About four years ago, a team of Hungarian physicists at the Institute for Nuclear Research noticed something strange in their experiments with beryllium-8, an excited radioactive isotope that emits photons as it decays.
According to the standard model of physics, if any one of the photons has high enough energy, it can transform into an electron and a positron. The particle pair is supposed to part way at an angle of 180 degrees. But in their study, scientists had consistently observed an angle of 140 degrees instead.
This year the same group discovered a second example in which the bizarre phenomenon showed up. They theorized that a previously unknown particle (likely an undiscovered boson), which they named X17, could be behind the anomaly.
If this discovery can be confirmed by other groups and using different methodologies, scientists suggested that X17 could be an indication for the existence of a fifth fundamental force of nature, on top of the gravitational and electromagnetic interactions, and the strong and weak nuclear forces. Some even suggest that it could also help solve the dark matter problem.
While many are excited about the news, others cautioned that we should not be celebrating just yet. A single unverified result does not mean that we have a scientific breakthrough. History does not lack examples that proclaimed game-changing discoveries turned out to be results of errors in machineries, measurements, or interpretation after all.
Scientists at CERN's NA64 collaboration have also joined the searches for X17 using their Super Proton Synchrotron accelerator. They hypothesized that if X17 does exist, they would observe an electron-positron pair during the bombardment of target materials with a high-energy electron beam. But so far, the collaboration hasn't found anything yet. Only time will tell whether we are looking at a true breakthrough in science or not.
The Hungarian scientists published their latest study on the pre-print server arXiv.
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