Mapping The Surface of Pulsating Magnetic Stars with Zeeman- Doppler Imaging

Zeeman-Doppler Imaging (ZDI) is a technique that inverts a series of spectropolarimetric data allowing the reconstruction of the magnetic geometry and field strength of a star. It has proved to be a powerful tool in understanding the complexity and configuration of stellar magnetic fields. However, up until this point, it has been performed on the assumptions that the star has a surface brightness distribution that is constant with time and the line profiles can be modelled with a Gaussian or Voigt profile. These are not valid assumptions for pulsating stars and can lead to errors in the magnetic field strength and geometry. By modelling the pulsations observed by space photometry missions such as TESS, Kepler, BRITE and in the future, PLATO, we can integrate their additional effects into new time-dependent surface brightness maps and synthetic line profiles to fit spectropolarimetric observations. This modification of the open source ZDI code of Folsom et al. (2018) leads to improved accuracy in stellar and magnetic properties, allowing us to perform a rigorous analysis of magneto-asteroseismic data, an essential step in the magneto-asteroseismic modelling of the internal structure of stars. I will present the new ZDI code for pulsators I developed and the improvements of the results with respect to standard ZDI.