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arXiv · 1009.4083

Discovery of a strong magnetic field in the rapidly rotating B2Vn star HR 7355

M. E. Oksala·G. A. Wade·W. L. F. Marcolino·J. Grunhut·D. A. Bohlender·N. Manset·R. H. D. Townsend·the MiMeS Collaboration
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Abstract

We report on the detection of a strong, organized magnetic field in the helium-variable early B-type star HR 7355 using spectropolarimetric data obtained with ESPaDOnS on CFHT by the MiMeS large program. We also present results from new V-band differential photometry obtained with the CTIO 0.9m telescope. We investigate the longitudinal field, using a technique called Least-Squares Deconvolution (LSD), and the rotational period of HR 7355. These new observations strongly support the proposal that HR 7355 harbors a structured magnetosphere similar to that in the prototypical helium-strong star, sigma Ori E.

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M. E. Oksala, G. A. Wade, W. L. F. Marcolino, J. Grunhut, D. A. Bohlender, N. Manset, R. H. D. Townsend, the MiMeS Collaboration. 2010-09-21. Discovery of a strong magnetic field in the rapidly rotating B2Vn star HR 7355. https://doi.org/10.1017/s1743921311010350

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