Let us go straight to read how the thing was reported in some online resources (boldface is mine).
``Physicists at the Fermi National Accelerator Laboratory are planning to announce Wednesday that they have found a suspicious bump in their data that could be evidence of a new elementary particle or even, some say, a new force of nature.
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The experimenters estimate that there is a less than a quarter of 1 percent chance their bump is a statistical fluctuation''
``Wednesday afternoon, the CDF collaboration announced that it has evidence of a peak in a specific sample of its data. The peak is an excess of particle collision events that produce a W boson accompanied by two hadronic jets. This peak showed up in a mass region where we did not expect one.
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The significance of this excess was determined to be 3.2 sigma, after accounting for the effect of systematic uncertainties. This means that there is less than a 1 in 1375 chance that the effect is mimicked by a statistical fluctuation.''
``If you're a little hazy about the details of Wednesday's buzz surrounding the potential discovery of "new physics" in Fermilab's Tevatron particle accelerator, don't worry, you're not alone. This is a big week for particle physicists, and even they will be having many sleepless nights over the coming months trying to grasp what it all means.
That's what happens when physicists come forward, with observational evidence, of what they believe represents something we've never seen before. Even bigger than that: something we never even expected to see.
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It is what is known as a "three-sigma event," and this refers to the statistical certainty of a given result. In this case, this result has a 99.7 percent chance of being correct (and a 0.3 percent chance of being wrong).''
``The last and greatest breakthrough from a fantastic machine, or a false alarm on the frontiers of physics?
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If the histograms and data are exactly right, the paper quotes a one-in-ten-thousand (0.0001) chance that this bump is a fluke.''
Giulio D'Agostini 2012-01-02