Deep insights from the very-high-energy afterglow of a gamma-ray burst

TeV emission over three nights with totally unexpected hard spectral shape—the latest result from H.E.S.S. on the cosmic explosions known as gamma-ray bursts. Unique insights were possible due to the unusual closeness of GRB 190829A—only 1 billion light years away! Published in Science; see also our press release.

H.E.S.S. observations of a Nova outburst

The first TeV detected Nova provides insights in to cosmic particle acceleration. RS Ophiuchi is a binary star system where a white dwarf star accretes material from its red giant companion. Roughly every 15 years, enough material has built up on the white dwarf surface to trigger a thermonuclear explosion. The Nova of August 2021 produced an expanding shock wave at which particles were accelerated to Teraelectronvolt energies. Using H.E.S.S. we could watch particles being accelerated in real time and test acceleration theory. These findings were published in Science; see also our press release.

Relativistic Jet Dynamics from gamma-ray observations of a Microquasar

The microquasar SS 433 stands out as one of the most intriguing objects in our Milky Way. A pair of oppositely directed beams of plasma ("jets") spirals away perpendicularly from the binary system at just over a quarter of the speed of light. Using H.E.S.S. we succeeded in detecting very high energy gamma rays from the jets of SS 433, and identifying the exact location within the jets of one of the galaxy's most effective particle accelerators. Through comparison of gamma-ray images at different energies, we were able to estimate the speed of the jet far from its launch site for the first time, constraining the mechanism that is accelerating the particles so efficiently. These findings were published in Science; see also our press release.

Final Results of GERDA on the search for neutrinoless double-β decay

The final result of the world-leading GERDA detector on the search for neutrino-less double beta decay were published in PRL in December 2020. The motivation for the search is the question if neutrinos are identical with their antiparticles: a property that could boost our understanding of the matter-antimatter asymmetry of the universe. See also our press release. The successor to GERDA is the LEGEND project.