A new discovery about the source of the vast energy in cosmic rays
Ultra-high-energy cosmic rays that occur in extreme astrophysical environments—such as the tumbling environments near black holes and neutron stars—have more energy than the high-energy particles found in the sun. In fact, the particles that make up these energy flows have about 10 million times the energy of particles accelerated in the most extreme particle environment on Earth, the man-made Large Hadron Collider.
Where does all this energy come from? For years, scientists thought it came from shocks that occurred in extreme astrophysical environments—for example, when a star exploded before forming a black hole, causing a huge explosion and stirring up particles.
The theory makes sense, but according to new research published this week Astrophysical Journal Communicationsthe observations can be better explained through different mechanisms. The researchers found that the source of cosmic ray energy is more likely to be magnetic turbulence. The authors of the paper found that the magnetic fields in these environments entangle and rotate, causing particles to rapidly accelerate and dramatically increase their energy until they suddenly stop.
“These findings help answer a persistent question of great interest to both astrophysicists and particle physicists alike: how these cosmic rays obtain their energy,” said Luca, an associate research scientist at the Columbia Astrophysical Laboratory and one of the paper’s authors. Luca Comisso said.
The paper complements research published last year by Comiso and collaborators on energetic particles from the sun, which they also found were produced from the magnetic field in the sun’s corona. In that paper, Comiso and his colleagues discovered ways to better predict where these high-energy particles will appear.
Ultra-high-energy cosmic rays are several orders of magnitude more powerful than the sun’s high-energy particles: up to 1020 electron volts, while particles from the sun can reach 1010 Electron volts, a difference of ten orders of magnitude. (To understand the huge difference in scale, consider the weight difference between a grain of rice, which has a mass of about 0.05 grams, and a 500-ton Airbus A380, the world’s largest passenger aircraft.) “Interesting “But the two planes’ extremely different environments have something in common: Their magnetic fields are highly entangled, and the nature of this entanglement is crucial for exciting particles,” Comiso said.
“It is worth noting that the data from ultra-high-energy cosmic rays clearly favor predictions of magnetic turbulence rather than predictions of impact acceleration. This is a real breakthrough in the field,” said Glenn, a professor of physics and author of the paper. Glennys R. Farrar said.
The research was supported by the National Science Foundation.
2024-12-10 19:20:40