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 higher than the ten PeV of the beforehand most energetic neutrino. The discovering generated numerous pleasure amongst physicists, however raised additionally many questions.
Neutrinos are the most considerable particles within the universe with mass. They’re a sort of elementary particle, which suggests they don’t break down into smaller constituents, and are due to this fact very small and lightweight. Actually, 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 kind of elementary particle, that are destructive). Consequently, solely very not often do neutrinos work together with with different matter; typically they’ll cross straight by means of it with out altering it. Actually, trillions of neutrinos travelling by means of house may have handed by means of your physique because you began studying this text. For that reason neutrinos generally referred to as “ghost particles.”
For particle physicists, the detection of this anomalously energetic neutrino might 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 alter our understanding of neutrinos; or it was a disappointing measurement error. Researchers rapidly set to work to search out out which clarification was true.
Now there appears to be a solution. A complete research revealed within the journal Bodily Evaluation X in contrast the info of KM3-230213A with databases of knowledge on different ghost particles which were detected. Having analyzed the obtainable 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 knowledge obtainable, it’s not potential to “draw agency conclusions on whether or not the remark 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 might imply we’re seeing cosmogenic neutrinos for the primary time, produced when cosmic rays interacted with the cosmic microwave background, or it might level to a brand new type of astrophysical supply,” the research says.
The vitality of the 2023 neutrino additionally suggests it might 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, most 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 seemingly origins influence their vitality.
Totally different branches of science use and research neutrinos for various causes. As a result of neutrinos journey by means of the universe with out being deflected or absorbed, they’ll present helpful details about very distant cosmic occasions. Some scientists consider them as “reporters from the universe” who, occasionally, journey to Earth with knowledge that will in any other case be misplaced.
This story initially appeared on WIRED en Español and has been translated from Spanish.
