English

A Possible Spin-Orbit Misalignment in the Transiting Eccentric Planet HD 17156b

Astrophysics 2015-05-13 v2

Abstract

We present simultaneous photometric and spectroscopic observations of HD 17156b spanning a transit on UT 2007 November 12. This system is of special interest because of its 21-day period (unusually long for a transiting planet) and its high orbital eccentricity of 0.67. By modeling the Rossiter-McLaughlin effect, we find the angle between the sky projections of the orbital axis and the stellar rotation axis to be 62±2562^{\circ} \pm 25^{\circ}. Such a large spin-orbit misalignment, as well as the large eccentricity, could be explained as the relic of a previous gravitational interaction with other planets.

Keywords

Cite

@article{arxiv.0712.2569,
  title  = {A Possible Spin-Orbit Misalignment in the Transiting Eccentric Planet HD 17156b},
  author = {Norio Narita and Bun'ei Sato and Osamu Ohshima and Joshua N. Winn},
  journal= {arXiv preprint arXiv:0712.2569},
  year   = {2015}
}

Comments

5 pages, 2 figures, 3 tables. Accepted for publication in PASJ Letters (Vol. 60, No. 2)

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