World's biggest atom smasher sets first record

After a year's delay, the Large Hadron Collider near Geneva became the world's highest-energy particle accelerator on November 30, revving up each of its twin proton beams to energies of 1.18 trillion electron volts. That smashes the record of 0.98 trillion eV held since 2001 by the Fermi National Accelerator Laboratory's Tevatron in Batavia, Ill.

However, the researchers have yet to collide the beams at this record-breaking energy. So far, the highest collision energies at the LHC have only been 450 million eV.

The collision energies that the LHC can attain are critical for investigating the fundamental forces and particles in nature. That's because the more powerful the accelerator, the heavier the particles it can produce. For instance, researchers hope the LHC may find the elusive Higgs boson, a proposed, extremely massive subatomic particle that, if found, would explain why elementary particles have the particular mass they do. 

The Large Hadron Collider shut down for a year beginning in September 2008 — soon after its first collisions — when a faulty electrical connection between two magnets led to a leak of helium gas in a section of the accelerator. 

Engineers restarted the collider on November 20, injecting the first beams since 2008 into the accelerator. The first low-energy collisions since the breakdown took place November 23 and were recorded by the accelerator's four major detectors. Scientists hope to collide each beam at energies of 3.5 trillion eV by March 2010. The LHC won't operate at its highest possible energy, corresponding to 7 trillion eV per beam, until 2011, said a spokeswoman from CERN, the European Organization for Nuclear Research, which hosts the LHC.

At the time of the electrical mishap last year, about 10,000 amps of current were flowing through the collider's magnets. On November 30, when the collider's proton beams achieved their record energy, only 2,000 amps flowed through the magnets, the spokeswoman said. A full 10,000 amps won't circulate until early next year.

In addition to increasing the current, scientists are also working to collide the beams at higher intensities. So far, each colliding beam has contained only about 5 billion protons, but researchers ultimately want to achieve collisions with 110 billion protons per beam by early in 2010.

[SOURCE: SCIENCE NEWS]

Large Hadron Collider progress delights researchers

Researchers working on the Large Hadron Collider (LHC) say they are delighted with the progress made since the machine restarted on Friday.

One official said the collider had done more in a few hours than it did in five days of operations last year.

The LHC is being used to smash together beams of protons in a bid to shed light on the nature of the Universe.

Housed in a 27km-long circular tunnel under the Franco-Swiss border, it is the world's largest machine.

During the experiment, scientists will search for signs of the Higgs boson, a sub-atomic particle that is crucial to our current understanding of physics. Although it is predicted to exist,
scientists have never found it.

The machine was heavily damaged when an electrical fault caused a tonne of liquid helium to leak into the tunnel just nine days after it was first launched in September last year.

During 14 months of repairs dozens of giant superconducting magnets that accelerate particles at the speed of light had to be replaced.

Operated by the European Organization for Nuclear Research (Cern), the LHC will create similar conditions to those which were present moments after the Big Bang.

"We are further advanced now than where we were after five days of experiment last year," said Cern's director of accelerators Steve Myers.

He added that the extra year had allowed researchers to upgrade instrumentation and computer software.

"It's all been pretty positive so far," said James Gillies, director of communications for Cern. "Now, [the team] is knuckling down to the hard work."

He added: "We're not expecting any major milestones to be reached over the next few days."

Operations team members spent Saturday injecting protons into the LHC's 27km-long "ring", attempting to improve the lifetime of the beams.

"Right now we've got a beam lifetime of half an hour, which is pretty good for where we are. But ultimately, we want to keep a beam in the machine for 10-12 hours. There's a lot of detailed, nitty-gritty work in order to get there," said Dr Gillies.

Engineers had discussed the possibility of attempting to increase the collider's energy to a record-breaking level of 1.2 trillion electron volts this weekend.

Only the Tevatron particle accelerator in Chicago, US, has so far approached this energy, operating at just under one trillion electron volts.

However, this plan now looks unlikely. Instead, engineers will probably concentrate on preparing the machine for its first low-energy collisions, scheduled to happen in the next 10-15 days.

Progress on restarting the machine went more quickly than expected on Friday. It was not anticipated that engineers would try to circulate a proton beam until 0600 on Saturday at the earliest.

