Results matching “lhc”

Physics Today: Updated: 2:38PM EST and 4:40PM EST: Scientists at the Large Hadron Collider (LHC), announced that they have sent a particle beam around the 27-kilometer collider.

"It’s great to see beam circulating in the LHC again," said CERN director general Rolf Heuer. "We’ve still got some way to go before physics can begin, but with this milestone we’re well on the way."

The LHC circulated its first beams on 10 September 2008, but suffered a serious malfunction nine days later. It has taken over a year repairing and consolidating the machine to ensure that such an incident cannot happen again.

"The LHC is a far better understood machine than it was a year ago," said CERN’s Director for Accelerators, Steve Myers. "We’ve learned from our experience, and engineered the technology that allows us to move on. That’s how progress is made."

The next important milestone will be low-energy collisions at 450 GeV, expected in about a week from now. Ramping the beams to high energy will follow in preparation for collisions at 7 TeV (3.5 TeV per beam) next year.

Recent coverage of the LHC by Physics Today can be found here.

Related news stories
Scientists at Cern hold their breath as they prepare to fire up the LHC The Guardian

Nature News: Last week, US particle physicists staked their claim in a daring new venture to develop the next generation of accelerators by proposing the world's first muon collider.

The collider could overtake two more-mature concepts, each of which plan to smash together electrons and positrons that have been accelerated through long, straight tunnels.

But some physicists at the Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois, are concerned about the expense and feasibility of the linear colliders, and question whether they would push the boundaries of physics beyond what the Large Hadron Collider is expected to achieve.

They are now trying to rally enthusiasm for a collider that smashes muons, a particle that is about 200 times more massive than the electron.

Related Link
Next-generation atom smashers: Smaller, cheaper and super powerful Wired.com

Physics Today: Tests on parts of the Large Hadron Collider over the weekend were fairly successful, suggest CERN documents.

Particles up to 450 GeV were injected into four sectors of the storage ring (sector 23, 78, 67, and 56).

For the first time—at 8:00pm local time on Saturday—the Compact Muon Solenoid (CMS) detector observed beam "splash" in the LHC, a major milestone for the experiment (see yellow indicators in image below).

These injection tests are the final phase before the main test on 20 November in which particles will traverse across the entire ring. Actual collisions between two opposing beams should occur at roughly the same date.

Over a 24-hour period on Monday, the sectors will be checked for radiation. Once the risk has been minimized, researchers and technicians will inspect the billion-dollar collider for any damage.

The LHC will run at reduced power for the next two years, in an attempt to minimize risk to the magnets.

Related News Picks
Beam particles re-enter the LHC
More LHC news picks

Related Links
The big bang at the LHC
The Guardian's science correspondent Ian Sample talks to Lynn Evans, project manager of Cern's Large Hadron Collider, who relives the moment he found out something had gone horribly wrong

The Register: A bird dropping a piece of bread onto outdoor machinery has been blamed for a technical fault at the Large Hadron Collider (LHC) this week which saw significant overheating in sections of the mighty particle-punisher's subterranean 27-km supercooled magnetic doughnut.

According to scientists at the project, had the LHC been operational—it is scheduled to recommence beaming later this month—the snag would have caused it to fail-safe and shut down automatically.

This would put the mighty machine out of action for a few days while it was restarted, but there would be no repeat of the catastrophic damage suffered last September.

The Observer: At first glance, the piece of metal in Steve Myers's hands could be taken for a harmonica or a pen. Only on closer inspection can you make out its true nature.

Myers, director of accelerators at the CERN particle physics laboratory outside Geneva, is clutching a section of copper piping from which a flat electrical cable is protruding.

It looks unremarkable. Yet a piece of cable like this one was responsible last year for the world's most expensive short circuit.

More than $50 million-worth of damage was done to the Large Hadron Collider (LHC), the most advanced particle accelerator ever built, a few days after its ceremonial opening.

It has taken Myers—and hundreds of other CERN scientists—more than a year to pinpoint the guilty piece of cable and repair the wreckage.

