Cutting Edge

A 32-year-old nuclear physicist, part of the Large Hadron Collider project on the Swiss-French border, has been arrested by French police on suspicion of involvement with al-Qaeda.

According to The Independent, the arrest was made after anti-terrorist police had followed his movements for more than a year. Le Figaro newspaper suggested that the man's name had originally come to light in connection with the "Afghan network" of terrorist groups based in Europe.

(Credit: CC Ethan Hein/Flickr)

Of Algerian origin, he was arrested together with his brother, who was not working on the Collider.

Sources told The Independent that the scientist was not thought to be threatening the Collider itself, but rather was helping terrorists choose nuclear targets for attack.

The French Ministry of the Interior told Le Figaro that, having seized the man's two computers, three hard disks, and several USB keys, it believed the threat was serious. A Ministry spokesman said, "Our investigation showed without doubt that there were targets in France and elsewhere and indicated that we have perhaps avoided the worst."

CERN reassured the Independent that the suspect was not working on any of the major elements of the Collider, nor did he have access to the tunnel in which the Big Bang experiment is to be carried out. The CERN representative added, "None of our research has potential for military application, and all our results are published openly in the public domain."

The Collider is due to for a restart in November. One can only hope it's a safe one.

The world's largest particle accelerator is on course for a November restart. Six out of eight superconducting sectors are down to working cryogenic temperatures, according to CERN, the European Organization for Nuclear Research.

James Gillies, head of communications for CERN, told ZDNet UK on Monday that the Large Hadron Collider (LHC) would probably be ready to collide beams of particles by mid-November.

"Things are going well," said Gillies. "We hesitate to say 'hurray' just yet, but things are going smoothly."

Gillies said CERN plans to restart the giant experiment in incremental stages.

Read more of "LHC on course for November restart" at ZDNet UK.

A silicon detector being installed in the Large Hadron Collider in December 2007.

(Credit: Michael Hoch/CERN)

After a year of setbacks, CERN plans to restart its Large Hadron Collider in November at a tempo that won't overtax the machinery behind the giant particle physics experiment.

The collider, located deep underground on the border between France and Switzerland, will start out running at an energy level of 3.5 trillion electron volts (TeV) per beam, about half the energy that CERN expects eventually. The physicists will inject and capture high-energy beams running in each direction on the circular collider's 17-mile circumference, log data over a number of weeks, and simply get themselves up to speed on the systems.

"We've selected 3.5 TeV to start," Rolf Heuer, director general of CERN, said in a statement Thursday, "because it allows the LHC operators to gain experience of running the machine safely while opening up a new discovery region for the experiments."

The experiment that CERN--the European Organization for Nuclear Research--has in mind are nothing short of grandly ambitious. The collision of subatomic particles in the Large Hadron Collider could offer insights into the very earliest workings of the universe.

And the machinery is immensely complex, with 10,000 high-current superconducting electrical connections. The collider has cost $9 billion and taken 15 years to get to where it is now, according to an article earlier this week in The New York Times.

It was one of those electrical connections that misfired shortly after the collider was turned on for the first time in September 2008, causing CERN to curtail operations while it moved on to investigate and repair the the initial problems--and then subsequent troubles--and to plan its next steps. Tests of the collider's copper stabilizer wrapped up satisfactorily last week, meaning "no more repairs are necessary for safe running this year and next," CERN announced Thursday.

"The LHC is a much better understood machine than it was a year ago," Heuer said. "We can look forward with confidence and excitement to a good run through the winter and into next year."

After a significant data sample has been collected running the LHC at 3.5 TeV per beam, CERN said it would move toward 5 TeV and, at the end of 2010, would introduce lead ions for the first time.

Then it will be time to shut down the collider once again as CERN gets ready to get the machinery running at 7 TeV. ("1 TeV," says CERN's glossary, "is about the energy of motion of a flying mosquito. What makes the LHC so extraordinary is that it squeezes energy into a space about a million million times smaller than a mosquito.")

The latest delays to the restart of the Large Hadron Collider are likely to have been caused by a faulty hose, according to CERN, the European Organization for Nuclear Research.

Liquid helium leaks in the world's largest particle accelerator were probably caused by a problem with a flexible hose in the liquid helium transport circuits, the organization said an article in its official bulletin, published on Friday.

Click image for gallery on the Large Hadron Collider.

(Credit: Maximilien Brice for CERN)

The hose vented helium into the vacuum insulation of the Large Hadron Collider (LHC), CERN officials suspect.

CERN has revised the restart date of the LHC several times since the experiment was put out of action in September by an electrical fault. According to the latest estimates, the particle acceleration experiment is unlikely to restart before mid-November.

