Cherenkov Telescope Array Observatory sensitivity to heavy Galactic Cosmic Rays and the shape of particle spectrum
Year: 2025
Type: article
Abstract: The origin of Galactic Cosmic Rays (GCRs) and the potential role of Supernova Remnants (SNRs) as cosmic-ray (CR) accelerators remain subjects of ongoing debate. To shed more light on this topic, we have studied the spectral shapes of two SNRs, RX J1713.7-3946 and HAWC J2227+610, performing simulations for the Cherenkov Telescope Array Observatory (CTAO). The previous multi-wavelength (MWL) analysis on these two sources showed an important hadronic contribution at high energies. The interaction of the GCRs accelerated by the SNRs with the medium around the accelerator leads to a process of pion decay (PD) that produces gamma-rays (γ-rays). These emissions, detectable by CTAO, offer an indirect means of pinpointing the CR source. Two scenarios have been considered: the contribution of heavy CRs and different cut-off sharpnesses (β) of the particle spectra. The simulations were performed by using different CR composition distributions (protons, CNO, Fe) and different sharpness values ranging from β = 0.5 to β = 1.5. The results show that, in the cases studied here, CTAO will increase the sensitivity to the spectral shape of γ-rays. This allows us to distinguish protons from heavy CRs and obtain information on β values and therefore on different acceleration scenarios.
Authors: C. Dubos, P. Sharma, S. Patel, T. Suomijärvi
Institutions: Centre National de la Recherche Scientifique, Université Paris-Saclay, Institut National de Physique Nucléaire et de Physique des Particules, Laboratoire de Physique des 2 Infinis Irène Joliot-Curie, Observatoire astronomique de Strasbourg, Université de Strasbourg, Helmholtz-Zentrum Berlin für Materialien und Energie
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4408055380