A team of researchers from the Ruhr-Universität Bochum (RUB) has produced interesting new software to discover the unknown causes of cosmic rays. The cause of high-energy radiation reaching Earth from space has been unknown for a century.
The team has developed a computer program that simulates the transport of cosmic rays through space. This new invention is able to determine which celestial objects cause the rays to reach the Earth’s surface, instead of relying on theoretical models.
The discovery of cosmic rays
Cosmic rays are a form of high-energy radiation that originate in unknown territory outside of Earth’s solar system. They were discovered by scientists 100 years ago and since then researchers have been trying to figure out where they came from.
Researchers have faced a number of problems trying to pinpoint the source of the rays. When viewed from Earth during the day, cosmic rays simply look identical to the sky. This happens because the Sun’s light is scattered by the Earth’s atmosphere and spreads evenly across the sky.
As they interact with cosmic magnetic fields on their way to Earth, cosmic radiation breaks up before it has a chance to hit Earth. This means that all we can see in the sky is a uniformly illuminated image, leaving the cause of the high-energy radiation unknown.
The CRPropa program
The simulation program was developed as a result of the international collaboration of 17 researchers from Germany, Spain, the Netherlands, Italy, Croatia, England and Austria.
Julien Dörner, PhD student at RUB, said: “Our program, known as CRPropa, allows us to trace the trajectories of particles from their formation to their arrival at Earth, and this for all energies that we can observe from Earth”.
“We can also fully explain the interaction of particles with the matter and photon fields of the Universe.”
The program not only simulates the propagation of cosmic rays, but also collects neutrinos and gamma rays produced as a result of cosmic ray interactions.
Dr. Patrick Reichherzer, a postdoctoral researcher at the RUB, explained: “Unlike cosmic rays, these messenger particles can be observed directly from their sources, as they arrive at Earth on a straight path.”
“We can also use the software to predict these neutrino and gamma-ray signatures from distant galaxies, such as starbursts or active galaxies.”
This new simulation program is currently the most advanced cosmic ray software and allows researchers to uncover new data about the Universe.
“We can explore new energy ranges in the simulation that could not be fully captured in such detail with the programs available so far,” said Professor Karl-Heinz Kampert from the University of Wuppertal.
“Most importantly, we can develop a theoretical model that describes the transition of cosmic rays from our own galaxy to a fraction coming from distant galaxies and compare it to observations.”
The program is an important step in understanding how cosmic rays transport and interact through the Universe. CRPropa will contribute significantly to the undiscovered origin of cosmic rays.