Category Archives: LHC Exhibition

CERN: 60 years of not destroying the world

Ahead of November’s opening of the Collider exhibition, Content Developer Rupert Cole celebrates six decades of research at CERN, the European Organization for Nuclear Research. 

Just before the Large Hadron Collider first turned on in September 2008, there was (in some quarters) a panic that it would destroy the world.

Doomsday was all over the media. “Are we all going to die next Wednesday?” asked one headline. Even when CERN submitted a peer-reviewed safety report in an attempt to allay fears, it didn’t altogether quash the dark mutterings and comic hysteria: “Collider will not turn world to goo, promise scientists.” 

This cartoon is pinned on the wall of the theory common room at CERN. Image credit: Mike Moreau

This cartoon is pinned on the wall of the theory common room at CERN. Image credit: Mike Moreu

In case you were wondering, the LHC has subsequently proved to be completely safe, and has even found the Higgs Boson to boot.

In fact, this isn’t the first time CERN has provoked fears of world destruction. In the lead-up to the signing of CERN’s founding Convention – 60 years ago this month – the proposed organisation was greatly hindered and influenced by apocalypse anxiety.

Only, back then, it had nothing to do with micro black holes swallowing the earth or strangelet particles messing with matter. No such exotic phenomena were needed. Just the mention of the words nuclear and atomic was enough to provoke serious paranoia in the Cold-War climate.

In 1949 Denis de Rougement, a Swiss writer and influential advocate for a federal Europe, attended the European Cultural Conference — one of the early conferences in which a “European Centre for Atomic Research” was discussed. “To speak of atomic research at that time,” de Rougement reflected, “was immediately to evoke, if not the possibility of blowing up the whole world, then at least preparations for a third world war.”

The press undoubtedly subscribed to the more extreme school of thought. On the second day of the conference, all the scientists present had to be locked in a chamber for protection as they had been pestered so severely by journalists on the previous day.

In some of the initial discussions, a nuclear reactor as well as an accelerator was proposed for the European research centre. It was carefully stressed that no commercial applications would be developed and all military work scrupulously excluded.

The French, who led these early proposals, removed the director of the French Atomic Energy Commission, the communist-leaning Frederic Joliot-Curie, after J. Robert Oppenheimer (of Manhattan Project fame) stated the Americans wouldn’t support a project that included a senior figure with Soviet sympathies.

Left to right: J. Robert Oppenheimer, Isidor I. Rabi, Morton C. Mott-Smith, and Wolfgang Pauli in a boat on Lake Zurich in August 1927. Image credit: CERN

Left to right: J. Robert Oppenheimer, Isidor I. Rabi, Morton C. Mott-Smith, and Wolfgang Pauli in a boat on Lake Zurich in August 1927. Image credit: CERN

The nuclear reactor was dropped when Hungarian-American physicist Isidor I. Rabi, the so-called “father” of CERN,  stepped on the scene. Rabi, who co-founded the American research centre Brookhaven National Laboratory, put a resolution to the annual conference of UNESCO in Florence, June 1950 for a (“western”) European physics laboratory.

The fact Rabi omitted to mention a nuclear reactor was likely a political move on the part of the US, who were not keen on Soviet bits of Europe developing nuclear weapons. After much to-ing and fro-ing in the next two years, a provisional agreement was signed on 14 February 1952 by ten European states.

The next day, the signed agreement was telegrammed to Rabi, informing him of the “birth of the project you fathered in Florence”. The convention was signed on the 1st July, 1953 and CERN became an official organisation just over a year later.

Telegram sent to Isidor Rabi on 15 February, 1952 – marking the birth of CERN. Image credit: CERN.

Telegram sent to Isidor Rabi on 15 February, 1952 – marking the birth of CERN. Image credit: CERN.

For sixty years, CERN has been successfully exploring the unknown regions of the quantum world, while leaving the world we live in very much intact.

See a copy of the telegram and more in Collider: step inside the world’s greatest experiment, opening this November. Click here for further reading on the history of CERN

Happy birthday, Z boson

Alice Lighton, content developer for our Collider exhibition, writes about the history of quantum physics. Collider: step inside the world’s greatest experiment opens in November 2013 with a behind-the-scenes look at the famous CERN particle physics laboratory. 