Two stable proton beams had already been circulated in opposite directions around the machine by midnight (GMT) on Friday.

Engineers first circulated a beam all the way around the LHC on 10 September 2008.

[SOURCE: BBC]

Interview with Prof. Rolf-Dieter Heuer, Director-General of CERN

Prof. Rolf-Dieter Heuer - Director-General of CERN

Tomorrow Today (DW-TV's Science Magazine) interviewed Prof. Rolf-Dieter Heuer, Director-General of CERN. Below is an excerpt from the Interview.


DW-TV: The 19th of September in the last year was a black day at CERN. How dramatic is actually the break.

Rolf-Dieter Heuer: The break is dramatic in terms of time because it took a bit more than one year to do everything. But it's not dramatic in the sense of spirit. The spirit is very high. But what we had to do was, first of all we had to repair the damage, secondly we had to measure all the other connections in order to be sure that something like this could be avoided again, and thirdly we had to install a lot of new electronics, cabling, et cetera. And all this together takes more than one year, but then we are pretty sure to start up safely.

DW-TV: Which is a long time: one year. Since also physicists in America, in Chicago, are also searching for the Higgs boson. Are you afraid they might outpace you?

Rolf-Dieter Heuer: No, I'm not afraid of this, because if I look only on science, I don't care where things are found first, and secondly, even if they find something, they only can find indications, and only LHD can tell you if there's really something, and thirdly, when we switch on in November, after one year we will have the same discovery potential or even better than our friendly competitors in the US.

DW-TV: But you're not only a scientist, you're also the director-general of CERN. So how important is it to find the Higgs boson if there is a Higgs boson actually here at CERN?

Rolf-Dieter Heuer: I think it would be very important, it would be a huge stimulus for CERN, that's clear. But it would be even more important of the progress of particle physics and the progress of research, fundamental research in general. So it would be very important.

DW-TV: But wouldn't it be also maybe kind of boring? Because if you find a Higgs boson, all you do is confirm the standard model of elementary particles, and so to say, you'd have no surprise.

Rolf-Dieter Heuer: I'm pretty sure that the surprise is outside the standard model, you are right. We would confirm the standard model, but the standard model can only be a model which is only valid for our energy region. If you go beyond our energy, much beyond our energy range, then there must be another model which incorporates the standard model but which goes further, like, for example, supersymmetry.

DW-TV: So physics as we think today is still correct whether we find the Higgs or whether we don't find it?

Rolf-Dieter Heuer: Yes, of course, because we have measured it, and so it's correct. And compare it to Newton's mechanics, do you feel anything from the relativistic mechanics?

DW-TV: No, not very much.

Rolf-Dieter Heuer: Because you are not in that velocity range. You can compare the standard model to a range within a certain energy limit, and then the new model beyond that, like the different between Newton and Einstein's.

DW-TV: CERN and the new collider is not only a big hit with physicists, but also with authors and film directors ... even scientist argued that the LHC might trigger a dangerous black hole, a gravitational field, so strong nothing can escape.

Rolf-Dieter Heuer: I would not be happy if we would find it in only one of the detectors, because I always need confirmation -- I need it in both detectors. I need confirmation. But these black holes have nothing to do with the black holes which you have in astronomy, in the universe. These black holes would be micro black holes, which would be produced at the LHC and then immediately decay again. This is according to all the existing theories, including the theories from Stephen Hawking.

Read the whole Interview

(Interview Ingolf Baur)

LHC STARTS IN NOVEMBER

When launched to great fanfare nearly a year ago, some feared the Large Hadron Collider would create a black hole that would suck in the world. It turns out the Hadron may be the black hole.

The world's largest scientific machine has cost $10 billion, has worked only nine days and has yet to smash an atom. The unique equipment in a 17-mile (27-kilometer) circular tunnel with cathedral-sized detectors deep beneath the Swiss-French border has been assembled by specialists in many countries, with 8,970 physicists eagerly awaiting the startup.

But despite the expense, thousands of physicists around the world, many of whom hope to conduct experiments here, insist that it will work and that it is crucial to mankind'sunderstanding of the universe.