"It was a very small piece, but it did immense damage," he said. It remains to be seen whether Myers can fix CERN's tattered technological reputation in the process—when his team restart their great machine in a few weeks. "I am not a nervous person," said the 63-year-old Belfast-born engineer. "And that is probably just as well."

Related News Picks

Related Politics
Congress expresses concern over LHC failures
UK prepares for tough science funding environment

Related Physics Today articles
Mostly recovered, the LHC readies for restart October 2009
Mishap shuts down LHC until April November 2008
Multiple problems push LHC start to next spring September 2007

CERN: Ion and proton particles from CERN's Super Proton Synchrotron (SPS) were successfully injected into the Large Hadron Collider last weekend (23-25 October). It was the first time since September last year that particles were injected into the LHC.

The first ion beam entering point 2 of the LHC, just before the ALICE detector (23 October 2009. Image credit: CERN)

The particles did not travel along the whole circumference of the LHC because CERN is cautiously testing the new quench system—which will protect the magnets from similar damage to that experienced last year.

The LHC will operate at 450 GeV per beam when the machine becomes operational on 23 November, and eventually ramp up to 1.1 TeV per beam in December.

Using lower energies requires less current in the superconducting magnets and will get CERN some experience with the new safeguards before increasing the power output next year to 3.5 TeV per beam in February.

As Peter Woit at Columbia University points out on his blog.

This means that 2009 will not see physics collisions, but will perhaps see collisions at energies marginally higher than that of the Tevatron...

Meanwhile the Department of Energy is requesting extra funds for the Tevatron to keep the collider running through 2011.

Related News Picks

Related Physics Today articles
Mostly recovered, the LHC readies for restart October 2009
Mishap shuts down LHC until April November 2008
Multiple problems push LHC start to next spring September 2007

Article modified on 11/09/2009 to provide correct attribution of quote to Peter Woit.

Various: In a talk entitled Higgs, dark matter and supersymmetry, what the Large Hadron Collider will tell us, given to science writers attending the Council for the Advancement of Science Writing’s annual symposium, Nobel laureate Steven Weinberg of the University of Texas at Austin gave his opinion of what the LHC will discover.

The LHC will eventually attain sufficient energy to produce the Higgs boson, he says, but evidence of supersymmetry is a much more speculative possibility.

"If the Congress had not had the imbecility to cancel the Superconducting Super Collider [in 1993], it would have been discovered long ago here in Texas," says Weinberg in comments reported by Tom Siegfried of Science News.

"Many of us are terrified that the LHC will discover a Higgs particle and nothing more," Weinberg said. That would just confirm the standard model, which everybody believes already. It would not point the way to further progress in solving a deeper problem that physics faces—how to add gravity to the unified theory of the other forces.

Peter Woit of "Not Even Wrong" says that what he found interesting about Weinberg’s talk was that, "whatever Weinberg’s views on more speculative theories in physics such as extra dimensions or string theory landscape, he decided not to mention these at all in his talk."

"As a result, both questioners wanted to ask Weinberg about string theory, which he hadn’t talked about, not about the solid science he did talk about," says Woit.

String theory or superstring theory, is one of the candidates for unifying all the forces in the universe into one theory.

If the LHC creates new particles generated by supersymmetry, then clues to what makes up the bulk of dark matter in the universe would be found, which may give some tangible evidence to whether string theory is correct.

But string theory to this point has not produced a cohesive and clear guide to testing its fit with all the observable features of physical existence. Weinberg said:

"It’s developed mathematically, but not to the point where there is any one theory, or to the point that even if we had one theory we would know how to do calculations to predict things like the mass of the electron, or the masses of the quarks. So, I would say, although there has been theoretical progress... I find it disappointing. One of the hopes would be that the LHC would provide a clue to something we’re missing in superstring theory and I think that supersymmetry is the most likely place to look."

"One of the troubles with superstring theory is that although in a sense the theorists think there is only one theory, there are an infinite number of approximate solutions of it and we don’t know which one corresponds to our world. But at least in a large variety of the solutions of superstring theory there is supersymmetry visible at low energies, and if we see supersymmetry at low energies, superstring theorists may be able to derive from it some kind of clue as to how to solve these theories. But I haven’t talked about it in this lecture because I don’t see how that would work... I mean I couldn’t say that it was likely with any degree of sincerity, and certainly the LHC and any other accelerator that we can imagine being built will not get up to energies which are high enough so that we can directly see the structures that are described by superstring theory, the strings or the D-branes or whatever it is. Those will not be accessible at the LHC, so any clue we get will be very indirect."