The vacuum leaks occurred in sectors 8-1 and 2-3 in July. At the time, CERN said that the sectors would have to be warmed from 80 Kelvin (-315.67 degrees Fahrenheit) to room temperature to effect repairs.

On Monday, the organization changed that plan, saying the vacuum subsectors at the end of the sectors will be warmed to room temperature to locate the leaks and repair them. The rest of those sectors will "float" in temperature from 80K.

Both leaks happened at the place where the final magnet of those sectors, which is known as Q7, joins the electrical feedbox, known as the DFBA.

The LHC experiment is designed to enable research into fundamental questions about nuclear particles, such as the existence of dark matter.

Tom Espiner of ZDNet UK reported from London.

The restart of the Large Hadron Collider has been pushed back even further, following the discovery of vacuum leaks in two sectors of the experiment.

The world's largest particle collider is now unlikely to restart before mid-November, according to CERN, the European Organization for Nuclear Research.

The project had been expected to start again in October.

The collider's experiments are designed to answer fundamental questions about the nature of matter.

(Credit: CERN)

To repair the leaks, which are from the helium circuit into the insulating vacuum, sectors 8-1 and 2-3 will have to be warmed from 80K to room temperature. Adjacent sub-sectors will act as "floats," while the remainder of the surrounding sectors will be kept at 80K, CERN said in a statement. The repair work will not have an impact on the vacuum in the beam pipe.

The LHC experiment, which is designed to answer fundamental questions about the nature of matter, had to be halted nine days after it became fully operational last September, due to a leak of liquid helium. To be super-conductive, the experiment is cooled using liquid helium.

CERN has pushed back the restart a number of times, as repair work has continued. To begin with, scientists said the LHC experiment would restart in April 2009.

In May, CERN told ZDNet UK that the restarted experiment could run through the winter to make up some of the lost time. Normally, running the experiments through the alpine winter is prohibitively expensive, due to high electricity costs. However, as the experiment has not been running since last September, CERN would have the budget to cover energy costs over the winter.

Tom Espiner of ZDNet UK reported from London.

The grid that will process data from the Large Hadron Collider has undergone stress-testing, as CERN and other groups try to gauge its limits.

The tests, called Scale Testing for the Experiment Program '09, threw huge amounts of data around the distributed computing project, which uses dedicated optical-fiber networks to distribute data from CERN (European Organization for Nuclear Research) to 11 main computer centers in Europe, Asia, and North America.

From these centers, data is dispatched to over 140 centers in 33 countries around the globe, where the LHC data is managed and processed. The recent grid tests, which lasted for two weeks, were completed before the beginning of July.

Click image for gallery on the Large Hadron Collider.

(Credit: Maximilien Brice for CERN)

LHC computing-grid project leader Ian Bird said Friday that CERN had tried to break the grid but had not succeeded.

"People were trying to break the system by seeing how much data we could push through it, but we didn't (break it)," Bird told ZDNet UK. "The test was successful."

Data from all the experiments running at CERN--including analyses from the Atlas particle accelerator, which is linked to the LHC--were processed through the grid, according to Bird. While the amount of data expected from the LHC will be in the area of 1.3GB per second, the grid systems were bombarded with 4GB per second. "The data volume got to a much larger scale than is needed," Bird said.

CERN plans to restart the LHC in October, following an incident last September that halted the experiment. A fault, caused by imperfect welding, led to a leak of liquid helium that caused damage when it heated and expanded.

At present, the LHC itself is not generating any data, as no experiments are being conducted, Bird said. However, the experiment was gathering data from cosmic rays hitting the experiment until testing of the machine stopped the collection. This data is due to be collected again "in a few weeks," Bird added.

Bird did not rule out a further major test of the computing grid before the LHC's October restart, as some parts of the grid had been offline during the testing due to scheduled downtime.

Tom Espiner of ZDNet UK reported from London.

The flagship particle accelerator at the European Organisation for Nuclear Research is to be restarted in October, as opposed to September.

Click image for gallery on the Large Hadron Collider.

(Credit: Maximilien Brice for CERN)

The Large Hadron Collider has been offline since an incident on September 19, when an equipment failure caused extensive damage. James Gillies, CERN's head of communications, said on Monday that an internal schedule set in February to restart the experiment has been pushed back by two or three weeks, but that the restart would still commence in the fall.

"The situation is a retreat from February," Gillies told ZDNet UK. "We had aimed for the end of September, but we're now looking at somewhere in October."

CERN has revised its LHC restart date a number of times. An original October 2008 estimate of an April 2009 restart was pushed back to the end of the summer, and was then revised to September.

