H.E.S.S. (High Energy Stereoscopic System) scientists publically revealed their latest galactic discovery in the international science journal, Nature, on 16 March 2016. These scientists were able to pinpoint the most powerful source of cosmic radiation – which, up to now, remained a mystery.

Part of this team of scientists are Prof Pieter Meintjes and Dr Brian van Soelen, both in the University of the Free State (UFS) Department of Physics. Dr Van Soelen explains that they have discovered a proton PeVatron – a source that can accelerate protons up to energies of ~1 PeV (10^15 eV) – at the centre of the Milky Way. The supermassive black hole called Sagittarius A has been identified as the most plausible source of this unprecedented acceleration of protons.

The protons are accelerated to Very High Energy (VHE) gamma rays. The energy of these protons are 100 times larger than those achieved by the Large Hadron Collider at CERN (the European Organization for Nuclear Research).

According to Dr Van Soelen, the fact that this research has been published in Nature demonstrates the importance and pioneering nature of the research conducted by H.E.S.S. The H.E.S.S. observatory – operational in Namibia – is a collaboration between 42 scientific institutions in 12 countries.

In 2006, H.E.S.S. was awarded the Descartes Prize of the European Commission – the highest recognition for collaborative research – and in 2010 the prestigious Rossi Prize of the American Astronomical Society. The extent of the observatory’s significance places it among the ranks of the Hubble Space Telescope and the telescopes of the European Southern Observatory in Chile.

“The next generation VHE gamma-ray telescope,” Dr Van Soelen says, “will be the Cherenkov Telescope Array (CTA), which is currently in the design and development stage.” Both Dr Van Soelen and Prof Meintjes are part of this project as well.

H.E.S.S. has issued a complete statement about the paper published in Nature.