In the heart of a mountain in central Italy, there’s a new neutrino detector that hopes to answer one of the biggest questions in the universe: why is matter a lot more common than antimatter?
The Cryogenic Underground Observatory for Rare Events (CUORE) has been operating for just two months and researchers have now released their preliminary results on ArXiv and submitted them to the journal Physical Review Letters.
“This is the first preview of what an instrument this size is able to do,” said Oliviero Cremonesi, a senior faculty scientist at INFN and spokesperson for the CUORE collaboration, in a statement.
The instrument comprises 19 copper cases each hosting 52 tellurium dioxide cubes and is cooled down to just 10 milliKelvins. CUORE is an incredibly sensitive thermometer. It needs the sensitivity to detect the rare events it's designed to find, like neutrinoless double beta decay. The latest result suggests that in a single atom this would only happen once every 100 septillion (1 followed by 26 zeros) years. Since we don’t have that kind of time, the detectors need to be extremely large.
If neutrinoless double beta decay exists, it means that neutrinos are their own antiparticles. While it's not an unheard property in physics (the Higgs Boson is its own antiparticle too), if this is the case for neutrinos, it means that a property known as the conservation of lepton number is violated. That would actually explain why the universe is made of matter and not antimatter.
The opposite case would also be exciting. If neutrinos aren't their own antiparticles, it means we have missed two types of neutrinos in all our observations. The observations of CUORE could finally provide a definitive answer to this question.
“We are tantalizingly close to completely unexplored territory and there is great possibility for discovery. It is an exciting time to be on the experiment.” Lindley Winslow of the Massachusetts Institute of Technology, who coordinated the analysis of the CUORE data, said.
CUORE, which means heart in Italian, is located within the Gran Sasso, the tallest mountain in the Appennini chain. The collaboration has 150 members from 25 international institutions.