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 1545.

    Does the Higgs boson get its not inconsiderable mass from interactions with other Higgs bosons or by directly interacting with the Higgs Field?

  • rate this

    Comment number 1544.

    1522. postingdude - We have to be very careful about castigation here, where would we be without the disbelievers of a flat Earth or everything revolving around the Earth. As someone else has commentated on here, what created the Higgs? 1531. Golgotha - Found in SA 2010 not yet named believed to be another link to Homo Hibillis etc!

  • rate this

    Comment number 1543.

    and now I think it might be to time for some Vogon poetry............... that'll stop them in there tracks, mucking about inconvincecing all those hard working electrons


  • rate this

    Comment number 1542.

    Predication of Higgs Boson - Englishman (Higgs)
    Invention of the web - Englishman (Berners-Lee)
    Invention of the bagless vacuum cleaner - Englishman (Dyson)...

    Rule Britannia !!

  • Comment number 1541.

    All this user's posts have been removed.Why?

  • rate this

    Comment number 1540.

    now that i know how my tea cup works. is it still a tea cup?

  • rate this

    Comment number 1539.

    Just a thought
    If we diverted the annual world wide spending on weapons (currently $1.5 trillion & rising) & instead invested it into solving poverty,clean water for all, cheap energy for all, access to medical facilities for all etc.Not a hope in Hell.

    But here is the research the naysayers WILL back.

    The ability to kill ever more people at a greater distance with the flick of a finger !

  • rate this

    Comment number 1538.

    what? did you even listened the press conference? or have any idea how bosons are observed? or am i not a physics major like you are not? yeah. must be that one.

  • rate this

    Comment number 1537.

    I sometimes wonder why these brilliant scientists with their big brains don't sometimes try and do something useful with their lives. How many of these academics run employment schemes for the young ? How many run their own companies. How many have ever worked in the "real" world. How many have ever contributed to the real economy ? None of them.

  • rate this

    Comment number 1536.

    @ #1053 "the higgs field is composed of countless billions of higgs particles." That is not correct. In the ground state there are no Higgs bosons but there is an allpervasive field that should explain mass. I still have to see a confirmation that this new particle is indeed teh long-sougt Higgs. I think this is still to be proven. It could be any unknown particle.

  • rate this

    Comment number 1535.

    1533. Roddy

    I'm sure people said the same about Photons.

  • rate this

    Comment number 1534.

    Science is the future in the making and possibly a turning point in our existence. Maybe the world needs a big find to change our attitude towards one another for the better. We have developed technology but have lost our way and by achieving this, perhaps as a species we can achieve much more for the greater good of mankind.

  • rate this

    Comment number 1533.

    OK, so it exists. What are we supposed to do with it though? I doubt we could ever have much control over it.

  • rate this

    Comment number 1532.

    I am really appalled by how narrow minded and trivial some comments are - whilst everyone has the right for their view to be heard, unfortunately some views will be more valid than others - some comments on the surface look really valid, but actually just demonstrate the writer's deep lack of understanding on the subject.

    If you have nothing positive to say, please say nothing.

  • rate this

    Comment number 1531.


    " Ah 1891 (all that can be discovered has been discovered), then what about that found in 2008, 2010 etc?"

    Why what was found in 2008 and 2010 that has changed our understanding of human evolution and now claims a "missing link" between Man and Ape?

  • rate this

    Comment number 1530.

    1512. Golgotha - Ah 1891 (all that can be discovered has been discovered), then what about that found in 2008, 2010 etc?

  • rate this

    Comment number 1529.

    Truly amazing, especially when Higgs the predictor of finding such a scientific discovery is alive and kicking to enjoy the accolades. What this means to our, only the scientific establishment will finally find out, and too if it benefits mankind even greater is it`s importance, wonderful stuff.

  • rate this

    Comment number 1528.

    A great day in the history of science. Congrats to all concerned. Centuries of work, sacrifice and talent lead to our understanding of the standard model and now with more of the same this is the final piece of the jigsaw puzzle - more to do of course...

    What a contrast to the anti-scientific, religious fanatics "the world was made 7000 years ago" nonsense based upon nothing more than dogmatism.

  • rate this

    Comment number 1527.

    what puzzles me is if it is so fundamental to the fabric of the universe why has it been so hard to find

    Yeah, I've got a molecules set so I know hydrogen atoms are black, oxygen red, nitrogen blues all joined together by straws and now they're saying the straws aren't true. Honestly, you don't know who to believe....!

  • rate this

    Comment number 1526.

    Hunar M

    In science there is no such thing as fact, only theory. Theory = explanation. One theory only last as long as it takes for the next explanation.

    That is the beauty of science. It is not arrogant like religious explanation, fixed for all time. Scientific method is just a means of developing the next theory. Religious method is a means of preventing inquiry.


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