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arXiv · 1410.4063

The origin of Cosmic-Rays from SNRs: confirmations and challenges after the first direct proof

M. Cardillo·M. Tavani·A. Giuliani
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Abstract

Until now, providing an experimental unambiguous proof of Cosmic Ray (CR) origin has been elusive. The SuperNova Remnant (SNR) study showed an increasingly complex scenario with a continuous elaboration of theoretical models. The middle-aged supernova remnant (SNR) W44 has recently attracted attention because of its relevance regarding the origin of Galactic cosmic-rays. The gamma-ray missions AGILE and Fermi have established, for the first time for a SNR, the spectral continuum below 200 MeV which can be attributed to neutral pion emission. Our work is focused on a global re-assessment of all available data and models of particle acceleration in W44 and our analysis strengthens previous studies and observations of the W44 complex environment, providing new information for a more detailed modeling. However, having determined the hadronic nature of the gamma-ray emission on firm ground, a number of theoretical challenges remains to be addressed in the context of CR acceleration in SNRs.

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M. Cardillo, M. Tavani, A. Giuliani. 2014-10-15. The origin of Cosmic-Rays from SNRs: confirmations and challenges after the first direct proof. https://doi.org/10.1016/j.nuclphysbps.2014.10.007

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