former CERN chief Luciano Maiani noted that the money spent on the project over 14 years was a mere fraction of the $40 billion that China spent for this summer's Olympic Games in Beijing. "These are the Olympics of science," CERN spokeswoman Paola Catapano replied during a Webcast interview.

Hours later, the LHC's counterclockwise proton beam made its first-ever circuit. The next steps in the process will be to fine-tune the beams and bring them together for their first collisions. It will take weeks for the collider to go through its commissioning process, and the LHC isn't expected to reach full power until next year.

‘First Beam,’ first celebration

Even though the first scientific results are months away, CERN used Wednesday's "First Beam" events as a high-profile occasion for celebration. For the more than 10,000 scientists, engineers and other workers involved in the project, the Large Hadron Collider represents a revolutionary new research opportunity as well as an unprecedented engineering achievement.

Video: The biggest physics experiment

"The combination of the size, scale, complexity and technology — well, the comparison I always use is the pyramids," Peter Limon, a U.S. physicist from Fermilab who played a part in building the device, said during a pre-startup walkthrough. "This is what we do today comparable to the pyramids of 4,000 years ago."

The LHC is designed to do things the pyramid's builders never imagined.

Once the machine is in full operation, two streams of invisible protons will be whipped up in opposite directions around an underground racetrack to 99.999999 percent of the speed of light. When the two waves of protons slam into each other, scientists expect particles to melt into bits of energy up to 100,000 times hotter than the sun's core — a state that should replicate what the entire universe was like just an instant after it came into being.

How can the Large Hadron Collider possibly perform such feats? That's where the wonder begins.

Going down ...

No one was allowed in the underground tunnel for Wednesday's maiden run, but a visit during the final phases of the LHC's construction provided an inside look at the wonder at work.

During the seven-year construction phase, components of the collider and its detectors had to be lowered down piecemeal from CERN's assembly halls, then put together in underground caverns as big as cathedrals.

Although the scale of the project is impressive, these cathedrals are no gleaming shrines to science: Our trip felt more like going into the bowels of a well-worn power plant or subway system. That's because most of the facility was actually carved out in the 1980s for an earlier particle-smasher called the Large Electron Positron collider, or LEP. CERN has spent the past seven years remodeling the space for the Large Hadron Collider.

Steven Nahn, a physicist at the Massachusetts Institute of Technology, conducted research at CERN during the LEP era. "They stole our tunnel, that's the way I see it," Nahn joked as Limon showed us around.

For years, Nahn, Limon and thousands of other researchers have pitched in on the design and assembly of the LHC's instruments, forsaking quiet laboratories for the din of the construction site — as well as the occasional industrial mishap.

The LHC tunnel: Misbehaving magnets

Limon is a veteran of Fermilab's Tevatron, which had been the world's most powerful collider but is being dethroned by the LHC. At full power, the proton beams at the LHC will run into each other with the force of two 400-ton bullet trains going 100 mph. That amounts to 14 trillion electron volts, or about seven times the Tevatron's maximum power.

To bend those subatomic bullet trains into a circular path requires a chain of more than 1,800 superconducting magnets that have been chilled so close to absolute zero that they're colder than the average temperature of outer space (1.9 Kelvin, or 456.3 degrees below zero Fahrenheit).

Some of those magnets have to be collimated to focus the beams precisely at the ring's four collision points, like a telescope focusing light onto its mirrors. Drawing on its experience from Tevatron, Fermilab was put in charge of providing many of those magnets. But back in March 2007, a design flaw led to a violent breakdown during a cooldown test. The supports that held the magnet in place came loose with a loud bang and a cloud of dust.

"Everybody ducked about two seconds after it happened," Limon recalled.

The LHC's scheduled startup had to be delayed 10 months to install and test a fix for the faulty magnets. Even with the fix, there's no guarantee that the magnetic field will always hold. A runaway proton beam could blast right through its helium-cooled pipeline and kill anyone who got in its way. That's why the tunnel is sealed off for each run. If anything goes wrong, a computer-controlled system will shut down the collider and send the errant beam down a blind alley within milliseconds.

However, if everything goes right, each pulse of protons will whip around the ring 11,000 times a second, traveling the equivalent of a trip to Neptune and back before they slam into the protons going the other way at four points around the ring. Four main detectors will watch what happens next.

