Are extragalactic sources of ultra-high-energy cosmic rays efficient emitters of neutrinos?

The search for the sources of ultra-high-energy cosmic rays (UHECRs) is not a simple one. UHECRs, which are a mixture of protons and heavy nuclei, are the highest energy particles ever measured. They should produce “hotspots” of high-energy neutrinos if they interact with other particles near their point of origin. Six years ago, a first […]

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Improved reconstruction of low-energy events in IceCube

Every six minutes, a neutrino flies through the Antarctic ice sheet, and close to an IceCube sensor—also called a DOM—it interacts with a molecule of ice and creates a tiny amount of light that triggers data-taking for an event in the IceCube neutrino detector. If this is a high-energy event, a beautiful track or a […]

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IceCube unveils the world’s most precise search for mysterious new neutrino interactions

Neutrinos have mass. Their mass is small, extremely small in fact, but contrary to what the Standard Model of particle physics predicts, they do have mass.  A consequence of this nonstandard property is that neutrinos oscillate, which means that as they speed through matter or space, their flavor—or type—changes at a rate that depends on […]

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Improvements to deciphering the cosmic muon neutrino flux

Neutrino astronomy had a pivotal moment in 2013 when the IceCube Collaboration announced that their South Pole neutrino telescope had detected the first evidence of an astrophysical neutrino flux. This was confirmed in 2015 with an independent search in the Northern Hemisphere, also by IceCube. Since then, IceCube and other experiments have learned more about […]

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IceCube explores active galactic nuclei as sources of the astrophysical neutrino flux

In 2013, the IceCube Neutrino Observatory detected very high energy particles called neutrinos that arrived at Earth from outer space. Not only did IceCube confirm the existence of astrophysical neutrinos, but they also proved that these elusive particles could be detected by their cubic-kilometer-sized telescope buried in the South Pole ice. Even though IceCube had […]

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Brightest infrared objects are likely not responsible for the astrophysical neutrino flux

By Madeleine O’Keefe and Pablo Correa In the constellation Ursa Major, there is a galaxy with the uncanny appearance of a particular dental hygiene tool. Aptly nicknamed the “Toothbrush” galaxy, Mrk 273 is actually a merger of two galaxies and an example of an ultraluminous infrared galaxy (ULIRG). It might be a source of astrophysical […]

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