The Mysterious Origins of the Most Energetic Neutrino Ever Detected

In February 2023, a cosmic particle detector housed deep within the Mediterranean Sea recorded the arrival of a neutrino with roughly 20 to 30 occasions extra vitality than another neutrino documented beforehand. Labelled KM3-230213A, the particle had a calculated vitality of 220 petaelectronvolts (PeV), far better than the ten PeV of the beforehand most energetic neutrino. The discovering generated a variety of pleasure amongst physicists, however raised additionally many questions.Neutrinos are probably the most plentiful particles within the universe with mass. They’re a kind of basic particle, which suggests they don’t break down into smaller constituents, and are subsequently very small and light-weight. In actual fact, they’re the lightest of all subatomic particles which have mass. Neutrinos additionally don’t have a cost (in contrast to, say, electrons, one other sort of basic particle, that are damaging). Because of this, solely very hardly ever do neutrinos work together with with different matter; typically they’ll cross straight by it with out altering it. In actual fact, trillions of neutrinos travelling by house could have handed by your physique because you began studying this text. Because of this neutrinos typically known as “ghost particles.”For particle physicists, the detection of this anomalously energetic neutrino may solely be defined in two methods: Both KM3-230213A was proof of a cosmic course of, probably one by no means witnessed earlier than, with the potential to vary our understanding of neutrinos; or it was a disappointing measurement error. Researchers shortly set to work to seek out out which clarification was true.Now there appears to be a solution. A complete examine printed within the journal Bodily Evaluate X in contrast the info of KM3-230213A with databases of data on different ghost particles which were detected. Having analyzed the accessible knowledge, scientists consider that this outstanding, ultra-energetic neutrino was not a statistical phantasm.However The place Did It Come From?Simply as a rock can not describe the character of a mountain, a 220 PeV neutrino alone isn’t helpful in explaining the phenomenon that gave rise to it. Because the paper acknowledges, with the data accessible, it’s not attainable to “draw agency conclusions on whether or not the commentary hints at a brand new ultra-high-energy part within the spectrum.”But when there have been different recordings of equally energetic neutrinos, this might current a considerable advance by hinting that different beforehand unseen phenomena are on the market. “It may imply we’re seeing cosmogenic neutrinos for the primary time, produced when cosmic rays interacted with the cosmic microwave background, or it may level to a brand new form of astrophysical supply,” the examine says.The vitality of the 2023 neutrino additionally suggests it may have been emitted by one of many highly effective cosmic accelerators that we’re conscious of within the universe: a gamma-ray burst or supernova, or maybe a relativistic jet—a beam of plasma emitted from the neighborhood of a black gap. In distinction, lots of the neutrinos detected on Earth are atmospheric neutrinos, produced by the influence of cosmic rays hitting atoms in Earth’s ambiance, and are far much less energetic. They’re the identical particles, however their probably origins influence their vitality.Completely different branches of science use and examine neutrinos for various causes. As a result of neutrinos journey by the universe with out being deflected or absorbed, they’ll present precious details about very distant cosmic occasions. Some scientists consider them as “reporters from the universe” who, sometimes, journey to Earth with knowledge that might in any other case be misplaced.This story initially appeared on WIRED en Español and has been translated from Spanish.