The air brimmed with excitement on this momentous day. The discovery of the particle confirmed a theory that had taken years to devise, and justified the toil of hundreds of scientists.

You might think I’m referring to the Higgs boson – the particle that explains mass, discovered at the LHC last year. But thirty years ago this month, another event shaped modern physics – the discovery of the Z boson.

In the 1960s, physicists predicted the Z and W bosons, as a way to link the electromagnetic and weak forces. There was plenty of evidence the theory was correct, but the lynchpin would be the discovery of the Z boson.

A section of the 4.3 mile-round Super Proton Synchrotron, at CERN near Geneva. Image: CERN

To make a Z boson, two particles are smashed together. The energy of the crash creates new, heavy particles. If a Z boson is produced, it sticks around for only a fraction of a second before it decays into other particles. To claim the prize of discovering the Z boson, physicists would need to be able to forensically reconstruct what happens in a collision, never seeing the Z directly.

Europe and America built machines to discover the Z, including the Super Proton Synchrotron (SPS) at CERN. “The idea of creating this massive object (the Z) and letting it decay…was a riveting idea (well at least for me in the late 1970s),” said Crispin Williams, a physicist who now works on the ALICE experiment at the LHC.

Two CERN physicists, effusive Italian Carlo Rubbia and Dutchman Simon Van der Meer, realised that to beat the firepower of the newly-opened Tevatron in Chicago, the SPS had to take risks. The pair devised an audacious plan; rather than fire beams onto a fixed object, they would collide two opposing beams, each only a hair’s width across and both travelling at almost the speed of light.

What’s more, one of the beams would be made of antimatter, which destroys ordinary matter. Creating and manipulating a beam of antimatter was a revolutionary concept.

Williams remembers when Rubbia and Van der Meer announced their plan to collide two beams. “This was to a packed auditorium at CERN and I suspect that most people thought he was out of his mind,” said Williams.

Rubbia and Van der Meer celebrate receiving a Nobel prize for their efforts. Image: CERN

Despite the technical challenge, the new collider worked. One visitor to CERN in 1982 described the intense excitement the new development created. “I went to the CERN cafeteria for a coffee and there I saw something that I had not noticed before. There was a monitor on the wall and people were watching the screen with great interest. The monitor was showing the rate of proton–antiproton collisions in CERN’s latest challenge – a bold venture designed to produce the intermediate bosons, W and Z.”

In January 1983, the risk-takers received their reward, when the W boson was discovered.  On 1st June 1983, scientists at CERN announced they had seen five Z bosons in their detectors.

The tracks left by the decay of the Z boson in a detector. Image: UA1/CERN

The route to the discovery had revolutionised particle physics, with more intricate detectors and the ability to manipulate antimatter. For Williams, the discovery of the Higgs boson was much less elegant. “In comparison the Higgs at the LHC is just brute force,” he said.  “Maybe I am just getting old and cynical: and I look back at the Z discovery through rose tinted glasses.”

LHC. Camera. Action! (Part 2)

Dr. Harry Cliff, a Physicist working on the LHCb experiment and the first Science Museum Fellow of Modern Science, writes about his recent filming trip to CERN for Collider, a new Science Museum exhibition opening in November 2013. The first part can be read here

Day 2, Thursday

On the first day of the Collider exhibition team’s visit to CERN we had explored the architecture and interiors of the town-sized laboratory. Now it was time to enter its beating heart: the gigantic experiments probing the fundamental laws of the universe, and the people who make them a reality.

Our team now divided. Pippa, Finn and crew set off to the far side of the 27km LHC ring to Point 5, home of the enormous Compact Muon Solenoid (CMS) experiment. 100 metres underground, 25 metres long, 15 metres high, weighing in at 12,500 tonnes and containing enough iron to build two Eiffel Towers, CMS is one of the four huge detectors that record the particle collisions produced by the Large Hadron Collider. It is also a remarkable sight, beautiful even, its concentric layers giving it the appearance of a gigantic cybernetic eye. One member of the team said it was the most incredible thing he had ever seen, with only the Pantheon in Rome coming close to matching it.

