CERN Open Data Portal: LHC experiments open to the Public

The web-based CMS event display, accessible through the CERN Open Data Portal, shows a proton-collision event recorded by the CMS detector. 

Credit: CMS /Open Data Portal

CERN today launched its Open Data Portal where data from real collision events, produced by experiments at the Large Hadron Collider (LHC) will for the first time be made openly available to all.

It is expected that these data will be of high value for the research community, and also be used for education purposes.

"Launching the CERN Open Data Portal is an important step for our Organization. Data from the LHC programme are among the most precious assets of the LHC experiments, that today we start sharing openly with the world."

"We hope these open data will support and inspire the global research community, including students and citizen scientists," says CERN Director-General Rolf Heuer.

The principle of openness is enshrined in CERN's founding Convention, and all LHC publications have been published Open Access, free for all to read and re-use.

Widening the scope, the LHC collaborations recently approved Open Data policies and will release collision data over the coming years.

The first high-level and analysable collision data openly released come from the CMS experiment and were originally collected in 2010 during the first LHC run.

This data set is now publicly available on the CERN Open Data Portal. Open source software to read and analyse the data is also available, together with the corresponding documentation.

The CMS collaboration is committed to releasing its data three years after collection, after they have been thoroughly studied by the collaboration.

"This is all new and we are curious to see how the data will be re-used," says CMS data preservation coordinator Kati Lassila-Perini.

"We've prepared tools and examples of different levels of complexity from simplified analysis to ready-to-use online applications. We hope these examples will stimulate the creativity of external users."

In parallel, the CERN Open Data Portal gives access to additional event data sets from the ALICE, ATLAS, CMS and LHCb collaborations, which have been specifically prepared for educational purposes, such as the international masterclasses in particle physics benefiting over ten thousand high-school students every year. These resources are accompanied by visualisation tools.

"Our own data policy foresees data preservation and its sharing. We have seen that students are fascinated by being able to analyse LHC data in the past and so, we are very happy to take the first steps and make available some selected data for education" says Silvia Amerio, data preservation coordinator of the LHCb experiment.

"The development of this Open Data Portal represents a first milestone in our mission to serve our users in preserving and sharing their research materials. It will ensure that the data and tools can be accessed and used, now and in the future," says Tim Smith of the CERN IT Department.

All data on OpenData.cern.ch are shared under a Creative Commons CC0 public domain dedication; data and software are assigned unique DOI identifiers to make them citable in scientific articles; and software is released under open source licenses.

The CERN Open Data Portal is built on the open-source Invenio Digital Library software, which powers other CERN Open Science tools and initiatives.

CERN: World Record Current in Superconductor

The 20-metre long electrical transmission line containing the two 20 kA MgB2cables. 

Credit: CERN

In the framework of the High-Luminosity LHC project, experts from the CERN Superconductors team recently obtained a world-record current of 20 kA at 24 K in an electrical transmission line consisting of two 20-metre long cables made of magnesium diboride (MgB2) superconductor.

This result makes the technology a viable solution for long-distance power transportation.

"The test is an important step in the development of cold electrical power transmission systems based on the use of MgB2," says Amalia Ballarino, head of the Superconductors and Superconducting Devices section at CERN.

"The cables and associated technologies were designed, developed and tested at CERN."

"The superconducting wire is the result of a long R&D effort that started in 2008 between CERN and the manufacturer, Columbus Superconductors in Genova, Italy."

The result was achieved at a temperature of 24 K (about -249 ˚C) using a test station that was purpose-designed and assembled at CERN.

The temperature is kept homogeneous over the 20-metre length of the line by a forced flow of helium gas.

Following intense development, the full 2 x 20-metre long MgB2 superconducting line was successfully powered to the world-record current of 20 kA, showing that this technology has great potential for the transmission of electrical power.

The superconducting properties of this relatively cheap material were discovered in 2001, but conductor technology only existed in the form of tape.

Round wire, which is more appropriate for assembling into high-current cables, was not available when the CERN project started.

"First, it was necessary to develop quality round wires adapted for use in this project, with high current density and uniform superconducting properties," says Ballarino.

"This work was done through a close collaboration between CERN and Columbus Superconductors, which manufactured different generations of wires with different architectures and with improved properties. In parallel, we at CERN developed the high-current cables and the electrical transmission line."

CERN LHC: Team announces beginning of restart

The team of scientists working at CERN's Large Hadron Collider (LHC) facility has reported to the press that the process of restarting the massive experimental mechanism has begun—though it won't finish until sometime next year. 

