Beauty quarks or B mesons particles are not decaying as they should and while the findings may warrant “cautious excitement”, more research needs to be done, scientists say.
CERN, The European Organization for Nuclear Research, has announced a new discovery that may change the way we think about physics.
CERN is an international laboratory whose work "helps to uncover what the universe is made of and how it works."
According to an article in the Guardian, “scientists at the Large Hadron Collider near Geneva have spotted an unusual signal in their data that may be the first hint of a new kind of physics.”
The LHC has four main teams working on it. The LHCb (Large Hadron Collider beauty) collaboration has analysed 10 years of data on B mesons. B mesons are unstable particles that are momentarily created in the LHC and “decay into familiar material such as electrons”.
The Standard Model of particle physics is what the BBC calls “the best theory we have to explain the fine-scale workings of the world around us” while admitting that the SM is “a stepping stone to a more complete understanding of the cosmos.”
Deviation from standard model?
Mitesh Patel, of Imperial College London, told BBC News: "We were actually shaking when we first looked at the results, we were that excited. Our hearts did beat a bit faster."
"It's too early to say if this genuinely is a deviation from the Standard Model but the potential implications are such that these results are the most exciting thing I've done in 20 years in the field. It has been a long journey to get here."
The Standard Model suggests that the particles should break down into products that include electrons “at exactly the same rate as they do into products that include a heavier cousin of the electron, called a muon”, the Guardian report says.
Yet in the LHCb experiment, that didn’t happen – it turned out that the end result was more electrons than muons. The Guardian writes: “Instead of producing electrons and muons at the same rate, nature appears to favour the route that ends with electrons.”
According to BBC News, “the LHCb produces sub-atomic particles called "beauty quarks", which are not usually found in nature …Sub-atomic particles undergo a process known as decay, where one particle transforms into several, less massive ones.”
The standard model foresees that “beauty quarks should decay into equal numbers of electron and muon particles. Instead, the process yields more electrons than muons.
One possible explanation is that an as-yet undiscovered particle known as a leptoquark was involved in the decay process and made it easier to produce electrons.”
“We would expect this particle to decay into the final state containing electrons and the final state containing muons at the same rate as each other,” said Prof Chris Parkes, spokesperson for the LHCb collaboration and an experimental particle physicist at the University of Manchester. “What we have is an intriguing hint that maybe these two processes don’t happen at the same rate, but it’s not conclusive.”
In order for particle physicists to announce a new discovery, a result is expected to reach a significance of five sigma. What that means is “the chance of it being a statistical quirk are reduced to one in a few million.”
The LHCb experiment result has a significance of 3.1 sigma, which is why scientists are more cautious about celebrating it. That means the chance of the result being a fluke is about one in 1,000.
“It’s an intriguing hint, but we have seen sigmas come and go before. It happens surprisingly frequently,” Parkes said.
The standard model of particle physics, that was explained over the past half-century, does not account for everything in the physics world. For example, while it explains three out of four fundamental forces of nature, it falls short of describing gravity, and “says nothing about the 95 percent of the universe that physicists believe is not constructed from normal matter.”
According to the report, scientists believe much of the cosmos consists of dark energy, “a force that appears to be driving the expansion of the universe” and dark matter, “a mysterious substance that seems to hold the cosmic web of matter in place like an invisible skeleton.”
“If it turns out, with extra analysis of additional processes, that we were able to confirm this, it would be extremely exciting,” Parkes said. It would mean there is something wrong with the standard model and that we require something extra in our fundamental theory of particle physics to explain how this would happen.”
Parkes said that while there is still uncertainty over the result from the LHCb experiment, physicists are “cautiously” excited about developments about this and other results on B mesons.
“I would say there is cautious excitement. We’re intrigued because not only is this result quite significant, it fits the pattern of some previous results from LHCb and other experiments worldwide,” he said.
Ben Allanach, a professor of theoretical physics at the University of Cambridge, is one scientist who finds the result exciting, especially when taken with other findings. “I really think this will turn into something,” he said.
If the result turns out to be true, it could be explained by so-far hypothetical particles called Z primes or leptoquarks that bring new forces to bear on other particles, the Guardian report says.
“There could be a new quantum force that makes the B mesons break up into muons at the wrong rate. It’s sticking them together and stopping them decaying into muons at the rate we’d expect,” Allanach said. “This force could help explain the peculiar pattern of different matter particles’ masses.”
“B mesons contain elementary particles called beauty quarks, also know as bottom quarks,”The Guardian explains.
According to The Guardian, scientists will collect more data from the LHC and other experiments around the world, such as Belle II in Japan, in the hope of confirming what is happening.