A mysterious cosmic ray hits the Earth – DW – 11/24/2023

Japanese researchers were able to capture the second most energetic cosmic ray ever observed, which they named “Amaterasu” in honor of the Japanese sun god, as the team explained in its article. Scientific article published in Sciences.

The lightning strike was captured on Earth on May 27, 2021 within the framework of the Array Telescope project by an international team led by Associate Professor Toshihiro Fujii from the Faculty of Science and the Yuichiro Nambu Institute for Theoretical and Experimental Physics. From Osaka Metropolitan University.

Cosmic rays

Cosmic rays are energetic charged particles originating from galactic and extragalactic sources, and can reach energies exceeding 1018 electron volts or exaelectronvolts (EeV), about a million times the power of the most powerful man-made particle accelerators. .

Extremely high-energy storms, such as Amaterasu, with 244 MeV, or 2.4 trillion times the lightning energy of a typical Earth storm, are extremely rare.

Professor Fujii said: “When I first discovered this high-energy cosmic ray, I thought there must be a mistake, because it showed an energy level unprecedented in the past three decades.” It’s a statement Released today, coinciding with the publication of the article in Sciences.

Cosmic ray “oh my god”

So far, only one more powerful cosmic ray has been observed, in 1991, a ray called Oh My God, with an energy of 320 MeV.

The team was unable to determine the origin of Amatrasu, but they hope that its discovery and study will pave the way to clarify its origin and the origin of cosmic rays themselves.

He added: “No promising astronomical object has been identified that matches the direction from which the cosmic ray arrived, indicating the possibilities of the existence of unknown astronomical phenomena and new physical origins beyond the Standard Model.”

Fujii noted that the team remains committed to the Array Telescope and that they look forward to improving its capabilities in the future.

The Array telescope is an experimental cosmic ray detector launched in 2008 and consists of 507 surface scintillation stations covering an area of ​​700 square kilometers in the US state of Utah.

little (if, Sciences(Osaka Metropolitan University)