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 1585.

    The LHC is too big & expensive to fail.

    I'm told that neither the quark nor the neutrino nor the gluon nor the messenger photon have ever been detected singly & unambiguously.

    You may put me right on these matters, if you can.

    Meanwhile, I'll stick to my considered opinion that there is no such thing as the Higgs boson.

    BTW, real science welcomes criticism. It's how we used to move forwards.

  • rate this

    Comment number 1584.

    What, no posts for ten minutes? Have we all gone quiet? Or perhaps this thread is about to be cut o....

  • Comment number 1583.

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

  • rate this

    Comment number 1582.

    @1573. Lacenbastion

    “Science did not invent the BBC website. People did.”

    Yes, using technology devised by science. QED.

  • rate this

    Comment number 1581.

    Funny coincidence. This side of the pond, we are saying that we may have strong evidence (as scientists we are cautious) that the Higgs boson exists.

    On the other side, the NOS has had to issue a statement warning Americans that there is no evidence for the existence of mermaids, and mind you, that's only going to get some folks there started out with conspiracy theories ;)

  • rate this

    Comment number 1580.

    So, E=MC^2. & now we know the origin of M!

    OK, now that's done & dusted, can we commandeer some of these brainy types to sort out the ECONOMY please in the place of the numbwits wrecking it at 1000s of times their salaries?

    Thank you.

  • rate this

    Comment number 1579.

    1565. Wuuf: Okay, I'll take that bet...but in £ if you don't mind. Why not throw in a little currency speculation? I've doubts about hohlraums and whether you can spit them into position at the rate required.

  • rate this

    Comment number 1578.

    A hearty 'Well Done' to every one involved. The reason this discovery is important is that many aspects on not just Physics, but biology and chemistry too, relies on their Standard model. If this was proved inaccurate, it would mean scrapping decades of work, and starting again.

  • rate this

    Comment number 1577.

    @1567 Rambo. Rather sad view.

    You could say that being able to post a comment about a scientific discovery on a website viewed by lots pf people is in itself a proof of the valdity of the scientific method - what you call squanderous.

    Maybe you should be complaining to the BBC on parchment sent by horse and cart.

  • rate this

    Comment number 1576.

    There is no relevance to any major world religion in this discovery and it is no more an attempt at disproving God than an advance in geology that dates the world or astronomy that demonstrates the true structure of the heavens.

    The only thing that usually disproves a religion is the contents of its own holy book being provably false. The more you define god the easier he is to discredit.

  • rate this

    Comment number 1575.

    I can't express how proud and excited I am. I honestly have a very little idea about mass and physics in general (the teachers at my school sucked, so I hardly learned anything, only stuff I read by myself) but I read about Cern and Colliders-LHC and particle science months ago and now all of this is happening and I'm so excited I just can't believe what a huge leap science has made. Bravo.

  • rate this

    Comment number 1574.

    @1567. Rambo

    “I am sooo impressed by all the brainy scientists who made all this tremendous acheivement possible that us "thickos" couldn't possibly understand.”

    Your words, not mine. But even if you don’t understand particle physics, you’re obviously quite capable of using something developed from it, i.e., a computer (although perhaps not the spell checker).

  • rate this

    Comment number 1573.

    @1558 Science did not invent the BBC website. People did.

    Currently this finding is of use to only a small society of people. Theorists. What will be truly interesting is if in 10 years we're still taking about how it was used by and for people.

  • rate this

    Comment number 1572.

    People who say this is a waste of money need to learn how the economy works. The billions invested in this doesn't just disappear into thin air.

    The money pays for the livelihood of the scientists who work in the facility, the builders who built the facility, the people who supplied materials to build the facility, the people who maintain the facility etc etc

    And as a bonus we learn new things

  • rate this

    Comment number 1571.

    @1537. Rambo
    Part of the "squanderous waste of our taxes" created the internet at CERN which you are using now. Should we not have invested in that given that millions depend on this technology for work? Who are you to decide what science is invested in? I pay taxes too and am more than happy for it them to be used for this - as are most people commenting here; its investing in our future.

  • rate this

    Comment number 1570.

    My oh my this topic has some legs. As the man said earlier, geeks know how to parteh!

    However, for God's, sorry, Higg's sake, it's a BOSON. A bosun is a sailor, who has a sort of chair named after him.

    Perhaps to avoid this confusion, it should be called a Religion. This would satisfy both the God-botherers and the geeks.

  • rate this

    Comment number 1569.

    I wonder therefore if we can find a way of managing our numbers then ???

  • rate this

    Comment number 1568.

    One more "particle" to add to the "pile".

    Until we are able to emancipate ourselves from the notion of beginnings and endings we may never escape the false premise of a “universe” as an entity.

    To escape time and cheat the bell, were that possible could I tell? ("Big Bang - Fact or Fiction” John C Vetterlein.)

  • rate this

    Comment number 1567.

    OOh I am sooo impressed by all the brainy scientists who made all this tremendous acheivement possible that us "thickos" couldn't possibly understand. Strange, therefore, that we all have to pay for all this squanderous waste out of our taxes ! I am off down Tescos for a bag of particles tomorrow. Eh Up Lad. Ecky Thump.

  • rate this

    Comment number 1566.

    Despite being a bunch of monkeys in shoes, we really are quite brilliant sometimes. To think that there are people worrying about the latest x-factor winner when there is stuff like this going on.

    From the theory, to the idea, to the engineering, to the experiments, to the data, to the result, I'm so happy that we can all celebrate just how important intelligent people are to us.


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