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 1425.

    1414 Paul (ie me)

    I should've said 'A theorem in maths can be proved to be true or false (mostly)'. There's a 3rd possibility - it's not provable.

    But the point remains, all a genius needs to prove a theorem is a pen and some paper. If he gets a result, he's finished.

    A physicist needs a £2.6bn budget and can only tell for sure if it's false. It's never 100% true. That isn't a criticism, BTW.

  • rate this

    Comment number 1424.


    Actually there has always been calls by those in the know to stop calling it the "God Particle" becuase it's an inaccuarte discription. The whole "God Particle" thing comes from Lederman, "so central to the state of physics today, so crucial to our understanding of the structure of matter, yet so elusive [The Higgs Boson]..." It has nothing to do with God or Mysticism

  • rate this

    Comment number 1423.

    #1396՝ Higgs particle can exist unbound to fermions that is the result announced. No it could not therefore be dark matter as it lasts for the tiniest part of a second before radiating as photons or leptons which are not 'dark'. If there are more than on type of higgs particle i.e heavy ones for instance, then dark matter may be super partners of SM partictles. This is what they hope is true.

  • rate this

    Comment number 1422.

    1414. Paul - A theorem in maths can be proved to be true or false.

    Not true. That is why there are a whole list of theorems that have million pound prizes against them in the hope that someone can prove (or disprove) them.

    1415. Golgotha

    Don't need Cern. I have a couple of really good bottles of Chablis that should do it!

  • rate this

    Comment number 1421.

    but what is the point?

  • rate this

    Comment number 1420.

    1374. DownTheShore: Imagine a special kind of treacle that only creates drag on spoons with a specially shaped hole in them. Spoons without that specially shaped hole zip straight through the treacle unaffected. The specially shaped hole is the Higgs particle, the treacle is the Higgs 'field', and the drag is what we perceive as 'mass'. The spoons are fundamental particles, or entire planets.

  • rate this

    Comment number 1419.

    @ 1412.Bellatori

    "They were once the forefront of science."

    Yes, a LONG time ago, and haven't progressed a day since.

  • rate this

    Comment number 1418.

    1405. Golgotha
    Don't be stupid. If the sum of your experience is having a couple of pints and seeing the hag turn into the desirable blonde you are barking up the wrong tree. BH is the beginning not the end."
    I don't drink so I've not experienced that, do "hags" really turn into "desirable blondes" after a couple of pints?
    They do, but then they disappear, hick

  • rate this

    Comment number 1417.

    Firstly, EPIC congratulations to the scientists at CERN! This is the type of thing that makes me feel proud of being a human being

    =>As long as you aren't arrogant enough to believe humanity is the last in the evolutionary line. The dinosaurs had a long reign, so have we. Maybe something from CERN will fire up our successors?

  • rate this

    Comment number 1416.

    A remarkable success for the engineers and workers who built the LHC as much as for the scientists who used the enormous machine to find the fabric that binds much else together. As it wouldn't go amiss to praise the thousands that built this Colossal machine as much as the theorists who proposed the idea because without the hard work of these people the Higgs field would still be theoretical.

  • rate this

    Comment number 1415.


    "1405. Golgotha - I don't drink so I've not experienced that, do "hags" really turn into "desirable blondes" after a couple of pints?

    So rumour has it..!?"

    I've just formulated the "Golgotha particle" theory to try to explain a shift in mass which allows complete transformation of an individuals physique when consuming C2H5OH. Can we use CERN to test it?

  • rate this

    Comment number 1414.


    I also take my hat off to the sheer power of maths. IMHO it completely demolishes the argument that only 'practical' endeavours are worthwhile.

    But this stuff is physics, and physicists will tell you it's a very different beast to maths. A theorem in maths can be proved to be true or false. A theory in physics can only be shown to be false.

  • rate this

    Comment number 1413.

    Noticed now that is has been discovered, the atheist, anti God media have stopped calling it : 'The God particle '
    Science is proving what Mystics have 'known', God is, and is in, everything.
    This is his Kingdom, we are His agents.
    Que: ranting atheists blinded by ego of The Fool

  • rate this

    Comment number 1412.

    1406. Jim - Everything in the universe has its opposite.

    That's what I am praying for or my younger daughter is never going to get married...!?

    1405. Golgotha - I don't drink so I've not experienced that, do "hags" really turn into "desirable blondes" after a couple of pints?

    So rumour has it..!?

    1409. Chris - we'd all be living like Muslims.

    They were once the forefront of science.

  • rate this

    Comment number 1411.

    What would Richard Feynman have said and how would he have explained it ?

  • rate this

    Comment number 1410.

    "To a gnostic god is an experience not a Holy Book."
    Only because at some point in your life, somebody TOLD you what to believe and what to feel, Dr. Bob

    =>Secret is in the word"gnostic". It can only come from within the individual. All you can be taught is how to start looking. In fact, not unlike the CERN effort in that respect. god is just a word.

  • Comment number 1409.

    This comment was removed because the moderators found it broke the house rules. Explain.

  • rate this

    Comment number 1408.

    We need math to explain everything, its means man knows everything.

  • rate this

    Comment number 1407.

    The following statement was published in an anthology in 1996:
    "A famous 100-year-old painter who survived repeated setbacks and tribulations in the turmoil of China, said: Truth, justice and beauty -- through the vicissitudes of history -- these things remain constant... ."
    'Creative finances" largely contribute to the ongoing economic crises of the United States and Europe. Compare.

  • rate this

    Comment number 1406.

    Firstly, EPIC congratulations to the scientists at CERN! This is the type of thing that makes me feel proud of being a human being.

    Secondly, if there are two particles, could it be an anti-Higgs particle? Everything in the universe has its opposite. How would that change our level of understanding on physics?

    Finally, we found the universal superglue!


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