The enormous Compact Muon Solenoid (CMS) experiment. Credit: CERN.

The enormous Compact Muon Solenoid (CMS) experiment. Credit: CERN.

CMS was photographed from every angle so that it can be recreated in a 360 immersive projection for the Collider exhibition. The CMS team were incredibly accommodating in allowing us to get our cameras as close to CMS as possible, all while they carried out vital work on the detector. We owe particular thanks to the boundlessly energetic Michael Hoch who looked after us for the day and made it all possible.

Meanwhile, 13km around the ring, in a less spectacular CERN office, our radio producer and I carried out audio interviews of LHC physicists and engineers. Each of them sharing what makes them tick as scientists and inventors. One even surprised us by dismissing the discovery of the Higgs boson as “boring”; what drives him as a scientist is seeking answers to new questions. For him the Higgs threatens to be a dead-end on the journey of discovery, rather than opening up new avenues of inquiry. Over the course of the day we interviewed five members of CERN’s international community, drawn from across Europe, representing a diverse cross section of CERN’s most important asset, its people.

Day 3, Friday

The last day might have been the most challenging. The team assembled at CERN’s custom-built TV studio to film interviews with LHC engineers against a green screen. These are the people who build and operate CERN’s experiments and they will appear as full-body projections in the exhibition, as if museum visitors have wandered into the LHC tunnel to be met by a friendly member of staff. Over dinner the night before we had shared anxieties as to how it might go. Video, unlike audio, can’t be edited to remove fumbled words or long pauses – our interviewees would have to deliver near-perfect speeches, and none of them had ever done anything like this before. In fact, neither had any of us.

Our concerns were unfounded. The engineers were naturals and by the end of the day we had recorded some brilliant interviews that should really help bring CERN to life for the visitors to the exhibition.

We returned to London that evening, exhausted but carrying a huge amount of material, covering almost every aspect of the Large Hadron Collider. For the first time I really have a sense of what this Collider exhibition will become; it’s going to be quite something to see it take shape over the next five months. If you can’t make it to Geneva to see the LHC in person, you’ll find a healthy slice of the world’s greatest experiment at South Kensington this November. 

LHC. Camera. Action! (part 1)

Dr. Harry Cliff, a Physicist working on the LHCb experiment and the first Science Museum Fellow of Modern Science, writes about his work on Collider, a new Science Museum exhibition opening in November 2013.

In the past year, I’ve become a regular passenger on the evening flight from Gatwick to Geneva, home of CERN and the mighty Large Hadron Collider.  I think I could recite Easyjet’s pre-recorded safety announcement pretty much word-for-word if pushed. But this was a rather special trip, as I was visiting CERN perhaps for the last time on museum business.

I was accompanied by a team with a dazzling array of skills. Creative mastermind Pippa Nissen had marshalled exhibition designersgraphic designers, a sound artist, an animator, a camera technician and a radio producer. Not to mention our video designer, Finn Ross, fresh from his win at the Olivier Awards, and the inevitable after-party hangover. And me, a quantum superposition of particle physicist, curator and travel rep.

Our mission was to capture the essence of CERN so that it can be (almost literally) recreated in the Science Museum’s upcoming exhibition, Collider. All this material was to be gathered in just three days, using only cameras, microphones and the minds of our design team.

Day 1, Wednesday

One does not simply walk into CERN. Its gates are guarded by unfailingly helpful, though rather formidable, security personnel and to gain access you must produce a CERN ID card or a visitor pass.

CERN security gate.

CERN security gate. Image credit: Science Museum

We had rather brilliantly chosen the 1st of May as our day to arrive, a national holiday in Switzerland, meaning the reception where we would normally collect our passes was closed. I had arranged for them to be left with the security guard at the main gate, but conveying this to him proved a challenge in my halting GCSE French. Finally, with a bit of gesticulating and some help from our more linguistically capable graphic designer, we located the passes and stepped across the threshold into the world’s largest physics laboratory.