The European Organization for Nuclear Research, known as CERN, said Friday it would restart the collider in November at half power under pressure from scientists eager to conduct experiments to unlock secrets of the universe.

But spokesman James Gillies told The Associated Press they would have to shut down yet again next year to finish repairs so that the Large Hadron Collider can operate at full energy of 7 trillion electron volts — seven times higher than any other machine in the world.

CERN has been working since late last year to repair the damage caused by a faulty electrical joint. The breakdown occurred nine days after the spectacular start up of the $10 billion machine last Sept. 10 when beams of subatomic particles were sent around the accelerator in opposite directions.

Fifty-three massive electrical magnets had to be cleaned and repaired after the failure. Tons of supercold liquid helium spilled out of the system, and a sooty residue had to be cleared from the tubes that are meant to be pristine, holding a vacuum in which subatomic particles can whiz around the tunnel at near the speed of light at temperatures colder than outer space.

Michio Kaku, a physics professor at City University of New York who is an outspoken critic of waste in big science projects, defends the CERN collider as a crucial investment.

CERN expects repairs and additional safety systems to cost about 40 million Swiss francs ($37 million) over the course of several years, covered by the 20-nation organization's budget.

The collider emerged as the world's largest after the U.S. canceled the Superconducting Super Collider being built in Texas in 1993. Congress pulled the plug after costs soared, and questions were raised about the value of the science it could produce.

Gillies says all 20 of CERN's member nations have remained supportive and that four other countries — Cyprus, Israel, Serbia and Turkey — have asked to join. A fifth country — Slovenia — has expressed interest.

Japan, India, Russia and the U.S. are observer countries that have made sizable contributions to the CERN project.

CERN is now aiming to restart the machine in November with beams of subatomic particles initially running at 3.5 trillion electron volts, or TeV. That's only half the level the machine was designed for, but it's still 3 1/2 times higher than the second most powerful accelerator, the Tevatron at Fermilab outside Chicago. During last year's brief startup phase, the CERN collider only operated at half the Fermilab level.

Even as the machine is being calibrated this winter, scientists will be able to conduct experiments, collecting data on the collisions of protons and lead ions in the accelerator.

They hope the higher energy will enable them to see particles so far undetected, such as the elusive Higgs boson, which in theory gives mass to other particles — and objects and creatures — in the universe.

Physicists have used smaller, room-temperature colliders for decades to study the atom. They once thought protons and neutrons were the smallest components of the atom's nucleus, but the colliders showed that they are made of quarks and gluons and that there are other forces and particles. And they still have other questions about antimatter, dark matter and particle mass they want to answer with CERN's new collider.

They hope the fragments that come off the collisions will show on a tiny scale what happened one-trillionth of a second after the so-called Big Bang, which many scientists theorize was the massive explosion that formed the universe. The theory holds that the universe was rapidly cooling at that stage and matter was changing quickly.

Some skeptics have expressed fears the high-energy collision of protons could 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.

CERN and leading physicists dismiss the fears and maintain the project is safe.

The collider's teething problems are typical of complicated accelerators, but it has been especially frustrating to physicists from around the world, who already have been waiting for years to conduct their experiments on the machine.

They decided some of the splices need to be repaired before the collider goes to full power, but that they can operate safely up to 5 TeV without further repairs now.

That has been set as the highest energy for the collider before its next shutdown for maintenance, probably in November 2010. Then the further repairs will be made so that the energy level can be ramped up.

Rolf Heuer, who has taken over as CERN's director-general since the failure, said the collider has been studied very carefully and is much better understood than a year ago.

"We can look forward with confidence and excitement to a good run through the winter and into next year," Heuer said.

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Read About CERN

LHC TO BE REOPENED THIS YEAR

On 28 November the first replacement magnet for sector 3-4 was about to be lowered into the LHC tunnel.

The first replacement magnet for Sector 3-4 underwent its final preparations before being lowered into the tunnel on 28 November. This is a good indication of the progress being made on the repairs to the sector damaged on 19 September. Around a hundred CERN personnel and external contractors are engaged in the repair work and tests. By the time the Laboratory closes for the Christmas break, all the magnets needing to be repaired or simply needing to be cleaned (around fifty at most) will have been brought to the surface.