ATLAS and CMS: What the detectors do

For millennia, people have studied how things work by breaking them apart and watching what happens to the pieces. Physicists started doing that with atoms about 90 years ago, confirming that atoms were composed of electrons, protons and neutrons — plus a menagerie of other particles they never expected to find. (After the discovery of the muon, physicist Isidor Rabi famously exclaimed, "Who ordered that?")

Physicists determined that protons, neutrons and many of the other particles were built up from even more fundamental constituents known as quarks. The particles built up from quarks are classified as hadrons, and that's where the LHC's name comes from: It's a large collider that smashes hadrons together.

So what will come out of those tiny, trillion-degree smash-ups? The LHC will look for exotic high-energy particles that supposedly came into existence just after the big bang — for example, the Higgs boson (which is thought to give other particles their mass) or supersymmetric particles (which may account for much of the universe's dark matter).

These particles can't be detected directly, because they interact so weakly with ordinary matter. Instead, the LHC's detectors will track how those particles decay into more easily detectable particles as they fly out from the collision point.

Video: Supercollider conducts first tests

It's like reconstructing the scene of a crime from forensic evidence: Scientists will try to track down the usual suspects (or, they hope, the extremely unusual suspects) by analyzing the subatomic evidence that the culprits leave behind.

To solve their mysteries, the LHC's scientific sleuths will use the latest and greatest tools of the trade, built at a cost of billions of dollars. The two main detectors — ATLAS ( A Toroidal LHC Apparatu S) and CMS ( Compact Muon Solenoid) — are structured like the layers of an onion to spot different kinds of particles:

•Trackers: Both detectors have tracking devices at the center to follow the paths of short-lived particles.
•Calorimeters: The next layers are two different types of calorimeters that measure the energies of the particles given off. One captures electromagnetic energy, while the other captures the energy from particles such as protons, neutrons and pions.
•Magnets: Huge magnets are built into each detector to bend the paths of the particles so they can be identified by their charge.
•Muon detectors: The outer layers of the detector track the paths of muons, particles that can't be stopped by any of the inner layers.

Probing the smallest scales of matter requires some of the biggest machines ever devised. ATLAS is the largest of all detectors, measuring 151 feet long and 82 feet high — bigger than your typical apartment building.

"It has an awful lot of free space inside," CERN theoretical physicist John Ellis explained. "The reason for that is, they want to be able to measure particles which come out of the collision ... even if the interior of the detector is so clogged with collision products they can't measure them properly there."

Over on the other side of the LHC's ring, CMS takes up less than half as much space as ATLAS but weighs almost twice as much. It contains more iron than the Eiffel Tower, built into alternating magnetized layers with particle detectors like a metallic jelly roll. CMS' built-in magnets and its expensive fine-resolution silicon tracker are part of a different strategy to do the same things that ATLAS does.

"You get big arguments between the ATLAS guys and the CMS guys as to which is the best way to measure these particles," Ellis said. "ATLAS is going to bend them that way, CMS is going to bend them this way, and we'll see in a few years' time which is the better idea."

ALICE: The big bang in the machine

ATLAS and CMS get most of the attention, but the contraption that best merits the title of "Big Bang Machine" is about a mile (1.5 kilometers) down the road from ATLAS. The ALICE detector ( A Large Ion Collider Experiment) is designed exclusively to study the stuff that the universe was made of less than a millionth of a second after the big bang.

ALICE will run for only about a month out of every year, conducting experiments that will require the collider to switch over from smashing protons to smashing lead ions, which are 100 times heavier than protons. The high-energy collisions should blast those ions so thoroughly that, for just an instant, they turn into a plasma of free-flying quarks plus gluons, the particles that usually bind quarks together.

Past experiments indicated that the quark-gluon plasma behaved like a liquid. When ALICE gets up and running, "then maybe we reach the gas phase," said Jurgen Schukraft, CERN's spokesperson for the ALICE experiment. That would be something never before seen in the cosmic scheme of things.

LHCb: The mystery of antimatter

The fourth detector is also designed to answer a specific cosmic question. LHCb will study particles containing particular "flavors" of quarks and antiquarks, known as B mesons and anti-B mesons, with the aim of figuring out why matter has a huge edge over antimatter in our universe.

