Deep under a mountain in Italy, researchers continue to push the boundaries of science with an experiment that could rewrite the Standard Model of Particle Physics.
Their experiment, known as the Cryogenic Underground Observatory for Rare Events (CUORE), which includes researchers from Yale, has now collected two ton-years of data (the equivalent of collecting data for two years if the cube-shaped crystals in the CUORE detector weighed one ton) in a years-long effort to document a theory of rare nuclear particle decay called "neutrinoless double beta decay."
Standard "double beta decay" is already a proven particle process. When it occurs, two neutrons, which are uncharged particles in the nucleus of an atom, transform into two protons and emit two electrons and two antineutrinos. Antineutrinos are the antimatter counterpart to neutrinos.
Neutrinoless double-beta decay is a theorized process in which no antineutrinos are created. According to the theory, this would prove that neutrinos and antineutrinos are the same - that a neutrino is its own antiparticle.
In a new study in the journal Science, CUORE researchers used their latest dataset to place new limits on how often neutrinoless double beta decay occurs in an atom of tellurium. They say it occurs no more than once every 50 septillion years - or once every trillion trillion years.
Aiding the researchers' work was a specially designed algorithm that filtered out extraneous "noise" - i.e., vibrations, including the muffled sounds of researchers talking nearby, ocean waves hitting the Italian coast, and earthquakes sending out seismic shockwaves anywhere in the world. Think noise-cancelling headphones, but on a much larger scale.
"The focus of this data release is understanding sources of external vibrations and learning how to subtract that from our data to better search for this extremely rare decay," said Reina Maruyama, a professor of physics and astronomy in the Yale Faculty of Arts and Sciences (FAS) and CUORE member.