The world's most complicated system of machines will have to be restarted in pieces to ensure that each is operating properly before the next can be brought online.

Though proving the existence of the Higgs boson was a major goal, and achieving it garnered a lot of headlines, the facility at CERN has made progress in other areas as well, the creation of quark, gluon plasma back in 2011, is but one example.

Now the facility is in the process of an upgrade, which has been in the planning stages for several years and will include upgrades to several pieces and parts of the facility that support the LHC as well as the main accelerator itself.

The team recognized that the facility had begun to suffer from diminishing returns and that many parts could be improved due to the development of new technology and improvements on old ways of doing things.

Thus, this past February the LHC, along with other parts and accelerators that feed it, was shut down.

The retooling has been forecast to total approximately $4.4 billion dollars.

Thus far, the team has successfully restarted the part they call the source—the piece of equipment responsible for stripping electrons off of hydrogen atoms for use in producing protons.

Next up the team plans to fire up Linac2, an accelerator whose job it is to give protons their initial push.

After that a booster will be started that will be used to push the protons even faster.

For the LHC to be used in its proper context, it must receive protons that are already moving exceedingly fast.

Team members have made much of the complete upgrade to the control system for the LHC, the part that integrates all of the systems and which of course will be central to a successful reboot.

They should know early on if there are any problems. In addition to swapping out parts for new and improved technology, technicians will also be replacing worn cables or other minor but necessary components.

If all goes well, the LHC should be ready and back in business sometime early next year. Projects in the pipeline include: ALICE, CMS, ATLAS and LHCb.

Large Hadron Collider's CMS Tracker: Cool running required

The CMS Tracker Outer Barrel (TOB) shown in a clean room before its installation into the detector in 2008. 

Credit: Maximilien Brice/CERN 

By successfully passing a recent 'Master Cold Test', the CMS experiment Tracker has proved it can run at temperatures colder than ever before. 

It is now in shape to operate until 2025.

This Tracker, the closest subdetector to the collision point of Large Hadron Collider (LHC) particle beams, must face an onslaught of billions of particles flying through it each second of operation.

If the Tracker was operated at room temperatures, damage from this onslaught would soon render it inoperable.

So during the LHC's first run from 2010 to 2013, the Tracker operated at +4 °C, but with higher LHC beam intensities from 2015 onwards, the Tracker must operate at much colder temperatures, posing a monumental challenge to the Tracker community.

However, after two years of planning and one year of work, they have succeeded.

To achieve lower temperatures, many projects ran in parallel. The CMS cooling plant was refurbished and the fluorocarbon cooling system completely overhauled.

New methods for vapour-sealing and insulation helped suppress humidity inside the Tracker and several hundred high-precision sensors have improved humidity and temperature monitoring.

A new dry-gas plant now provides eight times as much dry gas (air or nitrogen) than before to help keep humidity away from the delicate electronics, and allows fine-grained regulation of the flow.

In addition, all cooling bundles outside the Tracker were equipped with heater wires and temperature sensors to guarantee safe operation in the future.

As a result, in early 2014 the Tracker successfully passed the important 'Master Cold Test' milestone, running the Strip Tracker at temperatures down to −20 °C with the Pixel Tracker lines going to −25 °C.

The subdetector was monitored continuously and performed as expected, without affecting the temperature of surrounding layers of the Electromagnetic Calorimeter, which operate at +18 °C.

Environmental conditions allow operation at −25 °C and the detector has been successfully operated at −20 °C.

To minimise thermal stress, researchers are discussing operating the Strip Tracker at −15 °C and the Pixel Tracker at −20 °C for the coming years.

With this milestone, the Tracker project has completed the bulk of its work for Long Shutdown 1 of the LHC.

The detector can now be operated cold with a sufficient safety margin. The team are now ready to track particles until Long Shutdown 3.

Post Higgs breakthrough, CERN readies for next cosmic quest

A view of the detector in the 12,500-ton Compact Muon Solenoid experiment (CMS). Image courtesy of CERN

A year ago, the world's largest particle collider made one of the greatest discoveries in the history of science, identifying what is believed to be the Higgs Boson—the long-sought maker of mass.

Today, its computer screens are dark, the control desks unstaffed and the giant, supercooled tunnel empty of the crashing proton beams whose snapshots of the Big Bang helped flush out the elusive particle.

But the silence is an illusion.

Behind the scenes, work is pushing ahead to give the vast machine a mighty upgrade, enabling it to advance the frontiers of knowledge even farther.