Earlier studies revealed that the particles and antiparticles decayed differently, which runs counter to the idea that matter and antimatter should be in symmetry. LHCb will follow up on those studies, using a battery of high-tech detectors that are lined up on one side of the collision point. Among those instruments are a tracker that can locate particles with a precision of 10 microns, or a tenth the width of a human hair.

Two smaller experiments round out the ring: LHCf, which studies cosmic-ray-like events near ATLAS; and TOTEM, which measures the effective size of protons using a detector near CMS.

The Grid: Getting out the data

The LHC is designed to produce as many as 600 proton collisions per second, and that creates a flood of digital data that gushes out from the detectors' wiring. If you were to put all the data from one of the main detectors onto CDs, the stack of disks would pile up to the orbit of the moon in six months. The challenge is to pick out only the most promising readings.

Each of the detectors uses "triggers" to pick out the good stuff. Only about 100 events per second are sent to thousands of computers and tape drives at CERN for storage. It's like narrowing down that moon-high stack of CDs to a stack that's only 6 miles high — which is still high enough for a transcontinental jet to run into.

To get the data out to researchers around the world, CERN has set up a multi-tier computer network called the Grid. Digital information goes out to the "Tier 1" data centers on a fiber-optic network at a rate of up to 10 gigabits per second — or roughly 1,000 times the speed of a typical cable Internet connection.

If the system works, it could set the model for future computing — not only for physics but also for other high-end applications such as climate simulation, genetic analysis and petroleum prospecting. Just as the World Wide Web was the best-known spin-off from CERN's LEP experiment back in the 1990s, the Grid could well become the LHC's most visible legacy.

Magnet for innovation

Who will benefit the most from that legacy? The Grid may distribute the data across the world — but it's hard to argue with the idea that Europe's 21st-century wonder of the world will serve as a magnet for innovation over the next decade.

That has sparked more than a few cases of "collider envy" among American researchers, and some worry about the prospects of a reverse brain drain. Michio Kaku, a theoretical physicist at the City College of New York, is already noticing a trend in his colleagues' travel plans.

"They're going where the action is, and that is Europe," Kaku said.

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http://www.msnbc.msn.com/id/24748826/ns/technology_and_science-science/t/europe-leaps-ahead-physics-frontier/


Europe leaps ahead on physics frontier
Chapter 4: Collider becomes international magnet for brain power


By Alan Boyle
Science editor

msnbc.com
updated 9/11/2008


MEYRIN, Switzerland — Adam Yurkewicz was born, raised and schooled in New York state, intending to become an engineer. But in 1996, during his junior year in college, he got hooked on quantum electrodynamics and other wild ideas from the frontiers of physics — and he's never been the same since.

To follow his vocation as a particle physicist, Yurkewicz has been a grad student in Michigan, an experimenter in Illinois, a postdoctoral researcher in New York, and other things in between. He is now working on the ATLAS experiment at the Large Hadron Collider, and living in France with his New York-born wife and their first child.

In short, Yurkewicz is a science nomad.

"I don't think I've lived in the same place for more than a year in the last 10," he said as he sat at a table outside the cafeteria at Europe's CERN particle-physics center, just outside Geneva.

There are a lot of brainy nomads hanging around CERN's cafeteria nowadays. The patrons hail from all over the United States, from Canada, from Russia, from Japan, from China, and of course from across Europe. "It's like a mini-U.N.," Yurkewicz said.

Changing of the guard

The buzz of activity at CERN's Swiss campus dramatically illustrates a changing of the guard on the frontier of physics, with Europe taking over from the United States. For the past 14 years, Europeans have taken the lead role in building and financing the $10 billion Large Hadron Collider, which was started up on Wednesday. The U.S. federal government kicked in $531 million for construction.

The LHC is just this week's most obvious example of Eurocentrism in science: Less than 200 miles (300 kilometers) away, an even costlier international physics project, the $13 billion ITER fusion research center, is just getting started in southern France. And European officials are currently considering how to move forward with yet another fusion project, the $1 billion HiPER laser-fusion facility.

Meanwhile, in the United States, physicists were shocked last December to see Congress pull back on research spending, to the tune of $94 million. Financial support for ITER was virtually wiped out. It took months for some of that money to be restored in a supplemental funding bill — and while Congress dithered, scores of research positions were lost.

