A team of scientists from the Chinese Academy of Sciences (CAS) has made a groundbreaking discovery in space.
They have detected the highest-energy gamma-ray line ever observed, reaching up to 37 million electron-volts.
This finding came from an extremely bright gamma-ray burst (GRB), an intense explosion in space, and marks the most energetic light emitted by any celestial object in the universe.
Gamma-ray bursts are the most powerful explosions in the cosmos.
They can occur when a massive star collapses or when two compact objects like neutron stars or black holes collide.
The particular GRB that led to this discovery, known as GRB 221009A, is nicknamed the “brightest of all time.”
It was detected on October 9, 2022, and was so powerful that telescopes around the world observed it.
The research team, which included experts from the Institute of High Energy Physics (IHEP), Yunnan Observatories, Hebei Normal University, and Guizhou Normal University, analyzed data from two special space gamma-ray monitors: GECAM-C and Fermi/GBM.
GECAM-C provided accurate measurements of the lower energy spectrum of this GRB, while Fermi/GBM covered the higher energy levels where the gamma-ray line appeared.
The burst was so intense that the Fermi/GBM detector experienced data loss during its brightest moments, making the analysis difficult. However, the GECAM-C instrument, designed to handle such bright bursts, did not encounter this issue.
The GECAM-C data was then used to correct and enhance the data from Fermi/GBM, allowing the team to derive accurate and reliable information.
After carefully analyzing the data and overcoming various challenges, the researchers discovered a series of gamma-ray lines during the burst, including one with an energy level of 37 million electron-volts.
They also found that the energy of these gamma-ray lines changes over time in a predictable way, following a power-law pattern. This consistency provided solid evidence that these gamma-ray lines were indeed produced by the GRB.
This discovery is a significant step forward in understanding gamma-ray bursts and the physics behind their powerful explosions.
It sheds new light on the nature of these cosmic events and their relativistic jets, helping scientists better understand the most energetic phenomena in the universe.
