Reacción a "Nobel Prize in Physics Awarded to Francis Halzen for the discovery of high-energy neutrinos of astrophysical origin and for his “decisive contributions” to the IceCube Observatory"

Neutrinos are particles that interact with matter very rarely, so we need enormous detectors to study them. But that very property also makes them ideal messengers for studying the universe and, in particular, for identifying the astrophysical sources that produce them. Since they are neutral particles and interact very little during their journey, neutrinos reach us without being deflected, and when we detect them, their direction allows us to pinpoint the location in the universe where they were produced. The information they provide is, therefore, complementary to that of other, more common cosmic messengers, such as photons or charged particles like protons. Francis Halzen’s brilliant idea was to use the deep ice at the South Pole as a detection medium and to equip approximately one cubic kilometer of that ice to observe very high-energy neutrinos. Shortly after becoming operational, IceCube succeeded in detecting, for the first time, a population of very high-energy cosmic neutrinos—some with energies vastly greater than those we can achieve in our accelerators—thus opening a new window for studying the most extreme natural accelerators in the universe.