Abstract
We present a work in progress aimed to study the magnetic field strength and structure in the hot cluster of galaxies A401. For this purpose we derived the rotation measure of two cluster radio sources by using Very Large Array observations at 3.6 cm and 6 cm. The data are interpreted on the basis of the expectation of a 3D cluster magnetic field model. A multi-scale magnetic field with a strength of about 4 μG at the cluster center reproduces the data quite well.
