Displacement of ultra-high-energy cosmic ray source images by the intergalactic magnetic field: the cases of Cen A and M83

Understand

The standard assumption about the influence of the turbulent intergalactic magnetic field (IGMF) on the images of ultra-high-energy cosmic rays (UHECR) sources is that the latter are formed in a random walk mode in the deflection angle.

• As a result, the images are symmetrically broadened to angular scales proportional to the IGMF strength and the square root of its correlation length.
• We demonstrate that when the size of the emitting region is smaller than the correlation length of the IGMF, a new focusing regime emerges.
• In this regime, significant deviations from the standard random walk approximation occur even when the distance between the source and the observer exceeds several tens of IGMF correlation lengths.