FermiLab’s Mystery Signal Appears Real –Has It Discovered a New Force of Nature that will Revolutionize Our View of the Universe?


Physicists of the world are getting excited about the news of a possible particle sighting in the debris of proton-antiproton collisions at the Illinois accelerator that showed an unexpected rise in the number of events clustered around 145 GeV – suggesting that they are being produced by an unidentified particle of the same mass. It was immediately certain that whatever the particle was, it was not predicted by the standard model of physics, the leading theory for how particles and forces interact. To add to the mystery, it was clearly not a Higgs boson, the long-sought particle that gives other particles their mass eagerly being pursued at CERN's Large Hadron Collider outside Geneva.

Excitement is based on an analysis of eight years of data collected by Fermilab's CDF experiment that looked at collisions that produced a W boson, carrier of the weak nuclear force, along with two jets of quarks

The CDF team has analysed nearly twice the amount of data the first result was based on, and the result has not gone away. In fact, as CDF physicist Giovanni Punzi told a conference this week in Blois, France, the signal has only gotten stronger. It is reportedly at 4.8 sigma, tantalisingly close to five-sigma certainty needed to be considered "evidence" but still far from the five-sigma gold standard needed to proclaim a true epic discovery.  There is a 1 in 1 million chance that it was just a statistical fluke

 "We're still going through all the data, and we've got two other teams repeating the analysis in a different way, so we're not going to publish a five-sigma result until all of our i's and t's are dotted and crossed," says CDF spokesperson Rob Roser.

An independent peer review will also come from Fermilab's DZero experiment, which has enough of its own data to corroborate or cast doubt on the particle's existence, and is expected to publish its results in the next few weeks.

The Large Hadron Collider in Switzerland should also be able to test CDF's result. There's talk that the LHC hasn't seen any such bump – but Roser says that doesn't mean much one way or the other, as the LHC hasn't collected as much data as Fermilab. "They haven't really achieved the sensitivity to see this yet," he explains.

Some experts believe that the mystery force it's a particle called the Z-prime, a hypothetical carrier of a new force similar to the electroweak force, though it would have to be an unusual version of a Z-prime to have slipped by unnoticed at CERN's LEP collider.

Other physicists say it might be a sign of supersymmetry – that postulates that every particle has a shadowy partner. The Fermilab bump could therefore be pairs of "squarks" or "selectrons" – supersymmetric partners of quarks and electrons.

Another, even more esoteric theory posits that it is a technipion – a particle that appears in a theory known as technicolour, which posits a new force that is similar to the strong nuclear force but operates at much higher energies.

These are exciting times in decoding the foundational secrets of the universe we live in.

The Daily Galaxy via FermiLab and newscientist.com

Image top of page is a "charmed quark."


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