"I myself, well I was working on superstring theory in the 80s and gave it up because... I moved into cosmology, which in the last couple of decades has had the excitement that elementary particle physics had in the 60s and 70s, a wonderful coming together of theory and observation. Cosmology now reminds me of the excitement that I felt when I was younger and doing particle physics... and it’s a pity that superstring hasn’t developed better. I still think it’s the best hope we have, I don’t know of anything else. My own work very recently has been trying to develop an alternative to superstring theory as a way of making sense out of quantum gravity at very high energies. But even though I’m working on this I still find superstring theory more attractive, but not attractive enough…"

BBC News: The Large Hadron Collider (LHC) experiment has once again become one of the coldest places in the Universe.

All eight sectors of the LHC have now been cooled to their operating temperature of 1.9 kelvin (-271°C)—colder than deep space.

The large magnets that bend particle beams around the LHC are kept at this frigid temperature using liquid helium.

The magnets are arranged end-to-end in a 27km-long circular tunnel straddling the Franco-Swiss border.

The cool-down is an important milestone ahead of the collider's scheduled re-start in the latter half of November as leaks earlier in the year delayed the restart of the LHC.

NYTimes.com: Holger Bech Nielsen, of the Niels Bohr Institute in Copenhagen, and Masao Ninomiya of the Yukawa Institute for Theoretical Physics in Kyoto, Japan, have suggested that the hypothesized Higgs boson, which physicists hope to produce with CERN's Large Hadron Collider, might be so abhorrent to nature that its creation would ripple backward through time and stop the collider before it could make one, like a time traveler who goes back in time to kill his grandfather.

Nielsen and Ninomiya put this idea forward in a series of papers: "Test of Effect From Future in Large Hadron Collider: a Proposal" and "Search for Future Influence From LHC," posted on the physics Web site arXiv.org.

According to the so-called Standard Model that rules almost all physics, the Higgs is responsible for imbuing other elementary particles with mass.

"It is our prediction that all Higgs producing machines shall have bad luck," Nielsen told the New York Times in an email.

Physics Today: Adlène Hicheur, a 32-year-old postdoc at the Swiss Federal Institute of Technology in Lausanne working on the Large Hadron Collider (LHC)—who was arrested in Vienne, France, last week—was charged earlier today on the suspicion of terrorism, say French and Swiss newspapers.

Hicheur had told investigators over the weekend that he corresponded over the internet with a contact in north Africa's al-Qaida branch, said French officials to the Guardian.

The exchange vaguely discussed plans for terror attacks, but nothing concrete was planned, the French official said, speaking on condition that his name not be used because the investigation is ongoing.

French counterterrorism and intelligence agencies have been tracking Adlène Hicheur for 18 months by reading his e-mails, says the Independent. They concluded in recent days that he had reached the "intention or desire stage" of preparing to mount an attack and arranged for his arrest.

Hicheur had been working at CERN on data analysis for the LHC since 2003. CERN issued a statement saying the following:

[Hicheur] was not a CERN employee and performed his research under a contract with an outside institute. His work did not bring him into contact with anything that could be used for terrorism: CERN is a particle-physics research laboratory whose research addresses fundamental questions about the universe. None of our research has potential for military application, and all our results are published openly in the public domain. CERN is providing the support requested by the French police in this enquiry.

Hicheur had previously worked on the BaBar experiment in the US, and at the Rutherford Appleton Laboratory in Oxfordshire, UK.

