“NOvA represents a new generation of neutrino experiments,” said Fermilab Director Nigel Lockyer. The 50-foot (15 m) tall detector blocks are filled with a liquid scintillator that’s made of 95% mineral oil and 5% liquid hydrocarbon called pseudocumene, which is toxic but “imperative to the neutrino-detecting process.” The mixture magnifies any light that hits it, allowing the neutrino strikes to be more easily detected and measured. Even though only a fraction of the experiment’s larger detector, called the far detector, is fully built, filled with scintillator and wired with electronics at this point, the experiment has already used it to record signals from its first neutrinos.” The two detectors of the NOvA experiment are placed so far apart to give the neutrinos the time to oscillate from one flavor to another while traveling at nearly the speed of light. In fact the beam, which starts out 150 feet (45 meters) below ground near Chicago, eventually passes over 6 miles (10 km) deep during its trip.Īccording to a press release from Fermilab, neutrinos “come in three types, called flavors (electron, muon, or tau), and change between them as they travel. The near detector at Fermilab confirms the initial “flavor” of neutrinos in the beam, and the much larger far detector then determines if the neutrinos have changed during their three-millisecond underground interstate journey.Īgain, because neutrinos don’t readily interact with ordinary particles, the beams can easily travel straight through the ground between the facilities - despite the curvature of the Earth. The beams from Fermilab are fired in two-second intervals, each sending billions of neutrinos directly toward the detectors. “This early result suggests that the NOvA collaboration will make important contributions to our knowledge of these particles in the not so distant future.” The 500-mile (800 km) subterranean path of the NOvA neutrino beam (Fermilab) “That the first neutrinos have been detected even before the NOvA far detector installation is complete is a real tribute to everyone involved,” said University of Minnesota physicist Marvin Marshak, Ash River Laboratory director. One of the first detections by NOvA of Fermilab-made neutrinos (Image courtesy of NOvA collaboration) 2013, while the Ash River facility was still under construction. And it’s already captured its first neutrinos - even before their setup is fully complete.Ĭreated by smashing protons against graphite targets in Fermilab’s facility just outside Chicago, Illinois, resulting neutrinos are collected and shot out in a beam 500 miles northwest to the NOvA far detector in Ash River, Minnesota, located along the Canadian border. (Scientists represent neutrinos with the Greek letter nu, or v.) It’s a very small-game hunt to catch neutrinos on the fly, and it uses some very big equipment to do the job. Department of Energy’s Fermilab, and they aren’t giving up on their latest neutrino safari: the NuMI Off-Axis Electron Neutrino Appearance experiment, or NOvA. Thankfully particle physicists are a tenacious lot, including the ones at the U.S. So it’s not surprising that weighing a neutrino isn’t as simple as politely asking one to step on a scale. Some of them have been around since the Big Bang and, just as you’ve read this, trillions of them have passed through your body (and more are on the way.) But despite their ubiquitousness neutrinos are notoriously difficult to study precisely because they ignore pretty much everything made out of anything else.
#Nova neutrino zip#
Incredibly lightweight - nigh massless, according to the Standard Model - as well as chargeless, they zip around the Universe at the speed of light and they don’t interact with any other particles. Neutrinos are some of the most abundant, curious, and elusive critters in particle physics.
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