CERN May Have Found The Higgs Boson

Hilbert writes: "Scientists working at the LEP collider at CERN believe they have found evidence of the existance of the Higgs boson, one of the more elusive particles under investigation. BBC's got the story." Ironically, this important discovery (or possible discovery) comes weeks before the collider used to make it is scheduled to be shut down. Can you say "the dilemma of prior investment"?

Comments

Not shutdown, replaced

[Anonymous Coward]

As far as I know (I am a student in CS at the ETH in Zurich and my Physics prof works at the Cern) the LEP is shutdown because it is being replaced by a new collider, the LHC (Large Hadron Collider) in the next few years. Browseing through my notes I found a little chart.

Beams Energy Luminosity
LEPe+ e- 200 GeV10^32cm^-2 s^-1
LHCp p 14 TeV10^34
Pb Pb1312 TeV10^27


So in the end, the new Large Hadron Collider can accelerate those little bugger's up to much higher energies, thus probably alloweing other new particles to be observed (or confirmed) Oh and by the way, the Cern's at www.cern.ch See ya

One Page explanations

[nihilogos]

in 1993 the British Minister for Science challenged particle physicists to explain in one page or less what the Higgs Boson was and why they were so eager to find it.

http://hepwww.ph.qmw.ac.uk/epp/higgs.html

Re:I don't understand one bit.

[fiziko]

I can try. :)

About 30 years ago, particle physicists were trying to explain the way the world worked. Murray Gell-Mann and others developed a basic mathematical structure that could explain why people kept seeing all sorts of new particles every time they went looking. First, there was the electron and the proton. Then, Chadwick found the neutron (in 1932, I think), and the numbers kept growing. Soon, there were hundreds of so-called "elementary" particles and their antiparticles, and that was just more than anybody wanted to deal with.

Gell-Mann, Feynman, and several others soon realized that these could all be brozen down into about a dozen "elementary" particles, if you assumed that some of the ones we were seeing weren't actually elementary, but were actually composed of a small set of other particles, which Gell-Mann named quarks. They found a set of rules that could be applied to the way quarks combined (for the inclined: it's group theory, specifically the SU(3) group) that predicted which particles should exist, and which particles they could decay into.

The theory lacked one thing: an explanation for why things have mass. They could prove the theory worked in many cases, but in certain processes, the predictions for the probability of certain reactions happening were infinite. (Anything outside the range from 0 to 1 is impossible.) This made them very nervous, and was a rather large problem.

Higgs made a suggestion that worked. If there was another particle, which came to be known as the Higgs particle, then there would be other terms in the equation, which exactly matched the existing terms, apart from a negative sign. These extra terms correspond to the mass of a particle, which is why it's said that the Higgs boson is responsible for giving things mass. With this inclusion to the theory, the predictions began to match what was seen in the lab. The only thing that was missing was the Higgs Boson.

There have been various theoretical limits placed on the mass of the Higgs. It's massive enough to be hard to find, but just barely within the reach of some of the current accelerators, such as Fermilab and the LEP. The results reported at CERN may or may not be part of the random background events. Currently, the LEP is supposed ot shut down in late October/early November to make way for the LHC, the new, high-energy collider that should be able to find the Higgs boson, assuming the theories are correct. (Most of the LEP physicists have jobs on the LHC, so those of you writing this off as a reaction to unemployment just don't have all the relevant information.)

Anyway, all the experiments are saying is that the events they've seen may or may not be the evidence needed to support the only theory we have that predicts mass. They need to take another month of data to know for sure.

Re:Making Sense

[marat]

This is nice view for popular paper article but it would lead you in trouble if you're really trying to understand something or work in the area. For instance it's easy to imagine repulsion forces as a result of exchanging some particles, but it's impossible to explain attraction that way.

Actually there are no particles during interaction. Particle is an abstraction. Sea of particles is an abstraction. Even single field is an abstraction, but it is proper math object and we should have some starting point anyway. So while talking about discovering Higgs particle we actually mean discovering Higgs boson field. This field interacts with other fields so, that this fields behave like having mass. This is because of some math and there's nothing more about it.

And don't compare mass and weight here: while we believe in General Theory of Relativity, object weight and object resistance to accelerate (mass) is the same thing.
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Every secretary using MSWord wastes enough resources

Nothing ironic

[Camelot]

Prior investment ? The fact is that the LEP accelerator is being used for more that it was intended for. The maximum energy for the collisions was planned to be around 100 GeV, and the collider was supposed to be dismantled _last year_ (or maybe even before that). But, alas, they wanted to squeeze every useful bit out of LEP - hit the metal, use it to the max - the energies have been around 200 GeV this summer. After this the collider goes to the trash can.

The reason for all this is, of course, the desperate search for the Higgs particle. Now they *might* have evidence for it - thats great. Whether or not they have found it, the LEP has proved to be worth of the investment.

The reason for the dismantling of LEP is that they want to start installing the parts for the forthcoming LHC accelerator (that will collide protons and anti-protons) - which is due to start operation in 2005, so its not like they are retiring LEP for no reason at all.