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First results of a magnetic survey of classical Cepheids

Published online by Cambridge University Press:  29 August 2024

James A. Barron*
Affiliation:
Department of Physics, Engineering Physics & Astronomy, Queen’s University, Canada Department of Physics and Space Science, Royal Military College of Canada
Gregg A. Wade
Affiliation:
Department of Physics and Space Science, Royal Military College of Canada
Colin P. Folsom
Affiliation:
Tartu Observatory, University of Tartu, Estonia
Oleg Kochukhov
Affiliation:
Department of Physics and Astronomy, Uppsala University, Sweden
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Abstract

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We report recent ESPaDOnS and HARPSpol spectropolarimetric observations from our ongoing magnetic survey of the brightest twenty-five classical Cepheids. Stokes V magnetic signatures are detected in eight of fifteen targets observed to date. The Stokes V profiles show a diversity of morphologies with weak associated longitudinal field measurements of order 1 G. Many of the Stokes V profiles are difficult to interpret in the context of the normal Zeeman effect. They consist of approximately unipolar single or double lobe(s) of positive or negative circular polarization. We hypothesize that these unusual signatures are due to the Zeeman effect modified by atmospheric velocity or magnetic field gradients. In contrast, the Stokes V profiles of Polaris and MY Pup appear qualitatively similar to the complex magnetic signatures of non-pulsating cool supergiants, possibly due to the low pulsation amplitudes of these two stars.

Type
Poster Paper
Copyright
© The Author(s), 2024. Published by Cambridge University Press on behalf of International Astronomical Union

References

Anderson, R. I. 2019, A&A, 623, A146 Google Scholar
Anderson, R. I., Saio, H., Ekström, S., Georgy, C., & Meynet, G. 2016, A&A, 591, A8 Google Scholar
Barron, J. A., Wade, G. A., Evans, N. R., Folsom, C., & Neilson, H. R. 2022, MNRAS, 512, 4021 Google Scholar
Georgy, C., et al. 2013, A&A, 553, A24 CrossRefGoogle Scholar
Grunhut, J. H., Wade, G. A., Hanes, D. A., & Alecian, E. 2010, MNRAS, 408, 2290 Google Scholar
Kienzle, F., Moskalik, P., Bersier, D., & Pont, F. 1999, A&A, 341, 818 Google Scholar
Luck, R. E. 2018, AJ, 156, 171 Google Scholar
Petit, P., et al. 2011, A&A, 532, L13 Google Scholar
Riess, A. G., et al. 2021, arXiv e-prints, arXiv:2112.04510Google Scholar
Turner, D. G. 2010, AP&SS, 326, 219 CrossRefGoogle Scholar
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