IceCube / NSF
Since the French physicist Pierre Auger has proposed in 1939 which Cosmic rays They have to carry large amounts of energy, and scientists have been puzzled as to what the powerful clusters of protons and neutrons that rain down on Earth’s atmosphere could produce. One possible way to identify such sources is to cancel the paths of high-energy cosmic neutrinos to Earth, as they emerge from cosmic rays that collide with matter or radiation, producing particles which then decay into neutrinos and gamma rays.
Scientist with it’s batu The Antarctic Neutrino Observatory has now analyzed the decade-long discovery of neutrinos and has found evidence that an active galaxy called Messier 77 (also known as the Squid Galaxy) is a strong candidate for a high-energy neutrino emitter, according to a new card Published in the journal Science. This takes astrophysicists one step further in solving the mystery of the origin of high-energy cosmic rays.
“These observations are the beginning of the ability to actually do neutrino astronomy,” Janet Conrad, MIT IceCube member APS physics. “We have struggled for a long time to see a potential source of such highly sought-after cosmic neutrinos and now we have seen one. We broke the barrier ”.
Like this Tell us in advanceAnd neutrino Travel close to the speed of light. John Updike’s 1959 poem, “Cosmic Gala“Praises the two most distinctive features of neutrinos: they have no charge, and for decades physicists have thought they have no mass (in fact, they have very little mass). Neutrinos are the most abundant subatomic particles in the universe, but they rarely interact with any type of material. We are constantly bombarded every second with millions of these tiny particles, yet they pass us by without us noticing. That’s why Isaac Asimov called it the “ghost particle”.
Nicole R. More details, IceCube / NSF
This low reaction rate makes the neutrino Very difficult to detect, but because it is so light, it can escape unhindered (and therefore largely unchanged) by colliding with other particles of matter. This means they could provide astronomers with valuable clues to distant systems, supported by what can be studied with telescopes across the electromagnetic spectrum, as well as gravitational waves. Together, these various sources of information are called “Multiple Messenger” astronomy.
Most neutrino hunters bury their experiments deep in the earth and it is best to eliminate strong interference from other sources. In the case of the IceCube, this collaboration involves a series of optical sensors the size of a basketball buried deep in the Antarctic ice. On the rare occasions when transient neutrinos interact with atomic nuclei in ice, collisions produce charged particles that emit ultraviolet light and blue photons. This is captured by the sensor.
So IceCube is well positioned to help scientists advance their knowledge of the origin of high-energy cosmic rays. Like Natalie Wolcoffer convincingly Explained in Quanta In 2021:
Cosmic rays are just the nucleus of an atom: a proton or a group of protons and neutrons. However, the rare cosmic rays known as “ultra-energetic cosmic rays” have the same energy as a professionally presented tennis ball. They are millions of times more energetic than the protons orbiting the circular tunnel of the Large Hadron Collider in Europe at 99.9999991% the speed of light. In fact, the most energetic cosmic ray ever discovered, dubbed the “oh my God” particle, hit the sky in 1991 at 99.9999999999999999999951 percent of the speed of light, energizing a bowling ball that fell from shoulder to foot. .
But where do such powerful cosmic rays come from? One of the strong possibilities Galaxy core active (AGNs), which is found at the center of several galaxies. The energy comes from the supermassive black hole at the center of the galaxy and / or from the rotation of the black hole.
