LHC: “we have observed a new particle consistent with a Higgs boson. But which one?”

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That’s what they’ll be trying to work out over the next few years.  Matt Strassler’s probably the man to go to for more on the options ahead.  But, for now, the news from Cern is that they have, almost certainly, found “that damned elusive particle“, a Higgs boson.  Earlier this morning one of the six theoreticians who predicted the field/boson, Peter Higgs, instructed his family to start chilling the champagne, and Stephen Hawking has conceded that he has lost his $100 bet.  As an aside, noted previously, here’s a fascinating Guardian interview with Peter Higgs from 2007.

From the BBC report

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.”

Here’s the moment of the announcement, via the Irish Times report.

And Cern’s John Ellis answers the question “What is the Higgs boson?”

The Guardian live-blog has now closed, but has lots of information and links.  Including this from Brian Cox

This is without doubt in my opinion the biggest scientific discovery of my lifetime and without doubt one of the biggest scientific discoveries of all time, so I’m tremendously excited… This day will go down as one of the great days in the history of science I think, and that’s not overly hyperbolic.

This is a prediction that was made almost 50 years ago. And the prediction is that the universe, everywhere, empty space, everywhere you look, every little cubic centimetre of space in front of you and inside your body and across the universe, is rammed full of Higgs particles, and everything that makes up your body, the little subatomic particles in your hand, are bouncing off them, and that’s how they get their mass.

And more than that the theory said that these Higgs particles condensed out into empty space less than a billionth of a second after the universe began. It sounds very esoteric and fundamental. But what we’ve shown today is that’s right. That’s actually how the universe works. So it’s one of the central planks of our understanding of how everything in the universe works.

And even though, throughout my whole career as a particle physicist of 20 years now, this theory has been there, I think the realisation that it’s actually right is quite shocking, actually; I’m quite shocked that such a strange thing has been shown to be true.

It’s also worth noting the quote from Stephen Hawking on his lost bet.

This is an important result and should guarantee Higgs the Nobel prize 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.

As I’ve mentioned before, here’s a good introduction to the Standard Model of Particle Physics from Cern News – it’s the first in a series of videos.

Of course, there may still be further wrinkles ahead…

Final point to note, again, from the earlier BBC report

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.”

2012 looks set to be a vintage year for particle physics”, indeed.

Adds Niall has a good background post on the announcement here.

And from the Guardian’s tame particle physicist, Jon Butterworth, who’s a member of the ATLAS team.

So today has been amazing. Today we saw a completely objective, repeatable, observation of something fundamentally new.

Say that again. Twice.

And it’s existence was predicted by mathematical understanding of previous data, coupled with some prejudices about aesthetics, symmetry and how a decent universe ought to hang together. I don’t know about you, but this amazes me.

Now, it looks like the Higgs boson. Or a Higgs boson. But it might not be. It has the right electric charge (i.e. none). It seems to appear about as often as it should in some decay modes. It is definitely a boson. But it is supposed to give mass to all fundamental particles, and we haven’t seen it do anything with fermions (quarks and leptons) yet, just bosons.

So it looks like a Higgs. But we need to look more carefully.

And there might be more of these things out there…

These are great times.

Indeed.

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  • salgado

    Fantastic news, and so far the LHC has only taken 1/3 of the data it expects to have by the end of the year. There’s still plenty of work to be done reconciling some of the different detection channels and narrowing down the properties.

    The current signal is more than (but consistent with) the signal expected from the standard model, so it will be particularly interesting to see which way that swings once they have more statistics.

    All in all, this should be a great couple of years for particle physics (ignoring the ongoing funding problems).

  • Pete Baker

    Adds Niall has a good background post on the announcement here.

  • Niall Fealty

    I like the reaction to this mornings news, really shows how important this all is.

    I also love the way John Ellis picked just about the best t-shirt for today!

  • sherdy

    The king’s new clothes? We’ll all be dead and gone before it can be proved or disproved. Maybe Its a conCern!

  • Pete Baker

    Ditto on the t-shirt, Niall.

    I want one.

  • Pete Baker

    And from the Guardian’s tame particle physicist, Jon Butterworth, who’s a member of the ATLAS team.

    So today has been amazing. Today we saw a completely objective, repeatable, observation of something fundamentally new.

    Say that again. Twice.

    And it’s existence was predicted by mathematical understanding of previous data, coupled with some prejudices about aesthetics, symmetry and how a decent universe ought to hang together. I don’t know about you, but this amazes me.

    Now, it looks like the Higgs boson. Or a Higgs boson. But it might not be. It has the right electric charge (i.e. none). It seems to appear about as often as it should in some decay modes. It is definitely a boson. But it is supposed to give mass to all fundamental particles, and we haven’t seen it do anything with fermions (quarks and leptons) yet, just bosons.

    So it looks like a Higgs. But we need to look more carefully.

    And there might be more of these things out there…

    These are great times.

    Indeed.

  • sonofstrongbow

    Now a handshake between the boson and a fermion that would be news.

  • Charlie Sheens PR guru

    I think this is really good. Although had the answer been ‘no, it doesn’t exist’ thatb too would be interesting as we’d need to rip up the textbooks and start again.

    One thing that disappoints me is the totemic importance that the Higg’s has gained in this whole discussion. Some people are under the impression that the LHC was built primarily to find this particle when in fact, this particle is probably the lowest hanging available fruit. Afterall, it was predicted and we knew more or less where to start looking…

    Its the things like dark matter, dark energy, super symmmetry (which I think had some cold water poured on it last year) and extra dimensions which will really astonish us as they unknown unknowns (dark energy) as well as known unknowns (Higg’s).

  • carl marks

    The Vatican has released a statement claiming the HB is a Catholic,
    “ without it there would be no mass”, it said.

