Detected for the first time in 2006, these strange particles defying the laws of physics fascinate scientists, who aim to discover their exact nature and origin in the years to come.
Very strange signals
Three times since 2006, the system ANITA (Transient Pulse Antenna of Antarctica), a floating balloon with a particle sensor, recorded a strange signal seeming to demonstrate the existence of high energy particles. These seem to emanate from the ice cap and seem capable of spreading smoothly across the planet. Accessible from the pre-publication server arXiv, these new works exclude the hypothesis considered so far as the most probable, which implies that our current understanding of physics may be insufficient to explain their nature.
Previously, scientists believed that these particles were neutrinos, known for their ability to cross other materials, but according to the standard model of particle physics, the incredibly high energy levels of these tiny particles (a billion billion electronvolts) recorded by ANITA Normally should have implied that they interact with those present inside the Earth, and not that they cross thousands of kilometers of rock, magma and iron as easily.
So that a neutrino at high energy could emerge unscathed from such a crossing, this would imply that the latter comes from a distant cosmic source (neutron star, galaxy…) capable of accelerating the neutrinos and sending them back into space.
A persistent mystery despite the numerous analyzes carried out
Assuming it was indeed a cosmic source, researchers at theuniversity of Wisconsin-Madison ((United States), working atObservatory neutrinos IceCube ((Antarctic), studied the data they had collected over the years in search of signals similar to those detected by ANITA, but these gave nothing. It is therefore likely thatANITA has identified a sign of exotic physics or that it is a subtle measurement error, which all researchers would have neglected.
Physicists are now counting on an update of the device data in which will be described all the abnormal events that occurred during a last flight of the balloon in 2016, which could provide major information about other high energy detections and help them solve this mystery.
Pending these results, there is no shortage of theories about the true nature of these enigmatic particles, which may question the standard model. Some researchers believe it could be stau neutrinos, supporting the theory of ” supersymmetry That all of the fundamental particles have much heavier counterparts. While others believe that the signals recorded could reveal the existence of black matter or from sterile neutrinos not interacting via any of the basic interactions of the standard model, except gravity.