CERN is the size of a medium-sized town, spread across several sites, the largest of which straddles the border between the Swiss suburb of Meyrin and the French village of St-Genis-Pouilly. The lab grew up organically from its beginnings in the 1950s and is a peculiar hodgepodge of office buildings, warehouses and laboratories. CERN’s rather shabby above ground stands in stark contrast to the shining machines that inhabit its subterranean spaces. As far as is possible, the money goes underground, spent on CERN’s reason for being: exploring the unknown regions of the quantum world.

Our job on day one, however, was to explore CERN’s above ground world. The first few hours were spent photographing the exteriors of buildings to act as backdrops in the exhibition. There was a particular warehouse door, in varying shades of rust and faded blue, that really caught the team’s attention. It will take me a while to forget the image of the design team gathered around it while Finn took high-res shots with his £20k camera. That’s designers for you I suppose.

The long beige corridors of CERN's Building 2. Image credit: Science Museum

The long beige corridors of CERN’s Building 2. Image credit: Science Museum

Then we ventured into the star of the show, the enigmatic Building 2, a 1970s block that houses a large number of institute offices. Along its long beige corridors you find offices of universities from all over the world, including the room where Tim Berners-Lee invented the World Wide Web and my own home-away-from-home, the Cambridge LHCb office. We spent a happy afternoon photographing the office doors, each with their own personal details that do more than any museum text panel could in getting across just how international a place CERN is. We owe a particular debt of thanks to a PhD student from Bristol, in on a holiday to work on her thesis, who obligingly allowed us barge into her office to take photographs.

Meanwhile our sound designer was busily recording the soundscape of CERN from the clanging of doors and the echo of footsteps on lino to the hum of electrical equipment. Once we had recorded enough material to rebuild Building 2 in its entirety should any calamity befall it, we made a brisk trip around nearby parts of the lab, taking in the main auditorium where the discovery of the Higgs boson was announced to the world, and a series of labs and warehouses including the LEIR accelerator ring, the machine responsible producing beams of lead ions for our muse, the Large Hadron Collider.

But after all that, we had only scratched the surface of the sprawling laboratory. The next day it would be time to go underground…

A hundred years of the quantum atom

Alice Lighton, content developer for our Collider exhibition, writes about the history of quantum physics. Colider: step inside the world’s greatest experiment opens in November 2013 with a behind-the-scenes look at the famous CERN particle physics laboratory. 

A few years ago, a friend asked a question that took me somewhat by surprise. “Alice,” he said, “is quantum physics right, or is it just a theory?”

At the time I was in the midst of a physics degree, so my initial response was “I hope so!” Quantum physics matches up to experiment extraordinarily well – it is often called the most accurate theory ever. But the question, and subsequent conversation, made me realise how little many people know about the subject, despite its profound impact on modern life and the way we think about the universe.

This year is the centenary of the publication of one of the theories that laid the foundation for our understanding of matter in terms of quanta – packets of energy. According to quantum mechanics, light is not a wave, but lump of energy called photons. Max Planck came up with the idea at the end of the 19th Century, though he considered his light ‘quanta’ a useful model, rather than reality.

Niels Bohr

Niels Bohr, one of the founders of modern physics.

One hundred years ago, in 1913, the young Danish researcher Niels Bohr sent a paper to the Philosophical Magazine in London that used these quanta to solve a serious problem with theories about the atom. At the time, scientists thought the atom was like a solar systems; electrons orbit a nucleus of protons and neutrons. But anything that moves in a circle gradually slowly radiates energy, and so moves closer to the centre of orbit. Eventually, electrons should fall into the nucleus of the atom.

But they blatantly don’t, otherwise everything in the Universe would collapse, and we wouldn’t exist. Bohr proposed that electrons could only sit in discrete orbits or distances from the nucleus – and therefore when electrons change orbit transitions between orbits emit only emit energy in discrete packets (quanta), not gradually. The electrons therefore stay put in their orbits, and don’t fall into the nucleus of the atom.

A hydrogen atom is made from one electron orbiting a proton. Photo credit: flickr/Ludie Cochrane

Bohr was the first to show that packets of energy could successfully explain and predict the behaviour of atoms, the stuff that makes up you and me. His results were only approximately correct, but a big improvement of previous theories.