  • carl marks

    Should I get my coat !

  • Mister_Joe

    guru,

    You do know that they have been searching for it since it was predicted by Prof. Higgs and his colleagues in 1964?

  • Charlie Sheens PR guru

    Carl Marks,

    Actually, in anticipation of that joke your coat has already left!

  • Charlie Sheens PR guru

    Mister_Joe,

    As a physicist I’m very aware of that.

    The point I’m making however is that the LHC has ploughed so much of it’s media capital into building up this discovery that they may put all their media profile eggs into one basket.

    Remebr there are a number of other detectors as well as ATLAS ans CMS at the LHC like LHCb which do not set out to learn about the HIgg’s but (in this case) antimatter. I for one am curious about why there is more matter (obviously) than antimatter but I don’t hear the discussion given any attention whatsoever.

  • Mister_Joe

    Sorry, guru, I didn’t know that you are a physicist.
    But today is Higgs day and deserves the attention/hype. I am much interested in all matters scientific, always have been, but, from my discussions with other people, most aren’t. They are much too busy with day to day concerns.

  • Charlie Sheens PR guru

    My apologies too Mister_Joe,

    I sound like I’ve just turned up here to rain on everyone’s parade,

    You’re right this is Higg’s day, and barring a miracle this will be confirmed beyond the doubt of any statistical aberration within a couple of years.

    Its precisely because I know ppl working at CERN at th eLHC is why I make the point about coverage. They work on, probably even tougher theoretical challenges and I do see their work somewhat ignored because they’re not doing the right sort of experiment for the media.

    I’d be happier to know that we will have this celebration of science everytime the LHC makes a discovery/rules out a theory!

  • Mister_Joe

    Yes, guru, an amazing organization. According to wiki, just under 2,400 full-time employees and hosts some 10,000 visiting scientists and engineers. Obviously not all involved in looking for the Higgs’ boson.

  • http://nicentreright.wordpress.com/ Seymour Major

    This is a great story and a great leap in scientific discovery and I hope that Higgs is now officially honoured swiftly, particularly in view of his age.

    As I thought about higgs bosons, I could not help wondering what the clerics would make of it. I think some of them will at least be annoyed by the nickname given to the Higgs Boson, “the God Particle.”

    A read through the first part of Genesis reveals the damage to creationism caused by previous scientific discoveries (not just evolution). Imagine the problem. You have night and day. You have a thing called a firmament to separate Heaven and Earth. You also have plants living on the Earth but the Sun, the moon and Stars do not get created until the fourth day. So, can the Higgs Boson do anything to alleviate the problem?

    Well, to a person with sufficient understanding, the established scientific story of the Cosmos is absolutely incompatible with the creation story. But hold on there. Not everybody understands physics like a well-educated scientist. If this Higgs Boson is what they say it is – a particle that gives rise to matter, surely with a bit of imagination a smart story can be made up to convince religious believers that the divine depoloyment of HBs and other qualifying sub-atomic particles in appropriate places will explain these apparently impossible happenings.

    Maybe a temporary fireball in the sky (which was not a star) was created using HBs and other particles to keep the plants alive. Maybe the HBs can turn up in all sorts of weird places and help to explain miracles.

  • Mister_Joe

    Seymour,

    I believe that some physicist called it “that goddamn elusive particle” and it was the “popular” press that shortened it to the God particle.

  • Pete Baker

    CS PR guru

    Its precisely because I know ppl working at CERN at th eLHC is why I make the point about coverage. They work on, probably even tougher theoretical challenges and I do see their work somewhat ignored because they’re not doing the right sort of experiment for the media.

    I’d be happier to know that we will have this celebration of science everytime the LHC makes a discovery/rules out a theory!

    When/if they do actually have a result then I’ll certainly try to give it suitable treatment on Slugger. Can’t promise any more than that.

    But this is the almost certain confirmation of a 50-plus year-old theory on which the Standard Model depends – further wrinkles not withstanding.

    As Jon Butterworth said,

    So today has been amazing. Today we saw a completely objective, repeatable, observation of something fundamentally new.

    Say that again. Twice.

    And it’s existence was predicted by mathematical understanding of previous data, coupled with some prejudices about aesthetics, symmetry and how a decent universe ought to hang together. I don’t know about you, but this amazes me.

  • Charlie Sheens PR guru

    Seymour Major,

    I think he probably will the honoured in the not too distant future.

    As for the “god particle” nickname and I never envisaged it creating a fuss until I once chatted about three years ago with an old school friend and he got the totally wrong end of the stick regarding its naming. He started to invoke a bit of theological hysteria about having this idea thrust on ppl and I had to tell him, in no uncertain terms, that it could have been nicknamed “the boss particle” or “the big cheese particle” but it might have lost some credibilty. It worried me that a fairly smart guy like him misinterpreted it so badly.

    As regards, to the clergy, having attended a catholic grammar I can say that most catholic priests and followers are not literalists and are in fact as delighted and absorbed by these discoveries as the rest of us.. indeed our head teacher was a mathematician at Cambridge before he decided to join the clergy.

    That said it will probably only create a small change in people’s thinking as those open to scientific challenge probably have done so by now and those who haven’t probably never will.

    You’re welcome to begin inventing your own biblical HB theories! Maybe there are more out there!

  • Pete Baker

    Mass, Seymour. Not matter.

    Joe, no. It’s advertising. Leon Lederman, a 1988 nobel winning physicist, and writer of a book on the Higgs boson coined the term.

    I did the reverse of your suggestion in a previous post.

    But I was prompted by Matt Strassler.

  • Mister_Joe

    Thanks, Pete, I love to learn something new everyday.
    Great lecturer. I’ll be playing the other excerpts a bit later (dinner time here).