Liquid metal experiments on the Tayler instability

In the kink-type Tayler instability (TI) a toroidal magnetic field becomes unstable against non-axisymmetric perturbations for a sufficiently large field amplitude. The TI has been discussed as a possible ingredient of the solar dynamo and a source of the helical structures in cosmic jets. It has also to be considered as a limiting criterion for the size of large scale liquid metal batteries. We report on first TI experiments with a cylindrical column of GaInSn to which electrical currents of up to 8 kA are applied. We present results of external magnetic field measurements that indicate the occurrence of the TI.