Higgs boson-like particle discovery claimed at LHC


The moment when Cern director Rolf Heuer confirmed the Higgs results

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Cern scientists reporting from the Large Hadron Collider (LHC) have claimed the discovery of a new particle consistent with the Higgs boson.

The particle has been the subject of a 45-year hunt to explain how matter attains its mass.

Both of the Higgs boson-hunting experiments at the LHC (Atlas and CMS) see a level of certainty in their data worthy of a "discovery".

More work will be needed to be certain that what they see is a Higgs, however.

Prof Stephen Hawking tells the BBC's Pallab Ghosh the discovery has cost him $100

The results announced at Cern (European Organization for Nuclear Research), home of the LHC in Geneva, were met with loud applause and cheering.

Prof Peter Higgs, after whom the particle is named, wiped a tear from his eye as the teams finished their presentations in the Cern auditorium.

"I would like to add my congratulations to everyone involved in this achievement," he added later.

"It's really an incredible thing that it's happened in my lifetime."

Prof Stephen Hawking joined in with an opinion on a topic often discussed in hushed tones.

"This is an important result and should earn Peter Higgs the Nobel Prize," he told BBC News.

"But it is a pity in a way because the great advances in physics have come from experiments that gave results we didn't expect."


The CMS experiment team claimed they had seen a "bump" in their data corresponding to a particle weighing in at 125.3 gigaelectronvolts (GeV) - about 133 times heavier than the protons that lie at the heart of every atom.

The BBC's George Alagiah explains the Higgs boson

They claimed that by combining two data sets, they had attained a confidence level just at the "five-sigma" point - about a one-in-3.5 million chance that the signal they see would appear if there were no Higgs particle.

However, a full combination of the CMS data brings that number just back to 4.9 sigma - a one-in-two million chance.

Prof Joe Incandela, spokesman for CMS, was unequivocal: "The results are preliminary but the five-sigma signal at around 125 GeV we're seeing is dramatic. This is indeed a new particle," he told the Geneva meeting.

The Atlas experiment results were even more promising, at a slightly higher mass: "We observe in our data clear signs of a new particle, at the level of five sigma, in the mass region around 126 GeV," said Dr Fabiola Gianotti, spokeswoman for the Atlas experiment at the LHC.

Peter Higgs Peter Higgs joined three of the six theoreticians who first predicted the Higgs at the conference

Prof Rolf Heuer, director-general of Cern, commented: "As a layman I would now say I think we have it."

"We have a discovery - we have observed a new particle consistent with a Higgs boson. But which one? That remains open.

"It is a historic milestone but it is only the beginning."

Commenting on the emotions of the scientists involved in the discovery, Prof Incandela said: "It didn't really hit me emotionally until today because we have to be so focussed… but I'm super-proud."

Dr Gianotti echoed Prof Incandela's thoughts, adding: "The last few days have been extremely intense, full of work, lots of emotions."

A confirmation that this is the Higgs boson would be one of the biggest scientific discoveries of the century; the hunt for the Higgs has been compared by some physicists to the Apollo programme that reached the Moon in the 1960s.

Statistics of a 'discovery'

Swiss franc coin
  • Particle physics has an accepted definition for a "discovery": a five-sigma level of certainty
  • The number of standard deviations, or sigmas, is a measure of how unlikely it is that an experimental result is simply down to chance, in the absence of a real effect
  • Similarly, tossing a coin and getting a number of heads in a row may just be chance, rather than a sign of a "loaded" coin
  • The "three sigma" level represents about the same likelihood of tossing nine heads in a row
  • Five sigma, on the other hand, would correspond to tossing more than 21 in a row
  • Unlikely results are more probable when several experiments are carried out at once - equivalent to several people flipping coins at the same time
  • With independent confirmation by other experiments, five-sigma findings become accepted discoveries

Scientists would then have to assess whether the particle they see behaves like the version of the Higgs particle predicted by the Standard Model, the current best theory to explain how the Universe works. However, it might also be something more exotic.

All the matter we can see appears to comprise just 4% of the Universe, the rest being made up by mysterious dark matter and dark energy.

A more exotic version of the Higgs could be a bridge to understanding the 96% of the Universe that remains obscure.

Scientists will have to look at how the Higgs decays - or transforms - into other, more stable particles after being produced in collisions at the LHC.

Dr Pippa Wells, a member of the Atlas experiment, said that several of the decay paths already showed deviations from what one would expect of the Standard Model Higgs.

For example, a decay path where the Higgs transforms into two photon particles was "a bit on the high side", she explained.

These could get back into line as more statistics are added, but on the other hand, they may not.

"We're reaching into the fabric of the Universe at a level we've never done before," said Prof Incandela.

"We're on the frontier now, on the edge of a new exploration. This could be the only part of the story that's left, or we could open a whole new realm of discovery."

The Standard Model and the Higgs boson

Standard model

The Standard Model is the simplest set of ingredients - elementary particles - needed to make up the world we see in the heavens and in the laboratory

Quarks combine together to make, for example, the proton and neutron - which make up the nuclei of atoms today - though more exotic combinations were around in the Universe's early days

Leptons come in charged and uncharged versions; electrons - the most familiar charged lepton - together with quarks make up all the matter we can see; the uncharged leptons are neutrinos, which rarely interact with matter

The "force carriers" are particles whose movements are observed as familiar forces such as those behind electricity and light (electromagnetism) and radioactive decay (the weak nuclear force)

The Higgs boson came about because although the Standard Model holds together neatly, nothing requires the particles to have mass; for a fuller theory, the Higgs - or something else - must fill in that gap

Paul.Rincon-INTERNET@bbc.co.uk and follow me on Twitter


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  • rate this

    Comment number 1485.

