The Astronomy and Astrophysics journal has chosen a HESS paper, with UZH researcher as corresponding author, as an A&A Highlight; selected by A&A Editors as particularly interesting papers.
HESS (High Energy Stereoscopic System) is an array of five Cherenkov telescopes located in Namibia and is taking data since 2002. Combining data over more than ten years of HESS observations into a deep exposure on the region enabled detailed spectral and morphological analysis of the pulsar wind nebula HESS J1825-137. By characterising the extent of the gamma-ray emission in a set of independent energy bands, the changing size was used to test the mechanism of particle transport within the nebula. A spatially resolved spectral analysis into more than 40 regions enabled a spectral map of the nebula to be made.
The figure shows the excess count maps of the pulsar wind nebula HESS J1825–137 region in four different energy bands: E < 1 TeV, 1 TeV < E < 10 TeV, E > 10 TeV, and E> 32 TeV. The size of the source reduces with higher energies.