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."

'Dramatic'

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
    +5

    Comment number 165.

    @ AM, it appears by your comment that you greatly misunderstand what is meant and accepted as a scientific theory. Perhaps you should understand this first before commenting.

    Also spending money on scientific exploration is better spent, than spending money on cathedrals and churches. Scientific research benefits everybody. You wouldnt be commenting on here without research into the quantum world

  • rate this
    +4

    Comment number 164.

    At last.. intelligence being reported from the BBC .. why cant the BBC make headlines that relate more to Science achievements.. the country of Iran alone .. published 120,000 scientific reports in 2008.. oh that might be too political to report...

  • rate this
    +5

    Comment number 163.

    141.Richard

    Because it only exists for tiny, tiny fractions of a second. It may be a building, but it's one that vanishes!

    149.penguin337
    If you want a full briefing, Google Is Your Friend. Don't expect complex science in 400 characters. If you want to know the uses - wait 10 years or so. And take a look at the laser in your cd drive - that was supposedly useless when it was invented.

  • rate this
    +4

    Comment number 162.

    I've read this and seen the news reports several times and still can't grasp the magnitude of it. All I know is, it's on a par with Einsteins theories and for that reason the BBC news team should try to be less comical in their 'mickey' taking reporting as this is a groundbreaking day for human achievement. Seeing Higgs in person on screen is like viewing Einstein itself. History in the making.

  • rate this
    +6

    Comment number 161.

    "Richard
    Can anyone explain how a particle which is 130 times the mass of a proton could be so elusive and remain undetected for so long?"

    Because you need extremely high energies (remember E=mc**2) to produce the conditions to reveal particles of that mass which promptly decay into other particles. It is measuring these other particles that show if they have been successful or not.

  • rate this
    +20

    Comment number 160.

    Great result.

    It's unfortunate that so many ingnoramuses object to the money spent just because they can see no immediate benefits of the discovery.

    The advancement of science virtually always produces something of benefit somewhere down the line, often in seemingly unrelated areas.

    If not for previous discoveries in particle physics we'd have no x-ray machines, MRI scanners etc.

  • rate this
    +16

    Comment number 159.

    In the grand scheme of human endeavour, this is a far bigger story than what some silly banker's been getting up to. Understanding how matter and energy work is fundamental to our search for totally clean, unobtrusive, virtually limitless energy sources. We're still many strides away from that, but this is very much in the 'giant leap for mankind' category.

  • rate this
    +82

    Comment number 158.

    Just to repeat for those who don't see the point of science. We are having this discussion over the Internet. The Internet was invented by Tim Berners Lee at CERN. I could go on, but I have to read my emails..

  • rate this
    +8

    Comment number 157.

    8.David Kelly
    I cannot see the point of spending Billions on this!!

    This advances knowledge.
    There may be many ethically "better" things to spend this money on but do you really think it would be used there if not on this??
    Its better than spending it on banks and bonuses, warfare, secret police, tax cuts for the rich, presidential mansions, ID databases, internet monitoring and much more.

  • rate this
    +7

    Comment number 156.

    Well done all, what a great achievment.

    Proud of my friend was working on the experimental data analysis team.

    Well done Michelle from Cumnock!

  • rate this
    +4

    Comment number 155.

    I think confirming a particle which underpins or begins to explain the mechanisms behind mass, and therefore having ramifications for ideas of gravity, and how the universe actually works etc is actually rather obviously useful for the future.

    Try looking up higgs boson on wikipedia before you comment on how useful it is or isnt

    Besides 2015 is when the hover cars are supposed to be here right?

  • rate this
    -19

    Comment number 154.

    Ok so there may be some benefits? but you don`t know? Many scientific discoveries are accidental, correct? many are subsequently discredited, Correct? and many may end up like the glue on a post it note! useful but not exactly going to change the world! while you stroke your beards, I bet theres an an "Oppenheimer" out there looking at its possibilities!

  • rate this
    +1

    Comment number 153.

    Hmmmm...it could be all tosh but then again....?
    10 billion expenditure is probably worth it as there will be genuine technological advances made through the life of the project, bosun or not

  • rate this
    +6

    Comment number 152.

    I hope the UK new coin designs will have this on the one pound coin?

  • rate this
    +15

    Comment number 151.

    "And the point is?"

    Are you suggesting that discovering what the world around of is made of is a waste of time?
    Luddites didn't see the point of Special Relativity either, but your phone wouldn't be working without it! The closest we have got to solving the energy crisis (fusion research and fission) is via particle research. How do we solve the world's problems if not with scientific innovation?

  • rate this
    0

    Comment number 150.

    Tremendous disovery. Certainly more value for money than the TV licence fee.

  • rate this
    -66

    Comment number 149.

    penguin337
    16 Minutes ago...... -17

    LOL. Thanks guys
    I'm overwhelmed by your opinion of the laymen who bankrolled this scalextic set for particles

    Now all you have to do is link the Higgs Boson to global warming and you've got government funding for life

    Instead of focussing on the easy lazy option, intellectual bullying, is there even ONE of your lot smart enough to explain it in simple terms?

  • rate this
    +17

    Comment number 148.

    The ignorance of the negative comments here is astounding.

    For example, something being more massive is not the same as it being "bigger". We need to spend more on science, not less. Discovering the fabric of all existence should be at the forefront of society so that we have more evidence on which to base development of our society.

  • rate this
    +8

    Comment number 147.

    I dont profess to understand it that well, but it is progress and that should be applauded. What are we if we do not strive to better ourselves.

  • rate this
    +325

    Comment number 146.

    Is there a better example of what we as human beings can achieve than this? A cost £2.6bn to build. 111 nations working together (for once) for over 10 years. 10,000 scientists and engineers combining their ideas, knowledge and skills. I'm quite proud to be a human being today and I don't often say that.

 

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