Related News Story
Hadron Collider physicist Adlene Hicheur charged with terrorism London Times

Wired.com: The Superconducting Super Collider has been a stain on US scientific history ever since the project was canceled in 1993 says Paul Berger in Wired magazine. It was hoped the collider would reveal new forms of matter and energy, like the elusive Higgs boson, by firing proton beams in opposite directions and smashing atoms into each other inside a 54-mile circular tunnel buried 250 feet underground (see photo of tunnel construction left). US physicists had to give up its project in Texas after Congress yanked funding—though not before the Department of Energy had built infrastructure, warehouses and almost 15 miles of underground tunnels at a $2 billion cost to the US taxpayer. The land and facilities are now up for sale, and yours for only $20 million. From the Physics Today archive SSC cost and size perplex Congress, Irwin Goodwin, May 1984 SSC design goes to DOE: ICFA discusses CERN hadron collider, Gloria B. Lubkin, June 1984 R & D funding for the Super Collider, Gloria B. Lubkin, October 1984 The SSC: A machine for the nineties, Sheldon L. Glashow and Leon M. Lederman, March 1985 Reagan endorses the SSC, a colossus among colliders, Irwin Goodwin, March 1987 The SSC vs Murphy's Law, Robert J. Yaes, Edwin L. Goldwasser, July 1987 Will High-T_c superconductivity affect the SSC's design? Irwin Goodwin, August 1987 Alternatives to the Superconducting Super Collider, Freeman Dyson, February 1988 Amazing race: The SSC contest generates disorder and discord, Irwin Goodwin, May 1988 SSC alternatives: Critics collide with Dyson, Edwin L. Goldwasser, Robert Siemann, Martin Einhorn and Gordon Kane, A. Abashian, and Freeman Dyson May 1988 SSC: Essential science or unnecessary expense? Robert E. Marshak, Lels L. Larson, Michael J. Glaubman, Daniel M. Smith, Steven Weinberg, John F. Waymouth, October 1988 Four reasons for forsaking the SSC, Truman Hunter, May 1990 A proposed detector for the SSC is approved, Bertram Schwarzschild March 1991 As SSC project accelerates, its cost exceeds $8.2 Billion, Irwin Goodwin, March 1991 What's gone wrong with the SSC? It's political, not technological, Irwin Goodwin, August 1992 Tunnel boring begins at Superconducting Super Collider, Bertram Schwarzschild, March 1993 Some thoughts on the SSC and the management of science, Sidney D. Drell, July 1993 Congress cancels SSC and allocates high budgets for technology in 1994, Irwin Goodwin, November 1993 An open letter to colleagues who publicly opposed the SSC, Leon M. Lederman, March 1994 The SSC's end: What happened? And what now?, Wolfgang K. H. Panofsky, Doug Pewitt, David R. Nygren, Pierre Ramond, Robert J. Reiland, Christopher Carone, Rustum Roy, March 1994 Reassigning blame for the SSC's demise, Timothy E. Toohig and Lawrence Cranberg, October 1994 Four years after SSC's demise, US Reaches agreement on `unprecedented' collaboration in CERN's LHC, Irwin Goodwin, January 1998

Physics Today: An article in the London Times that suggesting the UK was considering pulling out of the CERN has caused consternation in the physics community, and denials from the Science and Technology Facilities Council (STFC), but a review of the UK's science expenditure is ongoing.

The Science and Technology Facilities Council (STFC) has suffered from a financial crisis caused by over-spending on some high-profile projects such as the Diamond synchrotron light source. In response, STFC has cut back some grants and support for some facilities, and is conducting a major science review through its advisory panels, and with input from the science community and STFC's international partners. The report is due in December. The STFC has "to live within constrained budgets if need be, and to diversify our funding base," says STFC's Keith Mason.

A misquoted article

The Times article misquoted the STFC's chief operating officer Richard Wade, says Mason and took other comments out of context.

The UK's agreement with CERN is governed by an international treaty, and could only be changed with UK Government approval and with consultation with the other CERN partners, it cannot be made unilaterally by the STFC alone. It was the strength of this international agreement that during the 1980s, protected the UK's particle physics community's membership of CERN but also allowed the UK to negotiate a reduction in its membership fees.

CERN membership did however, have a knock on effect of leading to cuts in other areas of UK particle physics.

A vision for today

"The STFC's position in relation to the LHC is made clear in our July vision document," says Mason, "which states that 'our highest priority in particle physics is to exploit the Large Hadron Collider at CERN'."

