Gamma-ray burst is the most violent explosion in the universe. The research on gamma-ray burst, including central engine, magnetized dynamics of plasmas, and the radiation, is one of the hot topics in the high-energy astrophysical research.

The so-called "brightest of all time" gamma-ray burst, GRB 221009A, has been detected by satellites and ground-based telescopes in the world. The burst has the strong emission in the TeV energy band.

Researchers led by Profs. MAO Jirong and WANG Jiancheng from the Yunnan Observatories (YNAO) of the Chinese Academy of Sciences (CAS) have explored the radiation mechanism of GRB 221009A.

Their findings were published in The Astrophysical Journal on April 4.

The researchers proposed a novel radiation mechanism, i.e., the radiation of the relativistic electrons in the random and small-scale magnetic field. They applied this mechanism to explain the very high energy emission of GRB 221009A. In particular, in this mechanism, they utilized the Landau damping, a plasma effect, to constrain the emission of GRB 221009A in the TeV energy band.

Furthermore, they treated the mechanism as a kind of coherent radiation to reproduce the emission flux of GRB 221009A. Thus, the observation properties of the burst are theoretically interpreted by this novel mechanism.

The study is important for further understanding on the radiation mechanism of high-energy objects in the future. It is supported by the National Natural Science Foundation of China and Yunnan Revitalization Talent Support Program.

YNAO is a partner inside the LHAASO collaboration. The research reported here is a theoretical exploration focusing on the observational results obtained from the Chinese large scientific device.