The 27-kilometre (17-mile) circular lab, straddling the French-Swiss border 100 metres (325 feet) underground, went offline in February for an 18-month overhaul.

When experiments resume in 2015, scientists at the European Organisation for Nuclear Research (CERN) will use its enhanced power to probe dark matter, dark energy and supersymmetry—ideas considered as wild as the Higgs Boson was, half a century ago.

As engineers focus on the technical mission, physicists are sifting through the mountains of data that the Large Hadron Collider (LHC) has churned out since 2010, for there could be more nuggets to find.

"The things that are easy to spot have already been exploited, and now we're taking another look," said Tiziano Camporesi of CERN, noting wryly that dealing with the unknown was, well, unknowable.

"We always say that astronomers have an easier task, because they can actually see what they're looking for!"

The LHC's particle collisions transform energy into mass, the goal being to find fundamental particles in the sub-atomic debris that help us to understand the Universe. At peak capacity, the "old" LHC managed a mind-boggling 550 million collisions per second.

"We give the guys as many collisions as we can," said Mike Lamont, head of its operating team. "That's our bread and butter."

"Most of that stuff is not very interesting, so there are real challenges sorting out and throwing most of that away, and picking out the interesting stuff," he explained in the tunnel, which mixes installations fit for a starship with the low-tech practicality of bicycles for inspection tours.

CERN LHC: New results indicate that Higgs boson particle is discovered

Event display of a H -> 4mu candidate event with m(4l) = 124.1 (125.1) GeV without (with) Z mass constraint. 

The masses of the lepton pairs are 86.3 GeV and 31.6 GeV. 

The event was recorded by ATLAS on 10-Jun-2012, 13:24:31 CEST in run number 204769 as event number 71902630.

Zoom into the tracking detector. Muon tracks are coloured red. 

Credit: ATLAS Experiment © 2012 CERN

At the Moriond Conference today, the ATLAS and CMS collaborations at CERN's Large Hadron Collider (LHC) presented preliminary new results that further elucidate the particle discovered last year.

Having analysed two and a half times more data than was available for the discovery announcement in July, they find that the new particle is looking more and more like a Higgs boson, the particle linked to the mechanism that gives mass to elementary particles.

It remains an open question, however, whether this is the Higgs boson of the Standard Model of particle physics, or possibly the lightest of several bosons predicted in some theories that go beyond the Standard Model. Finding the answer to this question will take time.

Whether or not it is a Higgs boson is demonstrated by how it interacts with other particles, and its quantum properties. For example, a Higgs boson is postulated to have no spin, and in the Standard Model its parity -- a measure of how its mirror image behaves -- should be positive.

CMS and ATLAS have compared a number of options for the spin-parity of this particle, and these all prefer no spin and positive parity. This, coupled with the measured interactions of the new particle with other particles, strongly indicates that it is a Higgs boson.

"The preliminary results with the full 2012 data set are magnificent and to me it is clear that we are dealing with a Higgs boson though we still have a long way to go to know what kind of Higgs boson it is." said CMS spokesperson Joe Incandela.

"The beautiful new results represent a huge effort by many dedicated people. They point to the new particle having the spin-parity of a Higgs boson as in the Standard Model. We are now well started on the measurement programme in the Higgs sector," said ATLAS spokesperson Dave Charlton.

To determine if this is the Standard Model Higgs boson, the collaborations have, for example, to measure precisely the rate at which the boson decays into other particles and compare the results to the predictions.

The detection of the boson is a very rare event -- it takes around 1 trillion (1012) proton-proton collisions for each observed event. To characterize all of the decay modes will require much more data from the LHC.

The above story is reprinted from materials provided by CERN, the European Organization for Nuclear Research.

CERN LHC: Particle collider to get energy boost

European particle physicists say the Large Hadron Collider in Switzerland will be run at higher energies in 2012 than in previous years

The higher energy 4 Tev level, 0.5 higher than levels used in 2010 and 2011, will allow the LHC to deliver the maximum possible amount of data this year before it goes into a long shutdown to prepare for even higher-energy running, a release from CERN headquarters in Geneva said Tuesday.

"When we started operating the LHC for physics in 2010, we chose the lowest safe beam energy consistent with the physics we wanted to do," Steve Myers, CERN's director for accelerators and technology, said.

"Two good years of operational experience with beam and many additional measurements made during 2011 give us the confidence to safely move up a notch, and thereby extend the physics reach of the experiments before we go into the LHC's first long shutdown."

In the last two years, the LHC has concentrated on narrowing the search for the Higgs boson, considered the foundation particle of particle physics.

