# The importance of non-photon noise in stellar spectropolarimetry. The spurious detection of a non-existing magnetic field in the A0 supergiant HD 92207

@article{Bagnulo2013TheIO,
title={The importance of non-photon noise in stellar spectropolarimetry. The spurious detection of a non-existing magnetic field in the A0 supergiant HD 92207},
author={Stefano Bagnulo and Luca Fossati and Oleg Kochukhov and John D. Landstreet},
journal={arXiv: Instrumentation and Methods for Astrophysics},
year={2013}
}
• Published 9 September 2013
• Physics, Geology
• arXiv: Instrumentation and Methods for Astrophysics
The low-resolution, Cassegrain mounted, FORS spectropolarimeter of the ESO Very Large Telescope is being extensively used for magnetic field surveys. Some of the new discoveries suggest that relatively strong magnetic fields may play an important role in numerous physical phenomena observed in the atmospheres as well as in the circumstellar environments of certain kinds of stars. We show in detail how small instabilities or data-reduction inaccuracies represent an alternative explanation for…

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