IceCube detector uses entire Earth to measure interactions of neutrinos

Enlarge / The IceCube facility sits at the South Pole above an array of photodetectors, drawn into the image above. (credit: IceCube Collaboration, U. Wisconsin, NSF ) Neutrinos are one of the most plentiful particles out there, as trillions pass through you every second. But they’re incredibly hard to work with. They’re uncharged, so we can’t control their path or accelerate them. They’re also nearly massless and barely interact with other matter, so they’re hard to detect. All of this means that a lot of the predictions our physics theories make about neutrinos are hard to test. The IceCube detector , located at the South Pole, has now confirmed a part of the Standard Model of physics, which describes the properties of fundamental particles and their interactions. According to the Standard Model, neutrinos should become more likely to interact with other particles as their energy goes up. To test this, the IceCube team used neutrinos thousands of times more energetic than our best particle accelerators can make and used the entire planet as a target. Polar cube IceCube consists of hundreds of detectors buried in the ice under the South Pole. These detectors pick up particles that move through the ice. In some cases, IceCube sees a spray of particles and photons when something slams into one of the atoms in the ice. In other cases, particles simply nudge the atoms, liberating a few photons. There’s no neutrino source pointed at IceCube, though. Instead, it relies on natural sources of neutrinos. Some of these are produced far away in space, and travel great distances to Earth. Others are produced as cosmic rays slam into the atmosphere. Read 9 remaining paragraphs | Comments

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IceCube detector uses entire Earth to measure interactions of neutrinos

Study finds massive volcano range hidden in Antarctica’s ice

A new study claims to have found a huge expanse of volcanoes lurking beneath the ice in Antarctica . Scientists unearthed a total of 91 previously undiscovered volcanoes — some stretching up to 3, 850 metres (12, 600 feet) in height — in the region known as the West Antarctic Rift System (WARS). The area is comparable to the densely concentrated volcanic regions in east Africa and North America, according to researchers from the University of Edinburgh. Due to the ice sheets that cover its terrain, geologists have found it extremely difficult to study Antarctica for signs of volcanic systems. To overcome the obstacles posed by nature, the team of scientists remotely surveyed the underside of the ice using a digital elevation model known as Bedmap 2 DEM. They cross-referenced that info by examining aerial and satellite imagery. The results showed peaks of basalt rock poking up through the ice to form cone-shaped structures. Of those 178 edifices, 91 were outlined as previously undiscovered volcanoes. The study suggests that the density of the volcanoes in the WARS is one volcano per 4, 800 square miles, making it one of the world’s largest volcanic regions. Although, the results do not indicate whether the volcanoes are active, the data could allow future studies to determine just that. Whereas previous research has pointed to seismic activity in Antarctica, it is not thought to have impacted the present ice retreat. That wasn’t the case in Iceland, where studies found an increase in ice flow due to subglacial eruptions. Comparably, west Antarctica contains a thicker sheet of ice, but that may not be enough to prevent the affects of volcanic disturbance on future ice flow, suggest the scientists — especially during warmer periods . On the other hand, seeing as ice tends to slope downwards on a smooth surface, the cone-shaped structures could even act as deterrents against the current pace of glacial motion, claim the researchers. Source: University of Edinburgh, School of Geosciences (pdf)

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Study finds massive volcano range hidden in Antarctica’s ice