AMoRE in South Korea finds no evidence of decay
The AMoRE experiment in South Korea has not found evidence of a rare process called neutrinoless double beta decay. This search lasted two years and has put strict limits on the behavior of neutrinos, mysterious particles that are very difficult to detect. Neutrinos are incredibly abundant in the universe. They were created during the Big Bang and are produced in various natural processes, including nuclear reactions in the sun. Scientists study neutrinos because they may help answer many important questions about the universe. However, the individual masses of neutrinos remain unknown. Neutrinos can come in three types, but their specific weights are still a mystery. If neutrinos are found to be Majorana particles, a type of particle that is its own anti-particle, it would provide insight into their properties. The process of neutrinoless double beta decay could reveal these masses, but it is extremely rare. In double beta decay, two neutrons in a nucleus convert to protons, releasing electrons and anti-neutrinos. In the hypothesized neutrinoless variant, only electrons are emitted, indicating that the neutrinos and anti-neutrinos are the same. The AMoRE experiment attempted to detect this process using special detectors and a sample of molybdenum-100 nuclei. On February 27, the AMoRE team published results showing they did not observe this rare decay process. They suggested that if it does exist, it might take more than 1,000,000,000,000,000,000,000,000 years to happen in their current setup. They plan to conduct further experiments with a larger sample of molybdenum-100 nuclei. Additionally, the team estimated that neutrinos must weigh less than a small fraction of a proton. This finding challenges existing theories of particle physics, which suggest neutrinos should have no mass at all. The AMoRE collaboration is looking forward to advancing its research in future experiments.