However, to confirm its discovery or to rule out the Standard Model Higgs particle altogether will require one more year's worth of data, researchers said.

"By the time the LHC goes into its first long stop at the end of this year, we will either know that a Higgs particle exists or have ruled out the existence of a Standard Model Higgs," CERN's research director, Sergio Bertolucci, said.

"Either would be a major advance in our exploration of nature, bringing us closer to understanding how the fundamental particles acquire their mass, and marking the beginning of a new chapter in particle physics."

CERN Higgs boson: Tantalising Glimpse of 'God Particle' but No Discovery

Scientists at at the CERN particle physics laboratory outside Geneva have found signs of the Higgs boson, but stopped short of claiming a full discovery of the so-called 'God particle'.

The leaders of the two teams of researchers, ATLAS and CMS, revealed their findings on Tuesday to a packed seminar at CERN, where they have been trying to find the elusive particle using the £6.2 billion Large Hadron Collider (LHC) built to recreate conditions a fraction of a second after the Big Bang.

The researchers were keen to stress they were not making an announcement saying that the particle definitely exists, but that the new data is strong enough to suggest the question will be answered next year, one way or another.

Physicist Fabiola Gianotti, head of the ATLAS team, said the particle is more likely to be found in lower mass or energy ranges, a discovery they only made recently. This means that the search for the "God particle" has now been narrowed down to a signal centred at around 126 GeV (Giga electron volts).

"I think it would be extremely kind of the Higgs boson to be here, but it is too early," Professor Gianotti said during the seminar.

"More studies and more data are needed. The next few months will be very exciting... I don't know what the conclusions will be."

The results showed a spike in the graph taken by the ATLAS and CMS teams, where the apparent Higgs boson began to decay after temporarily existing when the LHC smashed particles together.

Oliver Buchmueller, a senior physicist on the CMS team, said: "We see a small bump around the same mass as the Atlas team and that is intriguing.

It means we have two experiments seeing the same thing and that is exactly how we would expect a Higgs signal to build up."

Speaking at the end of the seminar, CERN director Rolf Heuer summed up the findings by saying: "These are preliminary results, we're talking small numbers and remember that we are running [the LHC] next year.

"The window for the Higgs mass gets smaller and smaller, but it is still alive. We have not found it yet. Stay tuned for next year.

"But be careful - it's intriguing hints," he said. "We have not found it yet, we have not excluded it yet."

If CERN discovers that the Higgs boson does not exist after all, physicists will have to undertake a massive rethink of how the universe works and how particles obtain their mass after spending decades searching for this elementary particle.

The Higgs boson is named after particle physicist Peter Higgs, who proposed the idea in 1964.

CERN Physicists Anxiously Await News of Higgs Boson

High noon is approaching for the biggest manhunt in the history of physics.

On Tuesday morning, scientists from CERN, the European Center for Nuclear Research, are scheduled to give a progress report on the search for the Higgs boson — infamously known as the “God particle” — whose discovery would vindicate the modern theory of how elementary particles get mass.

The report comes amid rumors that the two competing armies of scientists sifting debris from hundreds of trillions of proton collisions in CERN’s Large Hadron Collider, or L.H.C., outside Geneva, have both finally seen hints of what might turn out be the elusive particle when more data is gathered next year.

Alternatively, the experimentalists say that a year from now they should have enough data to rule out the existence of the most popular version of the Higgs boson, sending theorists back to their blackboards in search of another explanation of why particles have mass.

So the whole world will be watching.

ESA Cluster Mission: Cosmic particle accelerators

ESA's Cluster satellites have discovered that cosmic particle accelerators are more efficient than previously thought.

The discovery has revealed the initial stages of acceleration for the first time, a process that could apply across the Universe.

All particle accelerators need some way to begin the acceleration process. For example, the Large Hadron Collider (LHC) at CERN employs a series of small accelerators to get its particles up to speed before injecting them into the main 27 km-circumference ring for further acceleration.

In space, large magnetic fields guide particles known as cosmic rays across the Universe at almost the speed of light, but are notoriously bad at getting them moving in the first place.

Now ESA's Cluster mission has shown that something similar to the 'staging' process used at CERN is happening above our heads in the natural particle accelerators of space.

On 9 January 2005, Cluster's four satellites passed through a magnetic shock high above Earth. The spinning craft were aligned almost perfectly with the magnetic field, allowing them to sample what was happening to electrons on very short timescales of 250 milliseconds or less.

The measurements showed that the electrons rose sharply in temperature, which established conditions favourable to larger scale acceleration.

