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topicnews · September 30, 2024

Scientists have just discovered a 1 in 10 billion quantum physics phenomenon

Scientists have just discovered a 1 in 10 billion quantum physics phenomenon

  • When protons collide with a beryllium target in CERN’s Super Proton Synchrotron (SPS), the resulting subatomic chaos creates a few kaons – a type of subatomic particle.
  • Physicists predict that about one in ten billion of these kaons will decay into a positively charged pion, a neutrino/antineutrino pair. And now they have successfully discovered it.
  • This particular decay is a suitable candidate for the discovery of completely new particle physics.

Quarks are strange. These subatomic particles are the building blocks of all matter and tend to transform completely into different things when subjected to incredible collisions in a particle accelerator. In about six percent of cases, this recombination results in a kaon, a different Kind of subatomic particle.

This is where things start to get weird. About one in ten billion Sometimes a positively charged kaon decays into a positively charged pion and a neutrino-antineutrino pair. Although these experiments produce nearly a billion secondary particles every second, it takes a very long time to find the single exception to what appears to be a rule of our current understanding of the Standard Model of physics. Well, physicists who are Part of the NA62 collaboration– a group dedicated to studying rare kaon decays – announced at a CERN seminar that their team had successfully documented this “decay of extremely rare particles.”

“This observation is the culmination of a project that began more than a decade ago,” said Giuseppe Ruggiero, a researcher at NA62. said in a press release. “Looking for effects in nature whose probability of occurrence is in the order of 10-11 is both fascinating and challenging. After rigorous and careful work, we finally saw the process that NA62 was designed and built to observe.”

To create these kaons you need highly specialized equipment. In particular, you need the Super Proton Synchrotron (SPS) – the second largest machine in the CERN accelerator complex (of course, the second largest after the Large Hadron Collider). The SPS fires a stream of high-energy protons at a beryllium target, producing a secondary beam that is only six percent kaons. The particles enter a vacuum tank, where a silicon pixel detector measures the resulting subatomic chaos.

Studying kaons – and in particular this specific decay behavior – is crucial to our understanding of physics because, according to the researchers, they are “extremely sensitive to deviations from the Standard Model prediction.” This makes kaon-to-pion and neutrino-antineutrino decay one of the few areas where new particle physics could be discovered. Although the researchers say their results are 50 percent larger than the Standard Model predicts, the measurements are potentially accurate because they lie within the range of uncertainty.

“The search for clues to new physics in this decay requires more data, but this result is a leap forward and further strengthens the strong interest in this line of research,” said Karim Massri, NA62 physics coordinator, in a press release.

This pion-neutrino pair decay was predicted by the Standard Model and technically even detected before, but this is the first time the team has measured the event with a statistical significance of just five standard deviations (measured in sigma). The higher the sigma, the less likely the detection is a coincidence or glitch and the more likely the hypothesis is true. Crossing the five sigma threshold usually means a discovery – the discovery of the Higgs boson, for example, was not announced until a reading with statistical significance above five sigma was captured.

Now that physicists have confirmed this event and the confirmation has been deemed statistically significant, they can now move forward and investigate the unknown properties of this extremely rare event.

“The point of this measurement is to identify the K+ decay that is one in ten billion and represents our signal, and to ensure that it is not one of the other 9,999,999,999 decays that can mimic the signal,” said Joel Swallow, lead data analyst for the project, in a press release. “The entire collaboration with NA62 made this almost impossible result possible.”

Darren lives in Portland, has a cat, and writes/edits about science fiction and how our world works. If you look closely, you can find his previous stuff at Gizmodo and Paste.

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