On the origin of galactic cosmic rays

• Jet’s past activity explains the origin of cosmic rays in the Galaxy.
• Bubbles are remnants of the bipolar jet.
• Estimated time of switching on of the jet is 2.4·1072.4·107 years ago.

It is shown that the relativistic jet, emitted from the center of the Galaxy during its activity, possessed power and energy spectrum of accelerated protons sufficient to explain the current cosmic rays distribution in the Galaxy. Proton acceleration takes place on the light cylinder surface formed by the rotation of a massive black hole caring into rotation the radial magnetic field and the magnetosphere. Observed in gamma, X-ray and radio bands bubbles above and below the galactic plane can be remnants of this bipolar get. The size of the bubble defines the time of the jet’s start, ≃2.4·107≃2.4·107 years ago. The jet worked more than 107107 years, but less than 2.4·1072.4·107 years.