The vision document also says that the UK's highest priorities in ground-based astronomy is to exploit membership of the European Southern Observatory, which gives access to the Very Large Telescope and to the ALMA millimeter astronomy array, and to carry out R&D towards the next generation European Extremely Large Telescope. The UK is also heavily involved in the proposed Square Kilometer Array radio telescope.

A bleak UK budget

However, the public sector, which funds the majority of research in the UK, is expected to suffer significant cuts next year because of the recession. The ongoing science review will "ensure STFC is prudently prepared for the tougher budget environment," says Mason, and "ask tough questions about the future direction of our science and technology program, including the balance between [science] disciplines."

The consultation encompasses all of STFC's programs, and includes an examination of the cost-effectiveness of international subscriptions, including CERN, the European Southern Observatory, the ILL neutron source and others.

"All UK publicly-funded bodies have a responsibility to ensure value-for-money," says Mason, "and STFC has discussed with our international partners the need to restrain costs and, if possible, reduce expenditure."

The next few months will be challenging says Mason, "but an exciting opportunity [for STFC] to set the course for the future."

Paul Guinnessy

BBC News: Engineers hope an early warning system being installed at the Large Hadron Collider could prevent incidents of the kind that shut down the machine last year.

Wired.com: Physicist Paul Halpern explores the past, present, and intriguing future of high-energy particle physics in Collider. He explains what all the hubbub surrounding the Large Hadron Collider is about and why physicists are pretty much beside themselves with anticipation.

Science: As they prepare to restart the Large Hadron Collider, accelerator physicists are confident that, instead of suffering a second catastrophic breakdown, the world's largest atom smasher will perform to the standards set by its predecessors—and give them lots of smaller headaches to struggle with.

Related News Pick
CERN confirms that LHC will run at 3.5 TeV
Students, researchers hit by Large Hadron Collider glitches

Physics Today: CERN's Director General, Rolf Heuer has confirmed that the Large Hadron Collider will run at 3.5 TeV leading to collisions at 7 TeV when it is turned on in November.

"We've selected 3.5 TeV to start," said Heuer, "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 lower energies are because not all the magnets appear to be working at full strength, and the copper stabilizer connections cannot be run at the higher energies.

Last year the LHC suffered a critical failure when one of the 10,000 high-current superconducting electrical connections failed. CERN has been cooling down and testing various sectors of the collider in order to track down the bad connectors.

The tests on the final two sectors concluded last week and have revealed no more major problems. This means that no more repairs are necessary for safe running this year and next.

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

The procedure for the 2009 start-up will be to inject and capture beams in each direction, take collision data for a few shifts at the injection energy, and then commission the ramp to higher energy.

The first high-energy data should be collected in December after the first beam of 2009 is injected. The LHC will run at 3.5 TeV per beam until a significant data sample has been collected and the operations team has gained experience in running the machine.

Gradually the machine will be raised up towards 5 TeV per beam. At the end of 2010, the LHC will be run with lead ions for the first time. After that, the LHC will shut down and work will begin on moving the machine towards 7 TeV per beam.

Various: The large number of electrical and vacuum issues effecting the Large Hadron Collider is having a trickle-down effect on both students and on researchers, some of whom are moving to Fermilab in an attempt to gather some data on the potential mass of the Higgs Boson.

Nature News reports on how a data drought is impacting students: Sara Bolognesi defended her PhD thesis last year on finding the Higgs boson based on theoretical calculations not data because of the LHC delays.

The long delays have ended the dreams of a generation of graduate students hoping to use fresh data for their theses. With no machine to deliver results, "people are doing experimental PhDs and effectively doing very little experimenting," says Will Reece, a graduate student at Imperial College London working on a detector known as LHCb. "It's a strange situation."

The New York Times's Dennis Overbye goes into more detail over the thousands of bad electrical connections that were discovered during the recent shut down to re-test the vacuum seals after last years accident.

Overbye says that CERN will announce a new schedule this week, and confirmed news that physicstoday.org reported two months ago that the collider will not now run 14 TeV collisions. Instead, due to the underperforming magnets, the collider will start operations at 8 TeV collisions.

