Speckle Observations of TESS Exoplanet Host Stars: Understanding the Binary Exoplanet Host Star Orbital Period Distribution. (arXiv:2101.08671v1 [astro-ph.EP])

Speckle Observations of TESS Exoplanet Host Stars: Understanding the Binary Exoplanet Host Star Orbital Period Distribution. (arXiv:2101.08671v1 [astro-ph.EP])
<a href="http://arxiv.org/find/astro-ph/1/au:+Howell_S/0/1/0/all/0/1">Steve B. Howell</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Matson_R/0/1/0/all/0/1">Rachel A. Matson</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ciardi_D/0/1/0/all/0/1">David R. Ciardi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Everett_M/0/1/0/all/0/1">Mark E. Everett</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Livingston_J/0/1/0/all/0/1">John H. Livingston</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Scott_N/0/1/0/all/0/1">Nicholas J. Scott</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Horch_E/0/1/0/all/0/1">Elliott P. Horch</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Winn_J/0/1/0/all/0/1">Joshua N. Winn</a>

We present high-resolution speckle interferometric imaging observations of
TESS exoplanet host stars using the NN-EXPLORE NESSI instrument the at the
3.5-m WIYN telescope. Eight TOIs, that were originally discovered by Kepler,
were previously observed using the Differential Speckle Survey Instrument
(DSSI). Speckle observations of 186 TESS stars were carried out and 45 (24%)
likely bound companions were detected. This is approximately the number of
companions we would expect to observe given the established 46% binarity rate
in exoplanet host stars. For the detected binaries, the distribution of stellar
mass ratio is consistent with that of the standard Raghavan distribution and
may show a decrease in high-q systems as the binary separation increases. The
distribution of binary orbital periods, however, is not consistent with the
standard Ragahavan model and our observations support the premise that
exoplanet-hosting stars with binary companions have, in general, wider orbital
separations than field binaries. We find that exoplanet-hosting binary star
systems show a distribution peaking near 100 au, higher than the 40-50 au peak
that is observed for field binaries. This fact led to earlier suggestions that
planet formation is suppressed in close binaries.

We present high-resolution speckle interferometric imaging observations of
TESS exoplanet host stars using the NN-EXPLORE NESSI instrument the at the
3.5-m WIYN telescope. Eight TOIs, that were originally discovered by Kepler,
were previously observed using the Differential Speckle Survey Instrument
(DSSI). Speckle observations of 186 TESS stars were carried out and 45 (24%)
likely bound companions were detected. This is approximately the number of
companions we would expect to observe given the established 46% binarity rate
in exoplanet host stars. For the detected binaries, the distribution of stellar
mass ratio is consistent with that of the standard Raghavan distribution and
may show a decrease in high-q systems as the binary separation increases. The
distribution of binary orbital periods, however, is not consistent with the
standard Ragahavan model and our observations support the premise that
exoplanet-hosting stars with binary companions have, in general, wider orbital
separations than field binaries. We find that exoplanet-hosting binary star
systems show a distribution peaking near 100 au, higher than the 40-50 au peak
that is observed for field binaries. This fact led to earlier suggestions that
planet formation is suppressed in close binaries.

http://arxiv.org/icons/sfx.gif

Comments are closed.