For decades, American know-how has benefited mightily from a "brain drain" of talent from Europe. It started in earnest when German physicist Albert Einstein and many of his colleagues fled the Nazi threat in Europe in the 1930s and relocated in the United States. That flow of expertise continued right through the space effort of the 1960s and '70s as well as the telecommunications revolution of the '80s and '90s.



Adam Yurkewicz, a postdoctoral researcher for Stony Brook University in New York, lives in France and works on the Large Hadron Collider's ATLAS experiment. Today, the United States still ranks No. 1 in most science and engineering indicators, but recent figures from the National Science Foundation indicate that the U.S. lead is eroding. And it doesn't take a Ph.D. to figure out that when it comes to cutting-edge physics, all roads are currently leading to Europe.

Michio Kaku, a widely known author and theoretical physicist at the City College of New York, traces the reversal of fortunes back to the cancellation of the Superconducting Super Collider project in Texas.

"Let's be blunt about this: There could be a brain drain of some of our finest minds to Europe, because that's where the action is," Kaku said. "We had our chance, but Congress canceled our supercollider back in 1994. We're out of the picture. We can basically tag along after the Europeans, begging them for time on their machine — but really, the action is in Europe now."

Dutch physicist Jos Engelen, CERN's deputy director general and chief scientific officer, pretty much agrees with Kaku.

"People now talk of an inverse brain drain," he said. "That is, on these projects, our American colleagues have no difficulty finding other American colleagues who want to join us."

Engelen's boss, CERN Director General Robert Aymar, put it even more starkly during a news conference after Wednesday's startup: "Whatever happened, the competition was won by CERN."

The scientific spotlight's shift to Europe raises a dilemma for Yurkewicz and his wife, Katie, a physicist who works in CERN's communication office. For the sake of their 6-month-old son and their families back home, they'd love to move back to the United States when Adam's postdoctoral stint ends next year. But they both realize their job prospects are a lot better if they stay at CERN.

"Whether I'd want to stay ... I haven't decided on that yet," Adam Yurkewicz said a couple of months ago. "Right now, it looks like a big advantage to be here."

Commuters with computers

Not all of the 10,000-plus people involved in the LHC project are full-time residents like Yurkewicz. Most researchers spend just a few weeks at a time at CERN — checking in on their experiments (with graduate students in tow), then returning to their labs and classrooms back home.

"It's almost like commuting for those of us on the short term," said Karl Ecklund, a physics professor at the University of Buffalo who is part of the team behind the LHC's Compact Muon Solenoid detector, or CMS for short.


Another way that the LHC's researchers can be involved in the experiments without being there is to plug in through videoconferencing. Even before the final push to the collider's startup, it was difficult to reserve a spot for video linkups during the afternoons in CERN, which correspond with the morning's working hours in the United States.

Once the collider has been up and running for a while, some of the maintenance duties could be shifted thousands of miles away, thanks to high-speed network links that connect the control rooms at CERN with remote operations centers around the world.

"A lot of the shift work is just watching things. ... Shifting it to the U.S. is just a question of bandwidth," said Fermilab's Joel Butler, head of the US-CMS Research Program. "I don't imagine the're going to let you 'drive' the lab, but you can at least read the map and tell what's going on."

Nevertheless, virtual reality has its limits — particularly now, when the multibillion-dollar machine's kinks have to be ironed out. "There's nothing like being there," Ecklund said.

The next big thing
Is the Large Hadron Collider a model for big science projects to come, or will it turn out to be the last of the big-science dinosaurs? Nearly everyone involved in the project says that the expense and the complexity required for doing grand scientific experiments have become greater than any one country could manage alone.

"Each facility of this scale is going to exist in one place in the world," Butler said.

Video: The biggest physics experiment in history

So who decides how and where big science projects will be conducted? In the case of the Large Hadron Collider, CERN went ahead with its plan, and other nations gradually signed on. A slightly different model came into play for the ITER fusion project — which is being organized and funded by Europe's atomic energy agency and six other nations, including the United States.

The concept behind ITER goes back to the Reagan-Gorbachev summits of the 1980s, but it took years of political machinations to nail down the details. Finally, in 2005, the partners struck a compromise that put ITER's research reactor in France and another research center in Japan. ITER's structure calls upon each of the partners to provide hardware according to a complicated formula, leading up to the scheduled start of operations in 2016.

