Abstract:
First, I present the results of an independent search of all ~200,000 stars observed over the four-year Kepler mission for multi-planet systems, using a three-transit minimum detection criteria to search orbital periods up to hundreds of days. My search returned 17 new planet candidates, in addition to thousands of known Kepler Objects of Interest (KOIs), with a 98.8% recovery rate of already confirmed planets. I highlight the discovery of one candidate, KIC-7340288 b, that is both rocky (radius <1.6 R_Earth) and in the Habitable Zone (insolation between 0.25 and 2.5 times the Earth's insolation). Another candidate is an addition to the already known KOI-4509 system. I also present adaptive optics imaging follow up for 6 of my new planet candidates, 2 of which reveal a line-of-sight stellar companion within 4".
Using my independent Kepler planet catalogue, I then present exoplanet occurrence rates estimated with approximate Bayesian computing for planets with radii between 0.5 - 16 R_Earth and orbital periods between 0.78 - 400 days days, orbiting FGK dwarf stars. I characterize the efficiency of planet recovery by both my search and vetting pipelines using injection/recovery tests, and account for both planet radius uncertainty and the estimated false positive rate due to transit-like noise signals in the data. Marginalizing over the entire period-radius space, I find ~1 planet per FGK star. By analyzing my FGK occurrence rates as well as those computed after separating F, G, and K type stars, I explore dependencies on stellar effective temperature, planet radius, and orbital period.
Finally, I provide several estimates of the ``eta-Earth'' value --- the frequency of potentially habitable, rocky planets orbiting Sun-like stars. For planets with sizes 0.75 - 1.5 R_Earth orbiting in a conservatively defined Habitable Zone (0.99 - 1.70 AU) around G type stars, my reliability-incorporated calculations place an upper limit (84.1th percentile) of < 0.18 planets per star.
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2020-04-14T12:30:002020-04-14T15:30:00"Searching the Entirety of Kepler Data: New Exoplanets and Occurrence Rate Estimates”Event Information:
Final PhD Oral Examination
Abstract:
First, I present the results of an independent search of all ~200,000 stars observed over the four-year Kepler mission for multi-planet systems, using a three-transit minimum detection criteria to search orbital periods up to hundreds of days. My search returned 17 new planet candidates, in addition to thousands of known Kepler Objects of Interest (KOIs), with a 98.8% recovery rate of already confirmed planets. I highlight the discovery of one candidate, KIC-7340288 b, that is both rocky (radius <1.6 R_Earth) and in the Habitable Zone (insolation between 0.25 and 2.5 times the Earth's insolation). Another candidate is an addition to the already known KOI-4509 system. I also present adaptive optics imaging follow up for 6 of my new planet candidates, 2 of which reveal a line-of-sight stellar companion within 4".
Using my independent Kepler planet catalogue, I then present exoplanet occurrence rates estimated with approximate Bayesian computing for planets with radii between 0.5 - 16 R_Earth and orbital periods between 0.78 - 400 days days, orbiting FGK dwarf stars. I characterize the efficiency of planet recovery by both my search and vetting pipelines using injection/recovery tests, and account for both planet radius uncertainty and the estimated false positive rate due to transit-like noise signals in the data. Marginalizing over the entire period-radius space, I find ~1 planet per FGK star. By analyzing my FGK occurrence rates as well as those computed after separating F, G, and K type stars, I explore dependencies on stellar effective temperature, planet radius, and orbital period.
Finally, I provide several estimates of the ``eta-Earth'' value --- the frequency of potentially habitable, rocky planets orbiting Sun-like stars. For planets with sizes 0.75 - 1.5 R_Earth orbiting in a conservatively defined Habitable Zone (0.99 - 1.70 AU) around G type stars, my reliability-incorporated calculations place an upper limit (84.1th percentile) of < 0.18 planets per star.Event Location:
UBC’s Virtual Meeting Room (VMR)