The project’s first major discovery was the detection of neutrinos from astrophysical sources outside our solar system. One of the most notable sources was TXS 0506+056, located in collaboration with other observatories that collected various gamma-ray, optical, and radio signals. TXS 0506+056 is a high-energy blazar, a galaxy that appears extremely bright and revolves around a supermassive black hole. The researchers looked for other objects with similar characteristics and confirmed that this class of sources is capable of producing high-energy neutrinos. More recently, they have been able to observe the Milky Way as a diffuse source of neutrinos.
In addition to astronomy, IceCube has made significant contributions to our understanding of the nature and behavior of these particles. For example, there are three known types of neutrinos, and last year’s Nobel laureates in physics discovered that these particles can transform from one type to another as they travel. IceCube has enabled increasingly precise measurements of this phenomenon.
“Another area of research is cosmic rays, which is what I focus on,” says Díaz Vélez. “We have discovered that they do not come uniformly from all directions but rather from preferred directions, and this tells us about the distribution of their sources in the galaxy.”
Cosmic rays consist of protons and nuclei of heavier atoms, and they constitute a very high portion of the project’s data. “Detecting a neutrino is like looking for a needle in a haystack,” the researcher says. “For every neutrino IceCube detects, more than a million muons produced by cosmic rays are detected.”
Díaz Vélez serves as the product coordinator for the IceCube collaboration, overseeing the processing of experimental data and the production of simulations. “This involves calculating the direction of arrival, the energy, and the type of particle detected every two milliseconds,” he says. “We also need to simulate cosmic rays and neutrinos at comparable rates. Both tasks require high-performance computing networks distributed around the world, totaling approximately 10,000 CPU cores and 1,000 GPUs.”