In an e-mail exchange, Lucio Rossi, head of magnets for CERN, said that 49 magnets had lost their training in the sectors tested and that it was impossible to estimate how many in the entire collider had gone bad. He said the magnets in question had all met specifications and that the problem might stem from having sat outside for a year before they could be installed.

Related News Picks
LHC restart pushed back again
LHC restart pushed back, may not run at 14 TeV
LHC repair plan points to weaknesses in original design
Late start for Large Hadron Collider
Special focus on the Large Hadron Collider

Related Physics Today print articles
Mishap shuts down LHC until April November 2008
CERN's Fix-It Man November 2007
Multiple Problems Push LHC Start to Next Spring September 2007

Physics Today: The Large Hadron Collider is now on schedule to restart in the winter instead of the fall.

The LHC, which has been offline since September last year, has seen its schedule slip back at least three times in recent months as CERN grapples with a number of technical difficulties, including the risk that the collider may not reach 14 TeV. In a series of tests carried out over the last few weeks, CERN staff discovered vacuum leaks in two sectors of the LHC that had been cooled down to 80 K.

To repair the sectors have to be brought to room temperature—which has to be done gradually over a period of weeks—that will delay beam injection to mid-November says the CERN Bulletin.

On a brighter note the shutdown has allowed the various experimental groups to refine and improve their equipment. The CMS group finished a series of experiments with cosmic rays to align the detector, and refurbished the detectors cooling system. ATLAS has installed several upgrades they weren't expecting to install for a number of months. The GRID computer system has undergone full scale tests.

The final sector to be checked will be cooled down in August, which—if they find more leaks—may mean that the LHC could be delayed until the New Year.

Related News Pick
LHC restart pushed back, may not run at 14 TeV
LHC repair plan points to weaknesses in original design
Late start for Large Hadron Collider

Salon.com: The experience of CERN in having to counter widespread but baseless public concerns about black holes consuming the Earth is, more broadly, the experience of science in our culture today, say Chris Mooney and Sheril Kirshenbaum.

Science is simultaneously admired and yet viewed as dangerously powerful and slightly malevolent—an uneasiness that comes across repeatedly in Hollywood depictions.

As science-fiction film director James Cameron (Aliens, Terminator, Titanic) has observed, the movies tend to depict scientists "as idiosyncratic nerds or actively the villains."

That's not only unfair to scientists: It's unhealthy for the place of science in our culture—no small matter at a time of climate crisis, bioweapon threats, pandemic diseases, and untold future controversies that will surely erupt as science continues to dramatically change our world and our politics.

To begin to counter this problem, though, we need to wake up to a new recognition: Fixing the problem of science education in our schools, although very important, is not the sole solution. We also have to do something about the cultural standing of science—heavily influenced by politics and mass media—and that's a very different matter.

Physics Today: The Large Hadron Collider is on schedule to restart in the fall, but running three weeks late, says CERN Director General Rolf Heuer.

The delay will push back the restart of the project until October.

A bad break

The LHC has been offline since an incident on 19 September, caused by a faulty splice in the high-current superconducting cable between two superconducting magnets in sector 3-4.

There are more than 10,000 similar splices in the LHC, all of which are currently being checked for flaws.

The incident caused CERN to develop some noninvasive techniques to check for bad joints in the system while the collider is cooled down below 80 kelvin.

More than 39 dipole and 14 quadrupole magnets were taken to the surface for repairs.

Heuer told the CERN council last week that these tests indicate there could be another faulty splice in Sector 4-5.

CERN has also modified and conducted a major upgrade of the magnets' safety system to limit the damage another break could cause if a similar incident happens again.

14 TeV?

Meanwhile, the LHC may not run at full capacity for sometime. The existing repairs will allow the device to run at a collision energy of 8 TeV, but further modifications will be required to run at 10 TeV collision energy or higher.

According to reports of a talk given by Jörg Wenninger—who is from CERN Beams department's operation group—there are problems with quenching the magnets from one of the three firms that supplied CERN. This new quality control issue could mean that the LHC may not be able to go above 10 TeV collisions.

Related Link
Status of the LHC Machine