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arXiv · 0807.4221

The impact of the oblateness of Regulus on the motion of its companion

Lorenzo Iorio
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Abstract

The fast spinning B-star Regulus has recently been found to be orbited by a fainter companion in a close circular path with orbital period P_b = 40.11(2) d. Being its equatorial radius R_e 32% larger than the polar one R_p, Regulus possesses a remarkable quadrupole mass moment Q. We investigate the effects of Q on the orbital period P_b of its companion in order to see if they are measurable, given the present-day level of accuracy in measuring P_b. Conversely, we will look for deviations from the third Kepler law, attributed to the quadrupole mass moment Q of Regulus, to constrain the ratio γ=m/M of the system's masses.

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BibTeXRIS

Lorenzo Iorio. 2008-08-20. The impact of the oblateness of Regulus on the motion of its companion. https://doi.org/10.1007/s10509-008-9889-1

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