Magnetic fields in the Milky Way neighbouhood as deduced from WARPS in inspiral galaxies

Abstract

It is shown that warps of spiral galaxies are not randomly oriented in the Milky Way neighbourhood. By adopting a previous model, in which warps are produced by intergalactic magnetic fields, and considering all northern hemisphere warped edge-on NGC spiral galaxies, an analysis of the intergalactic magnetic field in the 100 Mpc neighbourhood of our Galaxy is carried out. At the 100 Mpc scale the magnetic field is still rather homogeneous, having a direction given by (alpha = 289 degrees, delta = 8 degrees), but a characteristic scale of about 25 Mpc is found, inside which the dispersion is very low. The region containing the Virgo Cluster has a direction of the magnetic field different from the direction found in adjacent regions.