In the summer of 1054, astronomers accidentally observed a nova in the sky, brighter than Venus. True, not for long, less than a month. Now in this place we see the crab-shaped nebula left behind by **. In 2020, the same Chinese at the Lhaaso Observatory used a detector array to detect 530 energies at 0 from 12 sources within the Milky Way1 to 14 quadrillion electron volts between photons. This discovery confirms the existence of Pevatron, which astronomers have been looking for for a long time. A year later, the data collected allowed people to identify them as Crab Nebulae.
The Pevatron (Ten Thousand Electron Volt Cosmic Ray Source) is a powerful cosmic ray accelerator. According to generally accepted models, these are supernova remnants: particles accelerated to the speed of light by the shock wave of a star. They are often referred to simply as "cosmic rays".
They are mostly made up of protons, but they can also have electrons and nuclei. They all carry an electric charge. As they move quickly through the Milky Way's magnetic field, their motion becomes confusing. This obscures where they were born. When these particles collide with interstellar gas near supernova remnants, they emit gamma rays (the highest energy of light).
Previously, physicists had only observed high-energy photons, which were supposed to be created during the acceleration of the interaction of protons and other charged particles with the cosmic environment. The magnetic field does not deflect these gamma rays. But the Lhaaso staff found that in our galaxy there are still more than 001 PEV Extreme More Powerful Accelerator. Now, with the help of gamma-ray astronomy, the ancient mystery of the origin of cosmic rays has been solved.
Lhaaso saw powerful gamma rays born near supernova remains, but at the same time did not confirm the generally accepted model for understanding the origin of Pevatron. According to Yuri Stenkin, co-author of the new data science publication, in this case, the ** of cosmic rays is not a supernova shell, but a pulsar in a crab nebula. It has a diameter of about 25 kilometers and a rotation speed of 30 revolutions.
An article in the journal Nature provides the coordinates of 12 more such sources - candidate sources for Pevatron. Stankin said they also have pulsars nearby, but only 4 out of 12 have supernova remnants.
All of this forces us to rethink the existing Pevatron models, which have stayed within the framework of assumptions. Because there is no better explanation for the mechanism of the emergence of pevatrons. Stenkin also highlighted the Boris Trubnikov model, which was proposed in 1990. Among them, cosmic rays are accelerated when plasma jets escaping from the cores of celestial bodies such as quasars, radio galaxies, and active galaxies burst.
Trubnikov succeeded in very accurately ** the observed spectral indicators. In models with supernova shells, this indicator is simply adjusted due to lack of information. Pulsars also emit similar "jets", so Trubnikov's model has the opportunity to evolve based on the work done by Lhaaso.
To further study this direction, it is planned to modernize ground-based telescopes and launch high-energy space gamma observatories. More importantly, however, there is hope for the development of neutrino astronomy. Gamma-ray observatories are unable to detect signals from crosshairs from other galaxies because high-energy gamma rays are quickly scattered by cosmic microwave background radiation.
Neutrinos reach us from such a great distance. The development of the technical capabilities of the neutrino telescope will make it possible to study extragalactic hadrons. This will most likely not lead scientists to find answers, but to ask more questions. In any case, something new and interesting awaits them in the spectrum of observed cosmic rays.