Scientists in the US computer simulation of gamma rays solved a long-standing mystery - and their findings confirmed, in fact, a theory first put forward by Israeli scientists
A mystery that has occupied scientists for 30 years has been solved these days in a study by Columbia University and Barnard College in the USA. He confirmed a theory put forward for the first time by two Israeli scientists: Prof. Eli Waxman from the Weizmann Institute and Prof. Avi Leib, currently at the Institute of Astrophysics at Harvard University in Boston.
The study found that most of the gamma rays that reach our galaxy are created in galaxy clusters and various massive space bodies. The discovery provides a new angle of view for the way in which the structures of stars and galaxies in the universe are formed, and for the origin of the magnetic fields in the intergalactic medium.
The new study is reported by Dr. Caleb Sharaf from "Columbia" and Rashmi Mukherjee from "Barnard College" in the journal "Astrophysical Journal". They based their work on analyzing data accumulated over nine years regarding the distribution of gamma rays that reached the Earth from the depths of the universe. The special research satellite for this topic, "Compton", has focused on this since it was launched by NASA in the early 90s. Its database already contains information about 2469 galaxy clusters (!).
The researchers, who used sophisticated statistical analysis methods, claim that the sky surrounding most large galaxy clusters is significantly brighter in gamma radiation than the other regions of the universe. They explained that their research solves a riddle not only about the origin of gamma radiation - also about the structures that form in the universe under the influence of gravity.
Gamma rays are the most high-energy form of electromagnetic radiation. In our own galaxy, the Milky Way, gamma rays are created as cosmic rays and atomic particles move
At speeds close to the speed of light collide in the interstellar gas or when particles and antiparticles meet. Black holes and neutron stars are suitable environments for the generation of gamma radiation.
The galaxy clusters are the largest bodies that formed in the universe, under the influence of gravity. In the study, clusters containing thousands of galaxies each, in the dimensions of the Milky Way, were examined. They continue to absorb materials such as gases and even other entire galaxies from the space surrounding them.
The mass of a cluster of galaxies - which is mainly dark matter, is the source of gravity exerted on its environment. Matter is attracted to the cluster at a speed of up to several thousand kilometers per second. in this flux,
The acceleration of the electrons that receive an additional boost from magnetic fields is increased - up to close to the speed of light. So they collide with photons, particles or in the field of millimeter radiation - the caution of light, which was created after the big bang. The light particles, the photons, are raised due to the collision to the energy level of gamma radiation photons. The gamma rays form a halo around the galaxy clusters.
In the past, other scientists believed that gamma rays are created in a different way: from quasar-like galaxies - called blazars - which "feed", by absorbing matter, sometimes stars that were pulled into a huge, supermassive black hole.
The new study also confirmed a theory about what is known as the "Cosmic Network". It is similar to the webs that the spider weaves. According to this theory, the matter in the universe is arranged so that it forms a cosmic network. The luminous galaxies form along filaments of normal and dark matter, like pearls strung on a string. The clusters are formed by the intersections of the cosmic threads. The electrons that fuel the process of creating the gamma rays, "run" into the clusters and along the channels of the material threads connecting the galaxies and the clusters.
Alex Doron
