#ÉclatsDeSciences | À la poursuite des neutrinos pour mieux comprendre l’univers
Une gigantesque expérience est en cours de construction dans des cavernes aux États-Unis. Objectif: mieux connaître les #neutrinos, des particules très furtives que les physiciens traquent depuis des décennies. Et comprendre, peut-être, deux des plus grands mystères de la #physique.
A New Observatory Will Spot Core-Collapse Supernovae Before they Explode
Although we haven't had a supernova explode nearby in a few hundred years, it's just a matter of time before it happens. Astronomers want to be ready. The Jiangmen Underground Neutrino Observatory is being built in China and should be gathering its first data by the end of 2023. If all goes well, it can detect a burst of neutrinos coming from a core-collapse supernova before we can see the flash of radiation. As the star is imploding, energy piles up inside the star, but the neutrinos can freely escape, arriving seconds earlier than the radiation. It'll have a range of 3,000 light-years for pre-supernova neutrino detections and 1.2 million light-years for post-supernova detection.
"… [German experiment KATRIN says neutrinos] have a small mass that could be either positive or negative mass squared. That means they could have, based on the way they do the experiment, an imaginary mass, which would make them “tachyonic neutrinos.” This would make them potentially travel faster than the speed of light or potentially backward in time …" — #outofcontext #neutrinos#tachyons#timetravel