Accounting for Incompleteness due to Transit Multiplicity in Kepler Planet Occurrence Rates. (arXiv:1901.00196v1 [astro-ph.EP])
<a href="http://arxiv.org/find/astro-ph/1/au:+Zink_J/0/1/0/all/0/1">Jon K. Zink</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Christiansen_J/0/1/0/all/0/1">Jessie L. Christiansen</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hansen_B/0/1/0/all/0/1">Bradley M. S. Hansen</a>
We investigate the role that planet detection order plays in the Kepler
planet detection pipeline. The Kepler pipeline typically detects planets in
order of descending signal strength (MES). We find that the detectability of
transits experiences an additional $5.5%$ and $15.9%$ efficiency loss, for
periods $<200$ days and $>200$ days respectively, when detected after the
strongest signal transit in a multiple-planet system. We provide a method for
determining the transit probability for multiple-planet systems by
marginalizing over the empirical Kepler dataset. Furthermore, because detection
efficiency appears to be a function of detection order, we discuss the sorting
statistics that affect the radius and period distributions of each detection
order. Our occurrence rate dataset includes radius measurement updates from the
California Kepler Survey (CKS), Gaia DR2, and asteroseismology. Our population
model is consistent with the results of Burke et al. (2015), but now includes
an improved estimate of the multiplicity distribution. From our obtained model
parameters, we find that only $4.0pm4.6%$ of solar-like GK dwarfs harbor one
planet. This excess is smaller than prior studies and can be well modeled with
a modified Poisson distribution, suggesting that the Kepler Dichotomy can be
accounted for by including the effects of multiplicity on detection efficiency.
Using our modified Poisson model we expect the average number of planets is
$5.86pm0.18$ planets per GK dwarf within the radius and period parameter space
of Kepler.
We investigate the role that planet detection order plays in the Kepler
planet detection pipeline. The Kepler pipeline typically detects planets in
order of descending signal strength (MES). We find that the detectability of
transits experiences an additional $5.5%$ and $15.9%$ efficiency loss, for
periods $<200$ days and $>200$ days respectively, when detected after the
strongest signal transit in a multiple-planet system. We provide a method for
determining the transit probability for multiple-planet systems by
marginalizing over the empirical Kepler dataset. Furthermore, because detection
efficiency appears to be a function of detection order, we discuss the sorting
statistics that affect the radius and period distributions of each detection
order. Our occurrence rate dataset includes radius measurement updates from the
California Kepler Survey (CKS), Gaia DR2, and asteroseismology. Our population
model is consistent with the results of Burke et al. (2015), but now includes
an improved estimate of the multiplicity distribution. From our obtained model
parameters, we find that only $4.0pm4.6%$ of solar-like GK dwarfs harbor one
planet. This excess is smaller than prior studies and can be well modeled with
a modified Poisson distribution, suggesting that the Kepler Dichotomy can be
accounted for by including the effects of multiplicity on detection efficiency.
Using our modified Poisson model we expect the average number of planets is
$5.86pm0.18$ planets per GK dwarf within the radius and period parameter space
of Kepler.
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