Binaries Escorted By Orbiting Planets

Monday 2 July, 17:20

Circumbinary planets provide a key population to further our understanding of the processes behind planet formation. Comparing the properties of circumbinary planets to planets orbiting single stars will uncover how planets manage to assemble and migrate in an environment where there are two stars instead of one. Circumbinary planets are able to test our theories regarding planet formation.

Only two handful of circumbinary planets are known, mostly identified by Kepler. However, the transit method has severe limitations meaning that most circumbinary planets in the Kepler field remained undetected. Radial-velocities can provide a more complete and accurate picture of that important population, but initial surveys were hindered when it was found that the presence of two stellar spectra interfered with observations. 

We can circumvent this problem by surveying single-line binaries, composed of a Sun-like star, and a late M dwarf. I will present HARPS observations demonstrating that circumbinary planets the mass of Neptune can be detected. I will also describe the BEBOP programme, the first comprehensive survey of single-line eclipsing binaries, started on CORALIE, and currently continuing as a large programme on HARPS. 

 

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