Generations of scientists have built on Bohr’s insight to understand and create the modern world. When my friend asked whether quantum physics worked, I pointed at his laptop. Computers, nanotechnology, and the Large Hadron Collider owe their existence to the physics that began with Bohr’s generation.

The CMS experiment at the Large Hadron Collider tries to work out the rules governing the sub-atomic world. Photo credit: CERN

Bohr’s original papers are clear and comprehensible, a beautiful read for physicists. The mathematics involves nothing more difficult than multiplication and division, yet the philosophical implications are immense. Max Planck never fully accepted quantum physics; neither did Albert Einstein, despite winning a Nobel Prize for his work on the subject.

Bohr also won a Nobel Prize for his quantum theory, but his work did not stop. He founded the Niels Bohr Institute, a centre of theoretical physics in Copenhagen, worked on the Manhattan Project developing the atomic bomb, and continued to make contributions to quantum mechanics.

And he has a lovely link to the exhibition I’m currently working on, about the Large Hadron Collider. Bohr was influential in the founding of CERN, the Geneva laboratory that is home to the LHC. If he had his way, the LHC would be in Denmark, but other scientists objected – Northern Europe was too cloudy, and had too few ski resorts, for Italian tastes.

An artists impression of the immersive collision experience in the Collider exhibition. Image credit: Science Museum / Nissen Richards Studio

Science Museum visitors to step into the greatest experiment on Earth

By Roger Highfield, Director of External Affairs at the Science Museum Group

Plans are unveiled today for the biggest-ever exhibition in the UK to focus on the Large Hadron Collider (LHC), the world’s greatest scientific experiment, where a 10,000 strong international army of scientists and engineers is exploring the fundamental building blocks of the universe, from the discovery of the Higgs particle to the nature of antimatter.

The King’s College theoretician John Ellis has suggested that the LHC, the most compelling scientific endeavour so far of the 21st century, could inspire a generation in the same way that the Apollo adventure did in the 1960s. That is precisely why the Science Museum is bringing the LHC to the public in its new Collider exhibition, opening in November 2013. Visitors will be transported right into the heart of the 27 km circumference machine – that straddles the border between Switzerland and France – with the help of an award-winning creative team including Nissen Richards Studio, playwright Michael Wynne and video artist Finn Ross.

An artists impression of the immersive collision experience in the Collider exhibition. Image credit: Science Museum / Nissen Richards Studio

An artists impression of the immersive collision experience in the Collider exhibition. Image credit: Science Museum / Nissen Richards Studio

The immersive exhibition, the result of a unique collaboration with CERN, the European Organization for Nuclear Research, will blend theatre, video and sound art, taking visitors to the site of the LHC where they can explore the Control Room and a huge underground detector cavern, meet ‘virtual’ scientists and engineers and examine objects up-close. “I particularly like the fresh, theatrical approach the Museum is taking to bringing the drama and excitement of cutting-edge science to the public,” said CERN Director General, Rolf Heuer.

View of the LHC tunnel. Image credit: CERN

View of the LHC tunnel. Image credit: CERN

For the first time, visitors can get up close with exclusive access to part of the large 15-metre magnets that steer the particle beam, and elements from each of the LHC’s ‘eyes’, four giant detectors housed in caverns around the machine, notably CMS and ATLAS, where collisions take place. They will also be able to follow the story of sub-atomic exploration through the Museum’s collections – on display will be J.J. Thomson’s apparatus which led him to the discovery of the electron in 1897, and the accelerator used by John Cockcroft and Ernest Walton to split the atom in 1932.

JJ Thomson (1856-1940) at work. Image credit: Science Museum / Science & Society Picture Library

JJ Thomson (1856-1940) at work. Image credit: Science Museum / Science & Society Picture Library

When in operation, trillions of protons race around the LHC accelerator ring 11,245 times a second, travelling at 99.9999991% the speed of light. Evidence for a Higgs-like particle was found in the aftermath of the resulting collisions between protons.

Named after the British physicist Peter Higgs who postulated its existence more than half a century ago, and who will help launch the new exhibition with other leading figures, the particle is the final piece of the Standard Model, a framework of theory developed in the late 20th century that describes the interactions of all known subatomic particles and forces, with the exception of gravity.

