When cosmic rays strike Earth’s atmosphere, they produce air showers containing atmospheric muons and neutrinos—tiny, nearly massless particles—that rain down on Earth. The atmospheric neutrinos are then detected by the IceCube Neutrino Observatory at the South Pole. These atmospheric neutrinos come in three different flavors—electron, muon, and tau–and can become a different flavor or “oscillate” […]
Since 2016, the IceCube Neutrino Observatory—a detector buried in a cubic kilometer of Antarctic ice—has been issuing real-time alerts sent to the public within minutes of the detection of astrophysical, ghostlike particles called neutrinos. IceCube’s prompt observations are key in the emerging field of multimessenger astronomy where the combined measurements across the electromagnetic spectrum are […]
Despite making up roughly 85% of all matter in the universe, dark matter (DM) still remains an enigma to astronomers and physicists. One outstanding question is the microscopic nature of DM, and thus far, no experiment has been able to determine what it is made of. To probe the nature of DM, scientists look for […]
Gravitational waves (GWs) are produced by some of the most extreme astrophysical phenomena, such as black hole and neutron star mergers. They have long been suspected as astrophysical sources of neutrinos, ghostlike cosmic messengers hurtling through space unimpeded. Thus far, common astrophysical sources of neutrinos and photons, as well as common sources of gravitational waves […]
When a star reaches the end of its thermonuclear evolution, it explodes, giving rise to neutron stars and black holes. Called core-collapse supernovae (CCSNe), these explosions are triggered by the implosion of the dying star’s core. The ejecta from the CCSN can then interact with the dense circumstellar medium where charged particles can be accelerated. […]
On October 9th, 2022, an unusually bright pulse of high-energy radiation whizzed past Earth, captivating astronomers around the world. The luminous emission came from a gamma-ray burst (GRB), one of the most powerful classes of explosions in the universe. Named GRB 221009A, it triggered detectors at NASA’s Gamma-ray Burst Monitor and Large Area Telescope (both on […]
Atmospheric muons and neutrinos are the most abundant signals detected in IceCube. They are produced in cosmic-ray-induced air showers in the Earth’s atmosphere. Cosmic rays are high-energy protons and heavier nuclei traveling through space. When these cosmic rays reach Earth and collide with atoms in the atmosphere, they create an avalanche-like cascade of secondary particles […]
White dwarfs are very dense, compact objects that are one of the possibilities for the final evolutionary state of stars. If they happen to be in a binary system with another companion star, the white dwarf may pull material from the companion star onto its surface. In this case, if enough material is accumulated, a […]
The IceCube Neutrino Observatory, a cubic-kilometer-sized neutrino telescope, searches for high-energy neutrinos of astrophysical origin. Located at the geographic South Pole, IceCube consists of 5,160 digital optical modules (DOMs) across 86 vertical cables (strings) embedded deep within the Antarctic ice, as well as a surface array, IceTop, and a denser inner subdetector, DeepCore. When neutrinos […]
The IceCube Collaboration has reported two candidate events for the final unobserved Standard Model cosmic messenger: astrophysical tau neutrinos. And one of these neutrino events, as with previous prominent particles detected by the IceCube Neutrino Observatory, has been given its own nickname. Double Double, an event with a high probability of being produced by a […]