The experiment, which is designed to improve scientific understanding of the nature of matter, had to be halted nine days after it was fully powered up, after an electrical malfunction caused a leak of liquid helium.

In May, details emerged that the malfunction had been caused by a faulty splice between two of the busbars that carry the superconducting cable in the LHC. Gillies said that the problem had not been in the design, but rather in the implementation of the electrical circuits for the quench system.

"It was a quality control flaw," Gillies said. "Most of the splices were done well, but a few of the solder joints were not perfectly carried out. We know there were a number of faulty splices in the machine. We've repaired a few, and we'll be repairing more."

CERN has developed noninvasive ways of testing the electrical circuits in some of the systems, which have remained cooled to 80 Kelvin (negative 315.67 degrees Fahrenheit), Gillies said. In circuits where faults have been found, Gillies said the surrounding sectors will be warmed to room temperature, and then the circuits will be repaired and tested again.

Gillies said CERN won't be able to give an exact restart date until August, when testing is completed. CERN has not decided whether to run the experiment at 4 teraelecton volts or at 5TeV. The world's most powerful particle accelerator, the Tevatron at Fermilab near Chicago, runs at 1TeV.

Tom Espiner of ZDNet UK reported from London.

The final replacement magnet for the Large Hadron Collider has been lowered into the giant particle accelerator's tunnel.

The European Organization for Nuclear Research (CERN) announced on Thursday the completion of the LHC's above-ground repair work. Work is still going on below ground to connect the 53 reinstalled magnets, which are used in the scientific project to guide particles around a 17-mile tunnel under the Alps. The LHC fires two high-speed particles streams around the tunnel in opposite directions, smashing them together at certain points in order to learn more about scientific mysteries such as the nature of matter.

This photo from last year shows two of the most severely broken interconnects, which were between the magnets in LHC sectors three and four.

(Credit: CERN)

The LHC went offline in September 2008--just days after the LHC was turned on for the first time.

The problem started when a faulty electrical connection between two of its magnets caused a malfunction in the cooling system that keeps the machine below -271 degrees C. That malfunction subsequently led to a liquid helium leak, resulting in a need for widespread repairs. By CERN's latest reckoning, the system will be turned on again in late September of this year.

"This is an important milestone in the repair process," Steve Myers, CERN's director for accelerators and technology, said in a statement. "It gets us close to where we were before the incident, and allows us to concentrate our efforts on installing the systems that will ensure a similar incident won't happen again."

The magnet that was lowered underground on Thursday was a quadrupole: one of the magnets that focuses the particle stream, rather than one of the dipole magnets that keep the stream on course.

Click image for a 2008 gallery on the LHC.

(Credit: Maximilien Brice for CERN)

Of the 53 magnets that were affected by the malfunction, 16 were refurbished and put back into the tunnel, while 37 were replaced by spares. The replaced magnets will themselves be refurbished to provide spares for the future.

Apart from the repair itself, the LHC is also gaining systems to monitor its functioning, in order to avoid a repeat of the September incident. Extra pressure valves are also being installed to make any helium releases less disastrous to the project.

David Meyer of ZDNet UK reported from London.

Click image for gallery on the Large Hadron Collider.

(Credit: Maximilien Brice for CERN)

The Large Hadron Collider could be restarted at the end of September--a year after the world's largest particle accelerator was knocked off line by an electrical malfunction.

LHC operations were suspended last September after a transformer malfunction in its cooling system allowed a helium leak--just nine days after the controversial project became operational. An investigation concluded that the malfunction was caused by a faulty electrical connection between two of the accelerator's magnets.

As a result, the 53 magnets used to accelerate sub-atomic particles around the machine's 17-mile underground tunnel had to be cleaned or repaired. At the time, the repair costs for the $5 billion LHC were expected to top $16 million.

The European Organization for Nuclear Research, or CERN, the organization that built the LHC, announced Monday that it expects the first beams to begin in September, with the first collisions expected by late October.

The delay is the latest in a string of restart dates CERN has announced. CERN had originally expected to have the LHC back online at the beginning of April, following CERN's annual maintenance period. But that target was revised last November to June. Later that month, CERN's head of communications, James Gillies, told ZDNet UK that the new plan was to restart the LHC in late summer.

"The schedule we have now is without a doubt the best for the LHC and for the physicists waiting for data," CERN Director General Rolf Heuer said in a statement. "It is cautious, ensuring that all the necessary work is done on the LHC before we start-up, yet it allows physics research to begin this year."

The LHC, located along the French-Swiss border, is designed to smash beams of protons into each other, test fundamental physics theories, and help understand the nature of matter.