The origin of  very high energy astrophysical neutrinos recently discovered by IceCube experiment  at South Pole is still unknown.

Both Galactic and extragalactic astrophysical sources accelarate high energy  cosmic rays
up enormous energies 10**(11) GeV, which is in 10 000 000 larger energy compared to one ever achived by humans on Large Hadronic Collider. However even such high energy cosmic rays
 are strongly deflected by Galactic and extragalactic magnetic fields before they reach detector on Earth. This does not allow to find their origin for already more then 100 years.

In the dense background near their sources cosmic rays produce secondary gamma-rays and neutrinos. Gamma-rays  loose energy in interaction with CMB, infrared and optical backgrounds  before beeing observed on the Earth  and only ultra-high energy neutrinos
can reach us directly from their production cites.

Goal of thesis will be the modeling of sources of cosmic rays, gamma rays and neutrinos taking into account all experimental constraints from direct measurements, KASCADE-Grande and Pierre Auger Observatory for cosmic rays, HESS, Fermi and CTA for gamma-rays and ICECUBE/km3 for neutrinos, study propagation of cosmic rays and gamma-rays in the Galaxy and intergalactic space, search for the imprints of such sources in the experimental data.

Part of the thesis will be development of both galactic and extragalactic models
of multi-messenger sources, which obey all existing measurements and
make predictions for future experiments.