  49 Cam is a cool magnetic chemically peculiar star which has been noted for
showing strong, complex Zeeman linear polarisation signatures. This paper
describes magnetic and chemical surface maps obtained for 49 Cam using the
INVERS10 magnetic Doppler imaging code and high-resolution spectropolarimetric
data in all four Stokes parameters collected with the ESPaDOnS and Narval
spectropolarimeters at the Canada-France-Hawaii Telescope and Pic du Midi
Observatory. The reconstructed magnetic field maps of 49 Cam show a relatively
complex structure. Describing the magnetic field topology in terms of spherical
harmonics, we find significant contributions of modes up to l=3, including
toroidal components. Observations cannot be reproduced using a simple low-order
multipolar magnetic field structure. 49 Cam exhibits a level of field
complexity that has not been seen in magnetic maps of other cool Ap stars.
Hence we concluded that relatively complex magnetic fields are observed in Ap
stars at both low and high effective temperatures. In addition to mapping the
magnetic field, we also derive surface abundance distributions of nine chemical
elements, including Ca, Sc, Ti, Cr, Fe, Ce, Pr, Nd, Eu. Comparing these
abundance maps with the reconstructed magnetic field geometry, we find no clear
relationship of the abundance distributions with the magnetic field for some
elements. However, for other elements some distinct patterns are found. We
discuss these results in the context of other recent magnetic mapping studies
and theoretical predictions of radiative diffusion.
