Powerful Cosmic Rays Believed To Be From Nearby Pulsar Discovered

Scientists have discovered high-energy cosmic rays after over a decade of painstaking data collection that can unlock new avenues about our understanding of the universe regarding cosmic processes that emit colossal amounts of energy. Researchers at the H.E.S.S (High Energy Stereoscopic System) observatory, located in Namibia, discovered the cosmic electrons and positrons that have energies over 10 tera-electronvolts (1 TeV corresponds to 10*12 electronvolts), which is about 1000-billion times greater than that of visible light, the findings published in journal Physical Review Letters showed.

"We've uncovered data in a crucial and previously unexplored energy range. It's likely to remain a benchmark for the coming years," said Werner Hofmann from the Max Planck Institute for Nuclear Physics in Heidelberg.

Since these charged particles are deflected in all directions by the magnetic field in the cosmic background, scientists say it is difficult to determine their origin. However, they speculate that a pulsar (stellar remnants with a strong magnetic field), which can be at most a few thousand light years away, could be the source. Notably, such particles come from all sorts of wild cosmic events like exploding stars (supernovae), distant galaxies, and even our own sun during solar flares.

How was the discovery made?

The scientists analysed a huge data set collected over a decade by four of the H.E.S.S telescopes. They used a new algorithm based on a pixel-by-pixel comparison, using sophisticated statistical modelling to identify cosmic electrons with unprecedentedly low background contamination.

This resulted in a statistically high-quality data set for the analysis of cosmic electrons. In particular, the researchers succeeded in measuring electrons and positrons with energies of up to 40 TeV.

Also Read | World's Highest Gamma Ray Telescope Set To Peek Into Universe's Secrets From Ladakh

What is H.E.S.S?

The High Energy Stereoscopic System is a ground-based gamma-ray telescope in the highlands of Namibia and sensitive in the energy range from 50 GeV to 100 TeV. It consists of four 12-metre diameter reflecting telescopes surrounding a central telescope.

The observatory captures and records the faint Cherenkov radiation produced by the heavily charged particles and photons that enter the Earth's atmosphere, producing a shower of particles in their wake. During its more than 15 years of observation, H.E.S.S has helped with the discovery of over 100 sources in comparison to the around 12 sources known before its observations began.