Detection Methods and Relevance of Exoplanetary Magnetic Fields
Abstract
In analogy to the planets of the Solar System, most extrasolar planets are expected to have an intrinsic, internally generated magnetic field. These magnetic fields are believed to influence a number of physical processes, so that planets with and without fields may not behave and evolve the same way, and implications for the planet are manyfold. Clear observational evidence for such fields is however difficult to find, and no unambiguous detection has yet been achieved. Over the past few years, a number of methods have been suggested with which an exoplanetary magnetic field could be detected remotely. Some of these methods could even be used to characterize the planetary magnetic field strength quantitatively. The present work describes the different ways in which a planetary magnetic field may modify the planetary evolution and reviews the different methods that have been suggested to detect these fields. These methods are compared and we evaluate which techniques have the highest potential for future detection of exoplanetary magnetic fields.