It had long been suspected that shocks could do this, but the size of the shock layers and the details of the process had been difficult to pin down.

Steven J. Schwartz, Imperial College London, and colleagues used the Cluster data to estimate the thickness of the shock layer. This is important because the thinner a shock is, the more easily it can accelerate particles.

"With these observations, we found that the shock layer is about as thin as it can possibly be," says Dr Schwartz.

Thin in this case corresponds to about 17 km. Previous estimates had only been able to tie down the width of the shock layers above Earth at no more than 100 km.

This is the first time anyone has seen such details of the initial acceleration region.

Particle Physics: TRIUMF Photowalk 2010

Click on the Image to view all the photos in Flickr

The Large Hadron Collider Experiment Really Matters

After a series of setbacks, scientists have done it. They've mashed protons together at 99 percent of the speed of light and at a record-high energy level of 3.5 trillion electron volts.

The experiment took place at the Large Hadron Collider (LHC) near Geneva, Switzerland but scientists around the world watched excitedly via live feed. What does this mean for the field?

• This Is a Big Deal! exclaims Geoff Brumfiel at Nature: "I can't think of another case where the future of an entire field hinges on the success of a single experiment...It could verify current theories of particle physics, most notably the Higgs mechanism, which endows all matter with mass. It could also discover new physics beyond the current 'standard model', and explain some current mysteries in physics like 'dark matter', a mysterious form of matter that makes up around 85% of all matter in the universe."

• Why Scientists Are Excited Melissa Franklin, Professor of Physics at Harvard, explains what this means for the scientific community in an interview late last year:
  Sean Gallup/Getty Images After a series of setbacks, scientists have done it. They've mashed protons together at 99 percent of the speed of light and at a record-high energy level of 3.5 trillion electron volts.

• Don't Expect Instant Results, cautions LHC Spokesman Guido Tonelli to the BBC: "Major discoveries will happen only when we are able to collect billions of events and identify among them the very rare events that could present a new state of matter or new particles. This is not going to happen tomorrow. It will require months and years of patient work."

• This Is What Science Is All About, rejoices Stacey Higginbotham at Gigaom: "The LHC built by CERN represents why I spend my days writing about technology — not because I’m excited to play with the latest gadgets, but because I value the spirit of curiosity and discovery that leads scientists to spend $16 billion to build something that may (not will, but may) give us an inkling about how the universe works."

• Happy First Physics Day, declare the editors of Big Think: "Now there is a new March holiday, First Physics Day, which is being celebrated today because the particles in the Large Hadron Collider are finally being smashed together at super high energies that mirror conditions after the Big Bang. The physics community is aflutter over the potential of bagging the elusive Higgs boson, and the rest of us are grateful that, improbable as it seemed, the collider did not create a fatal black hole."
  

Large Hadron Collider to jump to maximum energy

Large Hadron Collider to jump to maximum energy - Short Sharp Science - New Scientist

The Large Hadron Collider is going to skip medium-energy proton collisions, jumping straight to its maximum energy in 2013, after it finishes collecting lower-energy data and has its circuitry upgraded.

The particle accelerator, located outside Geneva, Switzerland, has recovered from its 2008 accident. And in 2009 it broke the world record for particle collision energy when its two oppositely directed proton beams each reached 1.18 TeV, for a total energy of 2.36 TeV.

That made it slightly more powerful than its US competitor, Fermilab, which has been colliding particle beams with energies of 1 TeV, adding up to a total energy of 2 TeV.

After a brief holiday hiatus, the LHC is getting ready to start up again. Its managers have decided to carry out collisions for two years at 3.5 TeV per beam. At the end of 2011, it will shut down for a year for circuitry upgrades, returning in 2013 at its maximum design energy of 7 TeV per beam, or 14 TeV in total.

There had been talk of pushing the LHC to a middling energy of 5 TeV per beam prior to the shutdown at the end of 2011. But scientists apparently decided that was not worth the risk. During the shutdown, the LHC's electrical connections will be upgraded, making it more robust against short circuits of the kind that caused the 2008 accident.

While the LHC ramps up to maximum energy, Fermilab still has a chance of beating it to the discovery of the long-sought Higgs particle – responsible for endowing other particles with mass – but only if the Higgs turns out to be relatively lightweight.

LHC: Large Hadron Collider shut down until February 2010

Scientists have switched the world's most powerful atom-smasher to standby for two and a half months, the European Organisation for Nuclear Research (CERN) said on Friday.

