https://doi.org/10.1051/epjconf/202531905001
Exploring NGC 3603 non-thermal emission through a realistic modelling of its environment
1 Universität Innsbruck, Institut für Astro- und Teilchenphysik, Technikerstr. 25/8, 6020 Innsbruck, Austria
2 Dipartimento di Fisica, Universitá di Trieste, I-34127 Trieste, Italy
3 Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, 34127 Trieste, Italy
* e-mail: manuel.rocamora@uibk.ac.at
Published online: 6 March 2025
We study the young and compact star-forming region NGC 3603, a well known γ-ray emitter. We build a novel non-thermal emission model by creating realistic 3D distributions of the gas and the radiation field in the region. We introduce these models into PICARD to perform cosmic-ray transport simulations and produce emission maps. The results are compared with a dedicated Fermi Large Area Telescope data analysis at high energies and with ATCA radio data. We improve the existing upper limits of the NGC 3603 γ-ray source extension. Although the γ-ray spectrum is well reproduced with the injection of CR protons, the resulting extension of the simulated hadronic source is in mild tension with the data upper limit. The radio data disfavours the lepton-only scenario. Combining both cosmic-ray populations the results are consistent with all observables.
© The Authors, published by EDP Sciences, 2025
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
