| Abstract : | I will be presenting the mode analysis to model the mean large-scale Galactic magnetic field (GMF) structure of the M31 galaxy. Earlier analysis using the multi-wavelength data (6, 11, and 20 cm) from Effelsberg 100m telescope indicates that only the axisymmetric large-scale GMF field (mode 0) is enough to model the outer rings from 8-14 kpc while a weak quadri-symmetric term (mode 2) is present along with the dominant axisymmetric field for the inner ring (6-8 kpc). We have used the recent radio continuum data at 3, 6, 11 and 20 cm wavelength and find sub-dominant contributions from other higher modes (modes 1, 2, 3 and 4) along with the dominant axisymmetric term. The modeling results show that the rotation measure of Milky Way (RM_{fg}) and the pitch angle (p_0) are consistent over all the rings while the strength of the magnetic field is maximum for the radial ring of 10-12 Kpc suggesting the presense of bright radio ring of M31 at around 11 Kpc. |