The Large Hadron Collider (LHC) ended the year "in style", CERN said, achieving more than a million particle collisions in the last two weeks and accelerating proton beams to energy levels never reached before.

CERN said the LHC would be restarted in February after a short technical stop to prepare it for collisions at even higher energy levels.

"Commissioning work for higher energies will be carried out in January, along with necessary adaptations to the hardware and software of the protections systems," CERN said in a statement.

The 3.9 billion-euro (5.6 billion dollar) collider was relaunched in November after 14 months out of action because of an electrical fault.

Scientists hope to use the collider -- inside a 27-kilometre (16.8-mile) tunnel straddling the Franco-Swiss border -- to understand the origins of the universe by recreating the conditions that followed the Big Bang.

So far, the LHC has achieved collisions at an energy level of 2.36 teraelectronvolts (TeV), and CERN wants to reach 7.0 TeV to try to recreate the conditions of the Big Bang.

Before the LHC experiment, no particle accelerator had exceeded 0.98 TeV. One TeV is the equivalent to the energy of a flying mosquito.

The LHC aims to resolve physics problems including "dark matter" and "dark energy", thought to account for 96 percent of the cosmos.

The scientists' Holy Grail is to find a theorised component called the Higgs Boson, which would explain how particles acquire mass.

LHC sets new world record for energy particle accelarator

CERN's Large Hadron Collider has today become the world's highest energy particle accelerator, having accelerated its twin beams of protons to an energy of 1.18 TeV in the early hours of the morning.

This exceeds the previous world record of 0.98 TeV, which had been held by the US Fermi National Accelerator Laboratory's Tevatron collider since 2001. It marks another important milestone on the road to first physics at the LHC in 2010.

"We are still coming to terms with just how smoothly the LHC commissioning is going," said CERN Director General Rolf Heuer. "It is fantastic. However, we are continuing to take it step by step, and there is still a lot to do before we start physics in 2010. I'm keeping my champagne on ice until then."

These developments come just 10 days after the LHC restart, demonstrating the excellent performance of the machine. First beams were injected into the LHC on Friday 20 November.

Over the following days, the machine's operators circulated beams around the ring alternately in one direction and then the other at the injection energy of 450 GeV, gradually increasing the beam lifetime to around 10 hours. On Monday 23 November, two beams circulated together for the first time, and the four big LHC detectors recorded their first collision data.

Last night's achievement brings further confirmation that the LHC is progressing smoothly towards the objective of first physics early in 2010. The world record energy was first broken yesterday evening, when beam 1 was accelerated from 450 GeV, reaching 1050 GeV (1.05 TeV) at 21:28, Sunday 29 November. Three hours later both LHC beams were successfully accelerated to 1.18 TeV, at 00:44, 30 November.

"I was here 20 years ago when we switched on CERN's last major particle accelerator, LEP," said Research and Technology Director Steve Myers. "I thought that was a great machine to operate, but this is something else. What took us days or weeks with LEP, we're doing in hours with the LHC. So far, it all augurs well for a great research program."

Next on the schedule is a concentrated commissioning phase aimed at increasing the beam intensity before delivering good quantities of collision data to the experiments before Christmas. So far, all the LHC commissioning work has been carried out with a low intensity pilot beam. Higher intensity is needed to provide meaningful proton-proton collision rates.

The current commissioning phase aims to make sure that these higher intensities can be safely handled and that stable conditions can be guaranteed for the experiments during collisions. This phase is estimated to take around a week, after which the LHC will be colliding beams for calibration purposes until the end of the year.

Prof John Womersley, Director Science Programmes at STFC said; "this is another fantastic milestone for the LHC. To see such a complex project make progress at this impressive rate is testament to the tremendous efforts that have been made by all of those involved. I look forward to seeing the continued success of the LHC and to early 2010 when we can expect it to deliver the first data for physics analysis".

First physics at the LHC is scheduled for the first quarter of 2010, at a collision energy of 7 TeV (3.5 TeV per beam).

Large Hadron Collider (LHC) first synch test succesful

The Large Hadron Collider (LHC) has circulated two beams simultaneously for the first time, allowing the operators to test the synchronization of the beams and giving the experiments their first chance to look for proton-proton collisions.

With just one bunch of particles circulating in each direction, the beams can be made to cross in up to two places in the ring. From early in the afternoon, the beams were made to cross at points 1 and 5, home to the ATLAS and CMS detectors, both of which were on the lookout for collisions. Later, beams crossed at points 2 and 8, ALICE and LHCb.

