  We studied the effect of an external magnetic field on the angular
distributions and the linear polarizations of emissions from the
$2s^22p^53s~^3P^o_2$ state in Ne-like ions. Since a B-dependent E1 decay
channel is opened by the magnetic field and competes with the inherent M2
transition, the angular distributions and the linear polarizations strongly
depend on the magnetic field strength (B). As an example, we illustrated the
effect in Ne-like Mg. The B-dependent angular distributions and linear
polarization degrees can also be considered as a tool for diagnostics of the
magnetic field in plasmas.

Atomic Physics