I’m a bit late onto this as I was rather busy last week, but I couldn’t resist passing on the news that the IceCube Neutrino Observatory has detected high-energy neutrinos (Tev) from the active galaxy NGC1068 (also known as Messier 77). The result is published in Science whence I stole this figure showing the concentration neutrinos correlated with the position of NGC1068, along with a couple of other sources.
The hotspot associated with NGC 1068 is the most intense feature observed on the whole sky. I won’t write any more because there are two videos about this discovery, the first a quick summary for general viewers:
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And the second is the full hour-long presentation as given last week.
Before I go for a lie down here is a video that goes with the discovery of the first astrophysical source of high-energy neutrinos!
You can find the two Science papers relating to the discovery here and here. The first abstract reads:
Previous detections of individual astrophysical sources of neutrinos are limited to the Sun and the supernova 1987A, whereas the origins of the diffuse flux of high-energy cosmic neutrinos remain unidentified. On 22 September 2017, we detected a high-energy neutrino, IceCube-170922A, with an energy of ~290 TeV. Its arrival direction was consistent with the location of a known γ-ray blazar, TXS 0506+056, observed to be in a flaring state. An extensive multi-wavelength campaign followed, ranging from radio frequencies to γ-rays. These observations characterize the variability and energetics of the blazar and include the detection of TXS 0506+056 in very-high-energy γ-rays. This observation of a neutrino in spatial coincidence with a γ-ray–emitting blazar during an active phase suggests that blazars may be a source of high-energy neutrino.
The other abstract is:
A high-energy neutrino event detected by IceCube on 22 September 2017 was coincident in direction and time with a gamma-ray flare from the blazar TXS 0506+056. Prompted by this association, we investigated 9.5 years of IceCube neutrino observations to search for excess emission at the position of the blazar. We found an excess of high-energy neutrino events, with respect to atmospheric backgrounds, at that position between September 2014 and March 2015. Allowing for time-variable flux, this constitutes 3.5σ evidence for neutrino emission from the direction of TXS 0506+056, independent of and prior to the 2017 flaring episode. This suggests that blazars are identifiable sources of the high-energy astrophysical neutrino flux.
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In the Dark 