Galactic TeV Gamma-Ray Astronomy with H.E.S.S.
Dr. Kathrin Valerius (Universität Erlangen)

Among the broad spectrum of electromagnetic radiation which is being used in astrophysical observations today, very-high-energy (VHE; E>100 GeV) gamma-rays were among the latest domains to become accessible to large-scale observatories. Ground-based gamma-ray astronomy makes use of Imaging Air Cherenkov Telescopes (IACTs), which exploit the fact that the Earth ′s atmosphere is opaque to gamma radiation. In this technique, the faint flashes of Cherenkov light emitted by the charged secondary particles in gamma-ray induced air showers are recorded. The current generation of observatories employs stereoscopic imaging of the air showers to measure direction, energy and abundance of the primary gamma-rays. In the few years since these instruments became available, the number of known VHE gamma-ray sources has risen from about a handful to well more than 100. The majority of these sources are found within our own Galaxy.

Situated in the southern hemisphere and equipped with a large field of view, the High Energy Stereoscopic System (H.E.S.S.), an array of four IACTs, is ideally suited to study VHE gamma-ray sources in the Milky Way. During an extensive survey campaign of the Galactic Plane, more than 50 objects belonging to different source classes were discovered, with pulsar wind nebulae and supernova remnants forming the most numerous populations. In this talk, a few examples of such Galactic VHE gamma-ray emitters, which begin to unveil to us an image of the Milky Way at the highest energies, will be presented.