The teams are conducting tests to ensure that such an incident does not reoccur. Almost the entire machine has now been tested, with new tests having been developed and additional instrumentation being deployed.

The schedule for the LHC re-start in 2009 is being drawn up and will be announced during the Council’s December Session.

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The LARGE HADRON COLLIDER

The Large Hadron Collider (LHC) is the world's largest and highest-energy particle accelerator complex, intended to collide opposing beams of protons (one of several types of hadrons) with very high kinetic energy. Its main purpose is to explore the validity and limitations of the Standard Model, the current theoretical picture for particle physics.

It is theorized that the collider will confirm the existence of the Higgs boson. This would supply a crucial missing link in the Standard Model and explain how other elementary particles acquire properties such as mass.

The LHC was built by the European Organization for Nuclear Research (CERN), and lies underneath the Franco-Swiss border between the Jura Mountains and the Alps near Geneva, Switzerland.

It is funded by and built in collaboration with over eight thousand physicists from over eighty-five countries as well as hundreds of universities and laboratories.

The LHC is operational and is presently in the process of being prepared for collisions. The first beams were circulated through the collider on 10 September 2008, and the first high-energy collisions are expected to take place after 6-8 weeks.

The collider is contained in a circular tunnel, with a circumference of 27 kilometres (17 mi), at a depth ranging from 50 to 175 metres underground. The 3.8 m wide concrete-lined tunnel, constructed between 1983 and 1988, was formerly used to house the Large Electron-Positron Collider.

Six detectors have been constructed at the LHC, located underground in large caverns excavated at the LHC's intersection points. Two of them, the ATLAS experiment and the Compact Muon Solenoid (CMS), are large, general purpose particle detectors.

When in operation, about seven thousand scientists from eighty countries will have access to the LHC. It is theorized that the collider will produce the elusive Higgs boson, the last unobserved particle among those predicted by the Standard Model.

The verification of the existence of the Higgs boson would shed light on the mechanism of electroweak symmetry breaking, through which the particles of the Standard Model are thought to acquire their mass. In addition to the Higgs boson, new particles predicted by possible extensions of the Standard Model might be produced at the LHC.

More generally, physicists hope that the LHC will enhance their ability to answer the following questions:

1. Is the Higgs mechanism for generating elementary particle masses in the Standard Model indeed realised in nature?

If so, how many Higgs bosons are there, and what are their masses?

2. Are electromagnetism, the strong nuclear force and the weak nuclear force just different manifestations of a single unified force, as predicted by various Grand Unification Theories?

3. Why is gravity so many orders of magnitude weaker than the other three fundamental forces?

4. Is Supersymmetry realised in nature, implying that the known Standard Model particles have supersymmetric partners?

5. Will the more precise measurements of the masses and decays of the quarks continue to be mutually consistent within the Standard Model?

6. Why are there apparent violations of the symmetry between matter and antimatter?

7. What is the nature of dark matter and dark energy?

8. Are there extra dimensions, as predicted by various models inspired by string theory, and can we detect them?

Of the possible discoveries the LHC might make, only the discovery of the Higgs particle is relatively uncontroversial, but even this is not considered a certainty.

The total cost of the project is expected to be €3.2–6.4 billion.

The construction of LHC was approved in 1995 with a budget of 2.6 billion Swiss francs (€1.6 billion), with another 210 million francs (€140 million) towards the cost of the experiments. However, cost over-runs, estimated in a major review in 2001 at around 480 million francs (€300 million) for the accelerator, and 50 million francs (€30 million) for the experiments, along with a reduction in CERN's budget, pushed the completion date from 2005 to April 2007.

Once the supercollider is up and running, CERN scientists estimate that if the Standard Model is correct, a Higgs boson may be produced every few hours. At this rate, it may take up to three years to collect enough statistics unambiguously to discover the Higgs boson.

Although there have been questions concerning the safety of the planned experiments in the media and even through the courts, the consensus in the scientific community is that there is no basis for any conceivable threat from the LHC particle collisions.

A primary concern, the appearance of micro black holes, has been dismissed due to the improbability of their production and, even if produced, their infinitesimal size and instantaneous decay.

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