"It's a great achievement to have come this far in so short a time," said CERN Director General Rolf Heuer. "But we need to keep a sense of perspective - there's still much to do before we can start the LHC physics program."

Beams were first tuned to produce collisions in the ATLAS detector, which recorded its first candidate for collisions at 14:22 this afternoon. Later, the beams were optimized for CMS. In the evening, ALICE had the first optimization, followed by LHCb.

"This is great news, the start of a fantastic era of physics and hopefully discoveries after 20 years' work by the international community to build a machine and detectors of unprecedented complexity and performance," said ATLAS spokesperson Fabiola Gianotti.

"The events so far mark the start of the second half of this incredible voyage of discovery of the secrets of nature," said CMS spokesperson Tejinder Virdee from Imperial College London.

"It was standing room only in the ALICE control room and cheers erupted with the first collisions," said ALICE spokesperson Jurgen Schukraft. "This is simply tremendous."

"The tracks we're seeing are beautiful," said LHCb spokesperson Andrei Golutvin, "we're all ready for serious data taking in a few days time."

These developments come just three days after the LHC restart, demonstrating the excellent performance of the beam control system. Since the start-up, the operators have been circulating beams around the ring alternately in one direction and then the other at the injection energy of 450 GeV.

The beam lifetime has gradually been increased to 10 hours, and today beams have been circulating simultaneously in both directions, still at the injection energy.

Professor Norman McCubbin, Head of Particle Physics at the Science and Technology Facilities Council's Rutherford Appleton Laboratory said, "Achieving low-energy collisions in the LHC so quickly after the re-start is a huge boost for the worldwide particle physics community. We look forward eagerly to the next stages in commissioning the LHC and to embarking on our quest to unlock new secrets of the Universe as the machine becomes fully operational."

Prof. John Womersley, Director Science Programmes at STFC said, "The CERN accelerator team is doing a tremendous job and I congratulate them on achieving this vital step on the way to full operation of the LHC. As a scientist who has worked on this kind of machine myself, I understand the challenges involved - from here the CERN team will be working on increasing the number of particles in the beams and gradually ramping up the energy of these particles. The LHC will soon be the highest energy particle accelerator in the world, and in 2010 we can expect to see it start delivering new science."

Next on the schedule is an intense commissioning phase aimed at increasing the beam intensity and accelerating the beams. All being well, by Christmas, the LHC should reach 1.2 TeV per beam, and have provided good quantities of collision data for the experiments' calibrations

Large Hadron Collider (LHC) Switched On again

A picture of the Large Hadron Collider taken while under construction

Scientists have switched on the world's largest atom smasher for the first time since the £6bn machine suffered a spectacular failure more than a year ago.

It has taken a year of repairs for beams of protons to once again be circulated in the Large Hadron Collider, which had been heavily damaged by a simple electrical fault.

The European Organisation for Nuclear Research has taken the restart of the collider step by step to avoid further setbacks as it moves towards new scientific experiments - probably starting in January - regarding the make-up of matter and the universe.

Progress on restarting the machine, on the border between Switzerland and France, went faster than expected and the first beam circulated in a clockwise direction around the machine at about 10pm local time, said spokesman James Gillies.

"Some of the scientists had gone home and had to be called back in," he said.

The exact start time of the Large Hadron Collider was difficult to predict because it was based on how long it took to perform steps along the way, and in the end it happened about nine hours earlier than expected, Mr Gillies said.

This is an important milestone on the road towards scientific discoveries at the LHC, which are expected in 2010, he said.

About two hours later the scientists circulated another beam in the opposite direction. The LHC also will be used later for colliding lead ions - basically the nucleus of the element that is about 160 times as heavy as a single proton. That should reveal still more scientific secrets.

"It's great to see beam circulating in the LHC again," said 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 first beams were circulated on September 10, 2008. But the machine was sidetracked nine days later when a badly soldered electrical splice overheated and set off a chain of damage to massive superconducting magnets and other parts of the collider, in a 17-mile circular tunnel under the Swiss-French border. £24.2m has been on repairs and improvements to avoid a repetition.

CERN: Large Hadron Collider (LHC) stalled by Piece of Bread

The rehabilitation of the beleaguered Large Hadron Collider was on hold tonight after the failure of one of its powerful cooling units caused by an errant chunk of baguette.

The $4 billion particle-collider faced more than a year of delays after a helium leak stymied the project in its first few days of operation. It is gradually being switched back on over the coming months but suffered a new setback on Tuesday morning.

Scientists at the CERN particle physics laboratory in Geneva noticed that the system’s carefully monitored temperatures were creeping up.

