It may not possess the sense of overwhelming grandeur that CERN can muster, but Fermilab’s new 800km long neutrino experiment is just as ambitious. Leveraging the most powerful accelerator-based neutrino experiment ever built in the United States, researchers hope to unravel subatomic secrets and, through them, discover why the universe didn’t collapse back in upon itself immediately after the Big Bang.
The experiment is known as NOvA or NuMI Off-Axis νeAppearance, NuMI being Fermilab’s Neutrinos at the Main Injector — the fancy name for the lab’s gigantor 400kW particle beam. Crews have spent the last five years constructing the 800km-apart facilities at Fermilab in Batavia, Il and Fall Ash in northern Minnesota. The NuMI will blast protons straight through the Earth’s crust between the two locations where enormous detectors will sit at either end and monitor how the neutrinos change during their lightspeed transit.
The Near Detector in Illinois weighs 272 tonnes, the Fall Ash Far Detector tips the scales at a whopping 12,700 tonnes. In fact, at 60m long, 15m high and 15m wide, the Far Detector is considered to be the largest free-standing plastic structure ever constructed.
The data collected from the detectors will be analysed to generate 3D images of the neutrino activity. Picture: Lucas Taylor
The nuts and bolts behind the experiment involves some hardcore quantum physics theory but basically the researchers want to observe the oscillation of muon neutrinos to electron neutrinos. Neutrinos come in three varieties — muon, electron and tau — but over long distances they have been observed switching types. That is, a muon neutrino on one end of this experiment might be measured to be an electron neutrino at the other end. It’s that behaviour that Fermilab researchers hope to study.
This quirk of subatomics could have huge implications for our understanding of the universe, specifically how the current inequality between matter and antimatter came to be. Answering that could, in turn, provide a better insight as to why reality did not simply blink out of existence immediately after the Big Bang as a universe’s worth of matter and antimatter negated one another’s existences. [Fermilab 1, 2 – Wiki – Symmetry – Daily Galaxy]