Promotionsvortrag Physik: „Improvements to event reconstruction and analysis of IACT data and their application to joint-instrument analyses of galactic and extragalactic gamma-ray sources“

Ankündigung des Promotionsvortrags von: Herrn Tim Unbehaun

Imaging Atmospheric Cherenkov Telescopes (IACTs) detect γ-ray-induced particle showers and have revealed numerous extreme particle accelerators, from pulsar wind nebulae to active galactic nuclei. Yet, the composition and acceleration mechanisms remain uncertain. Reconstructing inci-dent particle properties is challenging, especially for monoscopic events. This work introduces a variable event-selection cut, novel image parameters, and an orientation algorithm that improve reconstruction accuracy, sensitivity, and energy thresholds, while enhancing particle-type classifi-cation to separate γ rays from cosmic-ray background. These methods are applied to Crab Nebula data with systematic effects quantified on simulations. For spectral analyses, two schemes correct background asymmetries, while unbinned likelihood methods avoid information loss and improve studies of variable sources such as pulsars, with implementations explored in Gammapy. Joint γ-ray–neutrino analyses with CTAO and KM3NeT simulations demonstrate sensitivity to leptonic vs. hadronic scenarios and extend Gammapy to neutrino data. Multi-instrument studies of the Crab Nebula achieve the first fully self-consistent γ-ray analysis across five decades in energy, con-straining its spectrum, extension, and magnetic-field profile. A combined Fermi-LAT and H.E.S.S. analysis of Centaurus A confirms a hardening in the core spectrum ab

(Vortrag auf Englisch)

Dem Vortrag schließt sich eine Diskussion von 15 Minuten an. Vortrag und Diskussion sind öffentlich. Diesen Verfahrensteilen folgt ein nicht öffentliches Rigorosum von 45 Minuten.