next previous
Up: No magnetic field variations  Aquilae


6 Conclusions

New MuSiCoS circular polarisation observations and ultra-high precision determinations of the longitudinal magnetic field of the Cepheid variable $\eta $ Aql show no convincing evidence of a photospheric magnetic field. This result is in agreement with measurements by Borra et al. (1981), and in conflict with recent claims by Plachinda (2000). At present, the simplest conclusion is that $\eta $ Aql is a non-magnetic star, at least at the level of $\sim $10 G.

Acknowledgements

This work has taken advantage of the Vienna Atomic Line Database (VALD). GAW acknowledges grant support from the Natural Sciences and Engineering Research Council of Canada, and the Canadian Department of National Defence. WWW acknowledges support by the Fonds zur Förderung der wissenschaftlichen Forschung (P14984) and the Hochschuljubiläumsstiftung der Stadt Wien. We also acknowledge the referee, C. Johns-Krull, for useful comments leading to the improvement of this manuscript.


next previous
Up: No magnetic field variations  Aquilae

Copyright ESO 2002