Forget the Higgs, theres a new boson in town.At least, this is what is hinted at by the latest data coming from the Large Hadron Collider (LHC). The potential discovery has sent theoretical physicists into a frenzy, with nine papers explaining the data already uploaded onarXiv hours after the results were presented.
The LHC experiments ATLASand CMS have both detected a bump in the data from the events following the proton-proton collisions. Among the particles produced by the collisions, the experiments saw an excess of photonpairs; this is usually an indication that there is a new particle.
The bump was seen in 50 photon pairs (40 in ATLASand 10in CMS) and each pairhad an energy of 750 gigaelectronvolts (GeV). This indicates that the potential new particle is a boson (but not necessarily like the Higgs)and it hasa massequivalent to almost 800 protons. Physicists are intrigued as they werent expecting anything with that mass.
Although this is very exciting, there is a lot more to do before this hint is proven to be a particle or just a coincidence. The low number of detections corresponds to a low statisticalcertainty. The ATLASexperiment has a confidence level of 99.99 percent(3.9 sigmas) and CMS has a confidence level of 98.9 percent(2.6 sigmas). These values seem really high, but you can see them as onein 10,000 and a bit more than onein 100, respectively. You wouldnt get in a plane if those were the odds that it would come crashing down.
New particles can only be confirmed if the confidence level has reached 5 sigmas (99.9999 percent), meaningthe detection has only a one in 3.5 million chanceof being a fluke. The LHC has finished operations for the year, so reaching the 5 sigma level will be the goal of the machine in 2016.
Several theoretical explanations have been put forward to explain the potential new particle. From dark matter to string theorytosome exotic version of the standard model of physics, the explanations are squeezing anything possible from the limited data available.
However,the physicists working on ATLAS and CMS are being level-headed when it comes to the bump. Speaking to IFLScience, Professor Dave Charlton, spokespersonfor ATLAS,said: “It is too early yet to think that we are seeing anything more than a statistical fluctuation, which is not unlikely.”
He continued:”I would rather not speculate on what it might be, if it is not just a chance coincidence in the experiments, our job is rather to look hard at the data to see if there is more we can learn, and most especially to prepare for the new data samples coming next year. This is what we are doing!”
If these hints turn out to be a discovery, the world of particle physics might not be the same. The LHC will beback online in March and physicists expect 10 times as much data next year.”If there is an actual natural phenomenon behind these fluctuations, we will know,” Tiziano Camporesi, a CERN physicist and spokesperson for theCMS team, toldNature.
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