The highlight of the exhibition, according to Alison Boyle, the Science Museum’s curator of modern physics, will be a 360-degree projection taking in both extremes of the scale of the LHC. ‘We are going to take our visitors from an enormous experiment cavern to the very heart of a proton collision.

Artist's impression of the immersive detector experience. Image credit: Science Museum / Nissen Richards Studio

Artist’s impression of the immersive detector experience. Image credit: Science Museum / Nissen Richards Studio

Key figures from CERN, such as Professor Heuer, attended a gala ceremony held last month by the Fundamental Physics Prize Foundation at the Geneva International Conference Centre, hosted by Hollywood actor and science enthusiast Morgan Freeman with performances by singer Sarah Brightman and Russian pianist Denis Matsuev. Freeman mused that it was “a bit like the Oscars” and made the best joke of the night when referring to complaints about physicists ‘playing god’: “I have done it twice and I don’t see the problem.’

Yuri Milner, the Russian theoretical physicist turned internet entrepreneur who backs the prizes through his Milner Foundation, said it “celebrates what is possible in humanity’s quest to understand the deepest questions of the universe.”

The evening celebrated two Special Fundamental Physics Prizes of $3,000,000, one for Prof Stephen Hawking, who himself has been the subject of a special exhibition here at the Science Museum, for his discovery of Hawking radiation from black holes, and his deep contributions to quantum gravity and quantum features of the early universe, based on his efforts to combine theories of the very big (general relativity) with the very small (quantum theory). In his acceptance speech, Hawking thanked Milner for recognising key work in theory with what is now the most lucrative academic prize on the planet.

The second special prize was shared by the leaders of the LHC project, CMS and ATLAS experiments from the time the LHC was approved by the CERN Council in 1994: Peter Jenni, Fabiola Gianotti (ATLAS), Michel Della Negra, Tejinder Singh Virdee, Guido Tonelli, Joe Incandela (CMS) and Lyn Evans (LHC), for their role in the epic endeavour that led to the discovery of the new Higgs-like particle.

After they all took the stage Mr Matsuev performed Edvard Grieg’s “The Hall of the Mountain King”, presumably a reference to the great caverns in which the Higgs-like particle was first spotted. The award-winning biographer Graham Farmelo, who has advised on the development and launch of Collider, said it was ‘the most impressive gathering of great physicists for almost ninety years – since Einstein and most of the other discoveries of relativity and quantum theory met at the famous Solvay Conference in 1926’.

The Museum’s £1m Collider exhibition is part-funded by the Science and Technology Facilities Council, Winton Capital Management, the Embassy of Switzerland in the United Kingdom, and is supported by a number of individuals.

Collider will open in November 2013 and run for six months. Visits to Collider will be timed and, to avoid disappointment, please visit sciencemuseum.org.uk/collider to book tickets.

View of the LHCb cavern

X-citing news from CERN

Dr. Harry Cliff, a Physicist working on the LHCb experiment and the first Science Museum Fellow of Modern Science, writes about a new discovery at CERN for our blog. A new Science Museum exhibition about the Large Hadron Collider will open in November 2013, showcasing particle detectors and the stories of scientific discoveries.

In 2003 physicists at the Belle experiment in Japan reported they had discovered a brand new particle.

Adding a new entry to the big book of particle physics is certainly satisfying, but not usually cause for much excitement. The discovery of the Higgs-like boson last year was an exception. After all, hundreds of particles have shown up in experiments over the last century. So many in fact, that they were often referred to, rather derisively, as a “zoo”.

The Large Hadron Collider at CERN. Image Credit: CERN

But the particle found at Belle was different.

It didn’t fit neatly into the picture painted by theory and there was no clear explanation for its origin. It was a bit of an enigma, and earned a suitably enigmatic name: the X particle.

Professor Val Gibson from the University of Cambridge told me that she and her colleagues “have been mesmerized” about the identify this mysterious particle for the last ten years.

The Particle Zoo

The vast majority of the particles that make up the particle zoo are not fundamental; in other words they are made up of smaller things and these things are fundamental particles called quarks. Six different types of quark have been discovered and they can form a large number of different combinations, explaining the particle zoo.