Aymar, a French physicist who headed up the ITER project before he took on CERN's top job, is intimately familiar with both approaches. He said CERN can take advantage of a huge head start in future international science projects, just because it's been doing it successfully for more than 50 years.

"To start from zero ... I don't recommend for any international body just to start," Aymar said. "It's very, very difficult, because you have to provide everything, with no background."

Long-term and short-term futures
That doesn't mean CERN has a lock on the next Big Bang Machine. The United States and other nations are also interested in at least a piece of the action. That includes the rising stars in science and technology, such as China and India. Just last year, Beijing hosted an exploratory meeting for designing the International Linear Collider, the particle-physics project regarded as the successor to the LHC.

The ILC won't be built until sometime in the next decade — if it's built at all. That depends on whether the LHC is successful, and whether governments ultimately decide that the ILC's estimated $6.7 billion cost (or whatever the full cost turns out to be) is worth it.

The amount of money and political will for doing grand physics projects is clearly limited, said physicist Barry Barish, director of the ILC's Global Design Effort. He estimated that the international community would be willing to fund a $5 billion to $10 billion international project every 10 to 20 years.

"Obviously, we can do one every one or two decades, and that's it, because of the cost," he said this year at a scientific conference. "So we have to do the right one."

Does cutting-edge physics really have to cost so much? Lawrence Krauss, a theoretical physicist at Case Western Reserve University, said many people assume that physicists get together and ask themselves, "How can we come up with something that costs the most?" But Krauss argued that the reality was exactly the opposite.

"If you want to do the challenge of fusion, if you want to understand the early universe or the fundamental structure of matter, there's just no other way. This is the least amount you can spend," Krauss said. "You just have to decide if it's worth it."

For Yurkewicz and thousands of other physicists, it's worth it — even if they have to journey to a foreign land. It's particularly worth it now, when the Big Bang Machine is starting up.

"The most exciting part of particle physics," he said, "is being in that control room and watching the data come in."

[troach]

http://cosmiclog.msnbc.msn.com/_news/2008/09/12/4351175-big-bang-sparks-big-reaction


Big bang sparks big reaction


12 sept 2008

This week's startup of Europe's Large Hadron Collider didn't generate a big bang or a black hole, but it did generate a big reaction from folks who followed our series on the "Big Bang Machine." More than 40,000 people voiced their opinion by clicking through our unscientific survey or by discussing the issues in online forums.

To my mind, the scariest thing that came up was not the discussion over whether or not the collider might create a cosmic catastrophe (the overwhelming scientific verdict is that it won't), but the mortal fear that the discussion sparked among kids around the world. For those young people - and not-so-young people as well - I have two words of advice, taken straight from "The Hitchhiker's Guide to the Galaxy":

DON'T PANIC!

Ask an expert if you can. Sign a petition if you wish. But don't give in to dark thoughts because some people are talking about microscopic black holes, strangelets or other high-energy hobgoblins. Remember, history is filled with other way-out doomsday scares ranging from Y2K meltdowns to alien invasions.

This week's startup went as smooth as silk at the CERN particle-physics center near Geneva, but that won't necessarily stop the doomsday talk. Over the next few weeks, the LHC will be building up power and starting collisions, while the legal issues surrounding high-energy physics will be debated in the courts - and that means the worries about the LHC will continue to come up in public forums.

In fact, there may always be a background buzz of subatomic scariness, just as some folks keep insisting that the Face on Mars (or Mermaid on Mars) is an alien artifact. But there are more serious things to worry about, ranging from the monster hurricane slamming the Gulf Coast to the chances of a killer asteroid heading our way (estimated background risk: 1 in 500,000 for any given year).

The online survey we conducted this week is by no means reflective of true public opinion, as we repeatedly remind people. I suspect that a lot of people don't know or don't care about the Large Hadron Collider. Nevertheless, the results indicate that a lot of people know enough not to panic: Just under 60 percent of the responses were clicks of enthusiastic support for the experiment. About 20 percent said they were worried about a cosmic catastrophe, and another 20 percent thought the device was a waste of money.

