Atucha 2 supports neutrino experiment
Atucha 2 is a 693 MWe pressurised heavy water reactor owned and operated by Nucleoelectrica Argentina SA (NA-SA) which has been in operation since 2014. Iván Sidelnik of the Bariloche Atomic Center said, "We chose Atucha II because it has more power and provides us with a suitable place very close to the reactor core."
Nuclear power plants have been used to study neutrinos before, but this is the first experiment to be sited within containment.
Neutrinos come from stars throughout the universe and so are present everywhere, but their very small mass and lack of electric charge means they hardly interact with matter and are therefore hard to detect and study. Nuclear reactors, however, produce neutrinos with every fission reaction and so represent a local and highly concentrated source of the harmless particles.
Sidelnik and other scientists of the vIOLETTA Project are using sensitive Skipper CCD equipment designed and prepared by Fermilab and Berkeley National Laboratory in the USA. Somewhat like a digital camera, these will be able to detect interactions between neutrinos and a silicon matrix. The experimental arrangement will give them insights on neutrinos at previously unexplored low energy ranges.
A complication for vIOLETTA is that the detector must be cooled to -230°C, even while it is within 12 metres of Atucha 2, which runs at about 300°C. It also needs to be shielded from the vibrations of the power plant's operation. While the equipment will be remotely monitored, Sidelnik said it will help to have Nucleoelectrica's trained technicians on-hand to provide support.
In September this year, a long-running neutrino experiment at China's Daya Bay and Ling Ao nuclear power plants was concluded. That had seen large detectors placed in shielded underground positions. By comparing results from two sets of detectors, scientists were able to learn more about the interactions between neutrinos that cause some of them to vanish.