Further investigation into the failure of a cryogenic cooling plant revealed an unusual impediment. A piece of crusty bread had paralysed a high voltage installation that should have been powering the cooling unit.

The cooling systems are in place to keeps the collider functioning at a temperature of 1.9 degrees above absolute zero. As soon as there is a small rise in temperature the super-conducting magnets stop functioning and fail safes come into operation to control the collider.

A spokeswoman for CERN confirmed that baguette was responsible for the latest hiatus, but she conceded that mystery surrounded the way it got into the vital power installation, which is protected by high security fences.

“Nobody knows how it got there,” she told The Times. “The best guess is that it was dropped by a bird, either that or it was thrown out of a passing aeroplane.”

“Obviously this was slightly surprising. Within the team there was some amusement once they had relaxed after initial concerns.”

The bread was discovered on a busbar - an electrical connection inside one of eight buildings above ground on the 17-mile (27km) circuit in the Swiss countryside.

The spokeswoman said: “The collider extends over a very large area – you have to have a very comprehensive system to try to avoid problems of this kind. We’re talking about a couple of days down time.”

Scientists hope that the temperature will be restored by around midnight tonight allowing work to continue. The failure of the cooler meant the temperature rose around 5 degrees to the equivalent of about -266C.

The first beams were injected into the LHC on September 10 last year, but nine days later a connection between two magnets failed. This caused a huge leak of the helium that cools the ring around which protons will be fired against one another at 99.9999991 per cent of the speed of light.

The leak inflicted further damage, and the accelerator was mothballed so that 53 magnets could be replaced. Engineers have since found and replaced other magnet connections that could have been at risk of causing a repeat of the fault, and installed other safety features to prevent another fault.

Tevatron tightens up the race with LHC for the Higgs - New Scientist

(Image: Fermilab)

Tevatron near Chicago could be in the running to discover the Higgs boson

WITH the Large Hadron Collider (LHC) still in the repair shop, the race to find the Higgs boson has become a lot tighter, thanks to the older and less powerful but functioning, Tevatron collider near Chicago.

"The Tevatron definitely has a chance," says Greg Landsberg of Brown University in Providence, Rhode Island, who works on one of the LHC's detectors.

With the LHC due to restart only in November at CERN near Geneva, Switzerland, the Tevatron has been gaining ground in the search for the Higgs, the particle thought to give mass to other elementary particles. At last week's Lepton Photon conference in Hamburg, Germany, Tevatron physicists said that by early 2011 they will have recorded enough data to allow them to either find or rule out the Higgs as predicted by the standard model.

Tevatron physicists said that by early 2011 they will have the data to either find the Higgs or rule it out

The LHC will have to sprint to catch up, and it won't be easy. While the LHC's higher energies should produce more Higgs particles, it will also boost the production of other particles that can mimic a Higgs, says Gordon Kane of the University of Michigan in Ann Arbor. Telling between the two will require a precise understanding of how the LHC's detectors are working, which takes time to develop.

The LHC, however, could become the first to find particles of dark matter, a search for which the Tevatron is not well suited

(LHC) Large Hadron Collider Restarts, at half speed

(Image: CERN)

A technician inspects the site of a faulty electrical connection that damaged the LHC in September 2008

The world's most powerful particle smasher will restart in November at just half the energy the machine was designed to reach. But even at this level, the Large Hadron Collider has the potential to uncover exotic new physics, such as signs of hidden extra dimensions, physicists say.

CERN Lab

The LHC is a new particle accelerator at the CERN laboratory near Geneva, Switzerland, designed to answer fundamental questions, such as what gives elementary particles their mass, by colliding particles at higher energies than ever achieved in a laboratory before.

The First Attempt

The first attempt to turn on the LHC failed in September 2008 when a joint connecting a pair of superconducting wires overheated, causing an explosive release of helium used as a coolant. Scientists have been making repairs and checking the strength of other electrical connections since then to pave the way for a second start attempt.

Restart November

Now, CERN has announced that the LHC's first data collecting run, to begin in November, will collide protons at only half the energy the accelerator was designed to achieve. The run will initially smash protons together at 7 trillion electron volts (7 TeV), compared to the design goal of 14 TeV, according to a CERN statement on 6 August. (Protons in each of the two opposing beams will have 3.5 TeV of energy, producing collisions at 7 TeV.)

Even 7 TeV is much higher than physicists have ever probed in the laboratory before. The Tevatron accelerator at Fermilab in Batavia, Illinois, is the current record holder, with collisions at 2 TeV.