[troach]

http://cosmiclog.msnbc.msn.com/_news/2008/06/20/4350234-report-rules-out-subatomic-doomsday

Report rules out subatomic doomsday

20 jun 2008

Europe's CERN particle-physics lab has issued its long-awaited report on safety issues surrounding the Large Hadron Collider, the world's biggest and most expensive atom-smasher. Some have feared that when the collider reaches full power, sometime next year, it might create microscopic black holes or other exotic phenomena that could endanger Earth. The new report, like earlier safety studies, rules out the possibility of global danger.

Critics of the collider are pursuing a federal lawsuit challenging the safety claims - and they're likely to continue the doomsday debate even in the wake of this report.

The report's argument follows the basic line used in past reports: Even the most energetic collisions planned for the LHC are far less powerful than cosmic-ray collisions that have been going on for billions of years.

"Nature has already generated on Earth as many collisions as about a million LHC experiments – and the planet still exists," CERN said in its lay-language summary of the report. "Astronomers observe an enormous number of larger astronomical bodies throughout the universe, all of which are also struck by cosmic rays. The universe as a whole conducts more than 10 million million LHC-like experiments per second. The possibility of any dangerous consequences contradicts what astronomers see - stars and galaxies still exist."

The report also delves into the theoretical implications even if it turns out that microscopic black holes may hang around longer than most scientists think, and still ends up ruling out the catastrophic risk. In the stable-black-hole scenario, physicists do not expect the black holes to gobble up matter and grow to a monster size. Instead, they would interact - or not interact - with the particles they came across.

You'll want to start with CERN's summary document and then check out the full report. The report was reviewed by outside experts, and a separate report lays out what they had to say.

CERN discussed the safety report in a news release today, issued after this week's meeting of the CERN Council. Here's the text:

"At its 147th meeting in Geneva today, the CERN Council heard news on progress towards start-up of the laboratory's flagship research facility, the Large Hadron Collider (LHC). Commissioning of the 27-kilometre LHC began in January 2007 when the first cooldown of one of the machine's eight sectors began. Today, five sectors are at or close to their operating temperature of 1.9 degrees above absolute zero and the remaining three are approaching that temperature. Once all sectors are cold, electrical testing will be concluded in readiness for first beams, currently scheduled for August.

"'The accelerator, detectors and computing are all on course,' said CERN Director General Robert Aymar, 'and we are looking forward to the earliest possible LHC start-up.'

"When the LHC starts up this summer, its proton beams will collide at higher energies than have ever been produced in a particle accelerator. The collision energy of the LHC, however, is modest compared to the energies of the cosmic ray protons that have been striking the Earth's atmosphere for billions of years.

"'The LHC is the highest-energy particle accelerator on Earth,' said Dr. Aymar, 'but the universe has far more powerful ones. The LHC will enable us to study in detail under laboratory conditions what nature is doing already.'

"The LHC is subject to numerous audits covering all aspects of safety and environmental impact. The latest of these, addressing the question of whether there is any danger related to the production of new particles at the LHC, was presented to Council at this meeting. Updating a 2003 paper, this new report incorporates recent experimental and observational data.

"It confirms and strengthens the conclusion of the 2003 report that there is no cause for concern. The report was prepared by a group of scientists at CERN, the University of California, Santa Barbara, and the Institute for Nuclear Research of the Russian Academy of Sciences.

"'With this report, the Laboratory has fulfilled every safety and environmental evaluation necessary to ensure safe operation of this exciting new research facility,' said Dr. Aymar.

"The new report has been reviewed by the Scientific Policy Committee (SPC), a body that advises the CERN Council on scientific matters. A panel of five independent scientists, including one Nobel laureate, reviewed and endorsed the authors' approach of basing their arguments on irrefutable observational evidence to conclude that new particles produced at the LHC will pose no danger. The panel presented its conclusions to this week's meeting of the full 20 members of the SPC, who unanimously approved this conclusion.

"'It was right for the Director General of CERN to commission a formal assessment of safety issues, examining even the most unlikely of scenarios,' said Council President Torsten Åkesson. 'This new report concludes that there is no basis for any concern, a position endorsed by the 20 independent experts who form the SPC.'

The news release confirms that researchers will start sending beams through the LHC in August rather than July - but the startup procedure is expected to take months, with actual collisions coming later, and collisions at full power coming later still.