Aachen 2019 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
T: Fachverband Teilchenphysik
T 21: Kosmische Strahlung, Propagation
T 21.7: Talk
Monday, March 25, 2019, 17:30–17:45, ST 7
Improved photo-meson model for UHECR nuclei interactions — •Leonel Morejon1, Anatoli Fedynitch1, Denise Boncioli2, Daniel Biehl1, and Walter Winter1 — 1DESY Zeuthen, Platanenallee 6, 15738 Zeuthen, Brandenmburg, Germany — 2GSSI, Via Michele Jacobucci 2, 67100 L’Aquila AQ, Italia
Photon-nucleus interactions are a necessary element in radiation models of sources and transport Ultra-High Energy Cosmic Rays (UHECRs). The UHECRs encounter dense photon fields with energies in the range µ eV − MeV which are boosted to MeV − GeV in the nucleus rest frame, prompting pion production and thus connecting cosmic rays, gamma rays and neutrino spectra. Photomeson models are used to simulate these interactions above the photopion threshold, and previous works have introduced simplifications which need improvement.
Here we introduce a new photomeson model based on experimental data which improves on the previous models. Specifically, the new model includes shadowing by including an energy dependence of the mass scaling of the total nonelastic cross section above 1 GeV; it also includes pion re-absorption in the nuclear medium by appropriately scaling the photopion cross section with the nuclear surface (∼ A2/3), and finally the model contains enhanced nuclear breakup by the inclusion of multiple disintegration channels.
The relevance of these improvements is illustrated by showing the impact on the results of simulating two proposed source classes which have been found in recent works suitable as UHECRs sources.