However, quarks only bind together in very specific ways. Two ways in fact. One option is a ménage à trois known as a baryon. Baryons include the proton and the neutron, the building blocks of the atomic nucleus. The other option is where a quark and an antiquark couple up to form a meson.

The X didn’t fit easily into either of these pictures. This generated a lot of excitement and there was speculation as to whether it could be an ordinary meson, or some new exotic combination involving four quarks, a tetraquark, or a “molecule” of two mesons stuck together.

If this were true it would be the first time such an exotic state had been definitively seen in nature.

The only way to tell would be to measure the quantum numbers of the X, three properties that give a clue to its internal structure. This hadn’t been possible, until now.

Exciting, Exotic X

Amid the hundreds of trillions of collisions generated by the Large Hadron Collider over the past three years physicists at the LHCb experiment (the experiment I work on) managed to pick out about 300 X particles.

View of the LHCb cavern

View of the LHCb cavern. Image credit: CERN

This week, they presented the first full measurement of the quantum numbers of the X, at a conference at La Thuile in Italy. The result was emphatic – the X is not a meson, it is something altogether more exotic.

LHCb physicist Dr Matt Needham told me that “this measurement is a great step forward in understanding this mysterious X” and a “very exciting result”. However, there is still work to be done.

“The real nature (of the X) is still unclear”. Whether it’s a tetraquark, meson molecule or something else entirely must now be determined.

His colleagues at LHCb will now search for signs of the X decaying in new ways to try to separate out the various different options. Although the Large Hadron Collider has now shut down for two years physicists at LHCb will have no shortage of data to work with. An unprecedented sample was collected during 2012, corresponding to 180 trillion collisions, each one producing hundreds of particles.

The true nature of this enigmatic particle may soon be known. Whatever the result, we have now had our first glimpse of an altogether new state of matter. Finding out exactly what the X is will bring us deeper understanding of nature’s fundamental building blocks and the forces that bind them together.

Visitors to the Science Museum will have a chance to get up close and personal with the LHC at a new exhibition opening in November 2013. The exhibition will showcase real pieces of the LHC, including an intricate particle detector from the heart of the LHCb experiment.

LHC home screen Jan 3rd

The LHC’s Christmas Holiday

Over the past three weeks, deep under the Jura Mountains on the Swiss-French border, a monster has been sleeping. Over Christmas, the Large Hadron Collider, the world’s largest experiment, takes a break from colliding protons together in an underground tunnel. The machine normally runs for 24 hour-a-day, seven days a week, but for four weeks in January and December, it is switched off.

LHC home screen Jan 3rd

So long, and thanks for all the fish! The LHC operators look forward to their Christmas holiday.

There are several reasons for the extended break. The physicists, engineers and support staff who operate the machine and experiments are human. Yes, they are devoted to the search for the fundamental laws that govern the Universe, but they also like to indulge on Christmas pudding and see their families.

That explains why the LHC doesn’t run on Christmas day, but why does it shut down for three weeks?

Because it’s cold outside.

The cold doesn’t affect how the LHC works – far from it, as the machine is cooled to -271ºC. But it does affect the power supply.

One of the most intriguing facts I’ve learned over the course of working on the Science Museum’s upcoming LHC exhibition is that even though the LHC does an extremely specialised and power-consuming task – accelerating protons so they have the energy of a high speed train and are travelling at nearly the speed of light – the machine takes its power from the French grid. The same nuclear, coal and hydro-electricity plants that provide the energy to light the Mona Lisa and charge your mobile on holiday also power the LHC.

When it’s cold outside French electricity consumption spikes. In December, France uses about 50 percent more electricity than it does in August, heating, cooking and lighting dark days. When all systems are go, CERN can use as much as a third of Geneva’s power, or the same as a large town. So during darkest depths of winter, when the French grid is being stretched the most, the LHC powers down.

The time off isn’t wasted. Repairs and upgrades are always needed, so engineers have been busy tweaking to ensure the LHC is in tip-top condition for its run in 2013. From next week LHC will fire protons into lead nuclei for a month. After that short run, the machine shuts for two years for a serious upgrade.

