CARDILLO , MARTINAMARTINACARDILLOAMATO, ElenaElenaAMATOBlasi, PasqualePasqualeBlasi2020-03-272020-03-2720151824-8039http://hdl.handle.net/20.500.12386/23622One of the most important challenges for the largely accepted idea that Galactic CRs are acceler- ated in SNR shocks is the maximum energy at which particles can be accelerated. The resonant streaming instability, long invoked for magnetic field amplification at shocks, can not provide suf- ficiently high fields and efficient enough scattering so as to ensure particle acceleration up to the knee. Here we discuss the non-resonant version of this instability which, with its faster growth and larger value of the amplified field, increases the achievable maximum energy. Because of their higher explosion rate, we focus on type II SNe expanding in their red supergiant wind and we find that the transition between Ejecta Dominated (ED) and Sedov-Taylor (ST) phases takes place at very early times. In this environment, the accelerated particle spectrum shows no high energy exponential cut-off but a spectral break at the maximum energy (EM). Moreover, the maximum energy of protons can easily reach PeV energies. With this model, we tried to fit KASCADE- Grande and ARGO -YBJ data but failed to find a parameter combination that can explain both data sets. We discuss the different scenarios implied by the two data sets.ELETTRONICOenConference paper10.22323/1.236.0531https://pos.sissa.it/236/5312015ICRC...34..531CFIS/05 - ASTRONOMIA E ASTROFISICAScienze Fisiche Settori ERC (ERC) di riferimento::PE9 Universe sciences: astro-physics/chemistry/biology; solar systems; stellar, galactic and extragalactic astronomy, planetary systems, cosmology, space science, instrumentation