We discuss a specific population of galactic PeVatrons which may be the mainsource of the galactic cosmic-ray (CR) component well above PeV energies.Supernovae in compact clusters of massive stars are proposed as powerfulsources of CRs, neutrinos, and gamma-ray emission. Numerical simulations ofnon-linear Fermi acceleration at converging shock flows have revealed thatthese accelerators can provide very hard spectra of protons up to$10^{16}-10^{17}$ eV which is well above the "knee" in the all-particle CRspectrum at about $3\times10^{15}$ eV. We suggest that known supernova remnantsinteracting with stellar winds in the compact clusters of young massive starsWesterlund I and Cl*1806-20 can be associated with the sources of the TeVgamma-ray emission detected by H.E.S.S. and may be responsible for a fractionof the high-energy neutrinos detected with the IceCube observatory. A recent CRcomposition measurement with the LOFAR array has revealed a light-masscomponent possibly dominating the all-particle spectrum at energies around$10^{17}$ eV. Such a strong light component (mainly protons and helium) mayrequire specific galactic CR sources such as supernovae interacting withcompact clusters of massive stars in addition to isolated supernova remnants.
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