Babbage's Difference Engine No 2, 1847-1849 drawings

Happy New Year

We’re welcoming in the New Year with a look at just a few of the exciting things happening here at the Museum in 2013.

Zombie hordes will invade the Museum in late January as we explore the science of consciousness and debate the ethical implications of a Zombie attack. Running during Lates and over a weekend, ZombieLab will feature live games, performances and talks from leading consciousness researchers across the UK.

Babbage's Difference Engine No 2, 1847-1849 drawings

Babbage’s Difference Engine No 2, 1847-1849 drawings

British philosopher and mathematician Charles Babbage, famous for his designs of automatic calculating machines, will be the focus of a new display this spring, as the Museum showcases the newly digitised Babbage archive and its collection of technical plans, drawings, scribbling books and letters.

In the summer, we’ll open Media Space, a brand new 1800 m² venue with two exhibition spaces and a café bar. A collaboration with the National Media Museum, Media Space will showcase some of the 3.2 million items from the National Photography Collection in a series of temporary exhibitions.

Media Space

Before work began on Media Space. Image © Kate Elliott

Photographers, artists and the creative industries will use our collections to explore visual media, technology and science through the wider programme of exhibitions and events at Media Space.

Finally, we’ll end the year with an exploration of one of the great scientific and engineering endeavours of our time: the Large Hadron Collider at CERN in Geneva.

Opening in autumn 2013, this new exhibition will give visitors a close-up look at remarkable examples of CERN engineering, including the vast dipole magnets. We’re working with CERN scientists and theatrical experts to produce a truly immersive experience which transports visitors into the heart of the LHC.

A Higgs boson is produced in the ATLAS detector

A Higgs boson is produced in the ATLAS detector at CERN

Also on display in the exhibition will be historic objects from our collections, including the apparatus used by JJ Thomson  in his electron discovery experiments and the accelerator Cockcroft and Walton used to split the atom.

So whether it’s Zombies, Media Space or the Large Hadron Collider that interests you, there’s something for everyone in the Museum this year.

A Higgs boson is produced in the ATLAS detector

The boring boson?

Last week scientists working on the Large Hadron Collider in Geneva updated their colleagues on the newly-discovered Higgs boson. They revealed what they now know about the particle – and so far, it is behaving exactly as they expected. While this might seem like good news, for some people it is the opposite, because a well-behaved Higgs might rule out some intriguing new physics theories.

A Higgs boson is produced in the ATLAS detector

A Higgs boson is produced in the ATLAS detector

The Higgs – the particle which explains why others have mass – is incredibly unstable and only exists for a fraction of a second before decaying into other, more common particles. Any information about it comes second-hand from these other particles, and working out the properties is rather like putting together clues in a Sherlock Holmes tale, only with more mathematics.

Finding the Higgs in July was a wonderful coup for the LHC, but there now follows years of painstaking work to determine its precise properties. If the Higgs behaves even a smidgen differently from predictions, then it might point scientists in the direction of a new theory.

One particularly popular idea has the rather grand name of “supersymmetry”, which as we wrote on this blog last week, is looking less likely to be true.

There are lots of problems with current theories about the Universe – they don’t explain dark matter, and particle physics is completely incompatible with Einstein’s theories of gravity. Supersymmetry solves some of these issues in a whizz of complicated mathematics, but requires the existence of a whole family of new particles. If they exist, the Higgs’ properties should reveal them.

The results announced on Wednseday in Japan don’t lend the under-fire supersymmetry any more support. They suggest that so far, the Higgs behaves just as our current theory predicts it should. Specifically, when it decays, it turns into different types of particles at the rates we expect.

To some in the community, the Higgs’ conformity is rather disappointing.  But not all of the analysis was ready for the Japan conference and there is still uncertainty around the results that were announced, and supersymmetry still could work.

Even though the LHC has already analysed more data in two years than its predecessor managed in twenty, the measurements are not yet particularly precise, and the Higgs may still harbour surprises. The LHC still has not detected a Higgs decaying into quarks (the smallest unit of matter), for example – we just know that since we haven’t seen it yet, it can’t happen often. In other words: watch this space.

Visitors to the Science Museum will have a chance to get up close and personal with the LHC at a new exhibition opening in November 2013.