The IceCube Neutrino Observatory, operated by the University of Wisconsin-Madison (UW-M), located at the Amundsen–Scott South Pole Station in Antarctica, is one of the most ambitious neutrino observatories in the world. Behind this observatory is the IceCube Collaboration, an international group of 300 physicists from 59 institutions in 14 countries. Relying on a cubic kilometer of ice to shield from external interference, this observatory is dedicated to the search for neutrinos. These nearly massless subatomic particles are among the most abundant in the Universe and constantly pass through normal matter.
The IceCube Neutrino Detector is an observatory unlike any other. Using sensors embedded inside a square kilometer chuck of Antarctic ice, it detects tiny particles called neutrinos, which rarely interact with ordinary matter and are incredibly hard to capture. IceCube has had several major successes in the last few years, including this summer’s announcement of a neutrino map of the Milky Way galaxy. But scientists are pushing up against the limits of IceCube’s capabilities, and plans are in the works for IceCube-Gen2: a detector 5 times as sensitive and 8 times as large, with a radio antenna array across four hundred square kilometers. IceCube Gen2 will increase the number of neutrino detections by an order of magnitude, and will be able to better pinpoint the sources from which the neutrinos are emitted.
Dark matter is one of the thorniest mysteries of modern cosmology. On the one hand, astronomers have gathered a wealth of supporting evidence through galaxy clustering statistics, gravitational lensing, and cosmic microwave background fluctuations, on the other hand, there are no particles in the standard model of particle physics that could account for dark matter, and we haven’t been able to detect its effect locally. It’s a solid theory where we just can’t seem to fully pin it down. That usually means we’re just a breakthrough away from confirming or overthrowing dark matter. The good news is that there are several projects searching for dark matter, and one of them, the IceCube Neutrino Observatory, has just released a new result.
Researchers using the IceCube Neutrino Observatory have detected neutrinos emanating from the energetic core of an active galaxy millions of light-years away. Neutrinos are difficult to detect, and finding them originating from the galaxy is a significant development. What does the discovery mean?
Is there anywhere in the Universe where we can escape from radiation? Certainly not here on Earth. And not in space itself, which is filled with diffuse radiation in the form of gamma rays and neutrinos. Scientists have struggled to explain where all those gamma rays and neutrinos come from. A trio of researchers is proposing a source for all that radiation in a new paper: resting black holes.
Dark matter remains one of the greatest mysteries in science. Despite decades of astronomical evidence for its existence, no one has yet been able to find any sign of it closer to home. There have been dozens of efforts to do so, and one of the most prominent just hit a milestone – the release and analysis of 8 years of data. The IceCube Neutrino Observatory will soon be releasing results from those 8 years, but for now let’s dive in to what exactly they are looking for.
Neutrinos are notoriously finicky particles. Hundreds of trillions pass through a person’s body every second, yet they hardly seem to interact with anything (though they actually do a lot). Even more hard to find are the “high energy” neutrinos that are believed to be formed as the outcome of some of the most violent events in the universe. Now, researchers using NASA’s Swift telescope have found a high energy neutrino for the first time from one type of those ultra-violent events – a tidal disruption. But something was a little bit off about it.
We don’t know what dark matter is. We do know what it isn’t, and that’s a problem. Matter is made of elementary particles, from the quarks and electrons that make up atoms and molecules, to primordial neutrinos spread throughout the cosmos. But none of the known elementary particles can comprise dark matter, so what is it?
The neutrino is a confounding little particle that is believed to have played a major role in the evolution of our Universe. They also possess very little mass, have no charge, and interact with other particles only through the weak nuclear force and gravity. As such, finding evidence of their interactions is extremely difficult and requires advanced facilities that are shielded to prevent interference.
When giant stars die in impressive supernova blasts, about 99% of the energy released goes into producing a flood of neutrinos. These tiny, ghostly particles slip through tons of matter like it’s not even there. But a new generation of detectors will be able to catch them, telling us of the inner machinations of the deaths of stars.