    Peace on every one! Very shortly, I want to ask a simple question to the Committee who have done this really scientific discovery. What will happen or become to a bit of soil after a year, if the so-called theory 'Higgs Boson' is true? Or, what will be the future of the bottom of sea-life? Because, →

  • rate this

    Comment number 1484.

    1467. stewart - absolutely spot on and what happens, you get marked down for it. I believe there are sentient beings out there that regard our progress and intelligence as currently on the single cell scale. There is a lot to be said for Men In Black. How many times in History has fantasy become reality? 1471. What Mandate - Surely you mean real science as our race understands it!!!!

  • rate this

    Comment number 1483.

    1477. rockandhardplace - and so on infinitesimally

    Actually there are very good reasons to believe that we can divide atoms to particles (P,N e) and they can be made from quarks but quarks are the bottom of the pile. Not only is there no evidence for smaller particles than quarks but there are good reasons to believe there are not and that quarks are indivisible. I could suggest a book..!! #1476

  • rate this

    Comment number 1482.


    ... or even a Richard Hawking thread. ;)

  • rate this

    Comment number 1481.

    Congratulations to the LHC team and the research teams around the world who contributed.
    On the 4th of July 2012, the inhabitants of a nondescript planet that orbits a some what minor star in the milky way galaxy took a step closer to understanding the fabric of the Universe itself.

  • rate this

    Comment number 1480.

    @1473 Robert.

    I think the term 'God particle' isn't meant to taken literally, or to be attributing its existence to God. It is just that it was a postulated about and previously invisible particle, that couldn't be proved to exist - like God.
    This isn't a Stephen Dawking thread so there's no need to bring religion into it. cheers.

  • rate this

    Comment number 1479.

    Its so frustrating to read comments saying this has no direct use so its a waste. Electrons where discovered and at the time had no use; imagine a world without power. Quantum physics had no use at the time but allowed the creation of electonics. The web was created in the same way. Its called discovery. We discover then spawn a technology we cannot even imagine today - thats a snip at 10bn.

  • rate this

    Comment number 1478.

    @1444 I do not fully disagree with you, but your comment is somewhat misleading. Bose (along with Einstein and others) helped establish the general physics of integral spin particles, or bosons. Higgs (along with 5 others) helped develop the very specific theory of the Higgs mechanism and Higgs field. The Higgs particle is just one thing; bosons are a class of particles.

  • rate this

    Comment number 1477.

    Not to come across as a sceptic but why do we assume that to have life you must have water and similarly if there is a so-called higgs bosun why wouldn't there be something beyond that? Has anyone else noticed that everything we know is round or constructed of round elements. We are specks enclosed in bigger specks, so on and so on and so on infinitesimally.

  • rate this

    Comment number 1476.

    1462. KY_Red - You obviously need to read more. The beauty of the current model IS its simplicity. I should get commission for recommending Bruce Schumms book Deep Down Things but it is a superb explique of the model in reasonable laymen's terms.

    The underlying symmetry is breathtaking in its simplicity.

  • rate this

    Comment number 1475.

    signed in for the first time for a year just to vote down the comments saying its a waste of money, and what is this achieving!....ironic as CERN gave us the web in the past, though these people would be more interested in solving a ms marple puzzle than fermats last theorem

  • rate this

    Comment number 1474.

    Until science investigates and embraces the so-called paranormal, and marries it with the scientific method, knowledge and understanding of the strange workings of the universe is going to remain in the slow lane. You make significant advances by doing things differently.

  • rate this

    Comment number 1473.

    Please stop using the phrase "God particle". Must every action a scientist does be allied with religion? Believe it or not, science is for every person on the planet, not just your religious readers.

  • rate this

    Comment number 1472.

    What do they, the scientists, do with the God's particle? Play God?
    Everything is much more complicated than the scientists can imagine. Most of their theories are based on quicksand.

  • rate this

    Comment number 1471.

    This is a great day that will go down in history. Not because of a crooked banker, or a new DG or even Andy Murray making the semifinals, but because mankind had just taken a giant step forward in understanding how the universe actually works. Theoretical physics is all very well, but today it became real physics and despite what many may think, that really does matter if we want a better world.

  • rate this

    Comment number 1470.

    Well done to all involved. Amazing - and to think that they admit to understanding less than 4% of the universe. That's humbling in itself!

    Now, if this IS the 'God Particle', and it gives mass to matter, does that mean that all atheists are now weightless?

  • rate this

    Comment number 1469.

    I have to admit that although I am a reasonably bright kind of bloke.,I don't really have the foggiest idea what has been discovered .It looks like everybody with a PHD in Physics is very excited about it. I will just have to wait for Bill Bryson to explain it to me in his next edition of " A Short History of Nearly Everything".

  • rate this

    Comment number 1468.

    Satyendra Nath Bose whose pioneering work in the early 1920s identified the particles which bear his name"

    Bose (with Einstein) described the class of particles known as bosons. He had nothing more to do with this specific type of boson, any more than Enrico Fermi had to do with variants of the other class of particles known as Fermions, such as the quark.

  • rate this

    Comment number 1467.

    Great news about the discovery of the Higgs. Probably won't sleep tonight with excitement. Only one question. What made the Higgs in the first place?

  • rate this

    Comment number 1466.

    What better Birthday Present could I ask for? A stupendous success for collaboration and the variety of theorists, pragmatists, activists and reflectors that went to make up this team at LHC.


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