November 2, 2024

A Super Cosmic Ray Accelerator – Chinese Astronomers Discover Giant Ultra-High-Energy Gamma-Ray Bubble

LHAASO has actually recognized a very cosmic ray accelerator in a gamma-ray bubble in the Cygnus area, marking a substantial development in comprehending cosmic rays with energies surpassing 10 PeV and their origins within the Milky Way. Measurements of cosmic rays in past years have actually exposed a break around 1 PeV in the energy spectrum (i.e., the circulation of cosmic ray abundance as a function of the particle energy), which is called the “knee” of the cosmic ray energy spectrum due to its shape looking like a knee joint.Rendering of ultra-high-energy cosmic rays proliferation in interstellar area. The origin of cosmic rays in the “knee” region is still an unsolved secret and one of the most intriguing topics in cosmic ray research in current years.Discovery of a Super Cosmic Ray AcceleratorLHAASO has found a huge ultra-high-energy gamma-ray bubble structure in the Cygnus star-forming region, with multiple photons surpassing 1 PeV inside the structure, with the highest energy reaching 2.5 PeV, suggesting the existence of an extremely cosmic ray accelerator inside the bubble, which constantly speeds up high-energy cosmic ray particles with energies of up to 20 PeV and injects them into interstellar area. With increasing observation time, LHAASO is expected to spot more super cosmic ray accelerators, and hopefully resolve the secret of the origin of cosmic rays in the Milky Way.LHAASOs observation has also indicated that the super cosmic ray accelerator inside the bubble considerably increases the cosmic ray density in the surrounding interstellar area, far exceeding the typical level of cosmic rays in the Milky Way.

Measurements of cosmic rays in previous decades have exposed a break around 1 PeV in the energy spectrum (i.e., the distribution of cosmic ray abundance as a function of the particle energy), which is called the “knee” of the cosmic ray energy spectrum due to its shape looking like a knee joint.Rendering of ultra-high-energy cosmic rays propagation in interstellar area. The origin of cosmic rays in the “knee” area is still an unsolved mystery and one of the most appealing topics in cosmic ray research study in current years.Discovery of a Super Cosmic Ray AcceleratorLHAASO has found a giant ultra-high-energy gamma-ray bubble structure in the Cygnus star-forming region, with numerous photons surpassing 1 PeV inside the structure, with the greatest energy reaching 2.5 PeV, showing the presence of a super cosmic ray accelerator inside the bubble, which continuously accelerates high-energy cosmic ray particles with energies of up to 20 PeV and injects them into interstellar space. With increasing observation time, LHAASO is expected to spot more incredibly cosmic ray accelerators, and ideally solve the mystery of the origin of cosmic rays in the Milky Way.LHAASOs observation has likewise shown that the very cosmic ray accelerator inside the bubble significantly increases the cosmic ray density in the surrounding interstellar area, far going beyond the typical level of cosmic rays in the Milky Way.