Models of multi-messenger source of cosmic rays, gamma-rays and neutrinos

Cosmic rays up to knee energy around 4 PeV, at which their spectrum sharply steepens, are believed to be produced in Milky Way Galaxy from supernovae explosions. Recently it was understood that the large scale magnetic field of the Galaxy plays crucial role in the anisotropic diffusion of cosmic rays and helps them to escape from the Galaxy. Such anisotropic diffusion leads to a much smaller number of sources contributing locally. Furthermore, only a small fraction of supernovae can accelerate to PeV energies. Together with anisotropic diffusion this leads to significant or even dominated contribution of individual sources to local cosmic ray spectrum around the knee. We model the contribution of the nearest young supernova remnant Vela to the local CRs flux taking into account both the influence of the Local Bubble and the effect of anisotropic diffusion. We found that the magnetic field in the bubble wall prevents low-energy particles penetrate into the bubble, leading to an energy-dependent suppression of CRs from Vela inside the bubble. We recovered the knee observed in the CRs spectrum of energy 3-5 PeV. By the contribution of Vela and an older local source of 2-3 Myr supernova we were able to explain the CRs spectrum from TeV to 100 PeV. Then, We studied secondary neutrinos and gamma rays produced by interaction of cosmic rays with energies up to PeV in the wall of the Local Bubble. We show that such a scenario can generate a substantial fraction of the observed astrophysical high-energy neutrino flux below ∼ few x 100 TeV. Finally, we extend our study to all other young supernovae remnants at less than 1 kpc from us. We calculated the CRs density around each source, assuming anisotropic diffusion. We used recent models of dust distribution in the local ISM extracted from extinction studies of Gaia data. Combining the obtained CRs densities with the matter distribution deduced from extinction maps, we found two prominent hot spots: One of them is close to the highest intensity hot spot in IceCube 10 years data. (author)