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Kepler Planet Occurrence Rates for Mid-Type M Dwarfs as a Function of Spectral Type

Hardegree-Ullman, Kevin Karlyle
http://orcid.org/0000-0003-3702-0382
http://rave.ohiolink.edu/etdc/view?acc_num=toledo1533214839813619

Abstract Details

2018, Doctor of Philosophy, University of Toledo, Physics.
Previous studies of planet occurrence rates largely relied on photometric stellar characterizations. We present spectroscopic observations of 337 out of 561 probable mid-type M dwarfs in the primary Kepler field. Our observations have allowed us to constrain spectral type, temperatures, and in some cases metallicities for these stars. We use a random forest classifier to spectral type the remaining 224 targets. Combining our data with Gaia parallaxes, we have computed precise (~3%) stellar radii, which we use to update planet parameters and planet occurrence rates for Kepler mid-type M dwarfs. Within the Kepler field, there are seven M3 V to M5 V stars which host a total of 13 confirmed planets between 0.5 and 2.5 Earth radii and at orbital periods between 0.5 and 10 days. For this population, we compute a planet occurrence rate of 1.27+0.14-0.28 planets per star. With our spectral classifications, we compute planet occurrence rates for each spectral sub-type which yields 0.78+0.53-0.40, 1.23+1.14-0.75, and 2.51+2.87-1.51 planets per star for M3 V, M4 V, and M5 V, respectively. Our updated planet parameters show Kepler-1649 b to be an Earth sized planet receiving insolation flux similar to Earth. We also use our data to compute stellar mass, identify active stars with Hα emission, and identify binary candidates. Our observations with the multi-object spectrograph Hydra on the WIYN telescope allowed us to observe 1,083 other Kepler stars, which will be useful in future studies.
Michael Cushing (Committee Chair)
Jon Bjorkman (Committee Member)
Rupali Chandar (Committee Member)
Philip Muirhead (Committee Member)
Nikolas Podraza (Committee Member)
207 p.
Astronomy; Astrophysics; Physics
planet occurrence rates; exoplanets; M dwarfs; stars; stellar spectra; stellar classification; planets; Kepler; Gaia; WIYN; DCT; IRTF; LAMOST; transiting exoplanets

Recommended Citations

Citations

  • Hardegree-Ullman, K. K. (2018). Kepler Planet Occurrence Rates for Mid-Type M Dwarfs as a Function of Spectral Type [Doctoral dissertation, University of Toledo]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1533214839813619

    APA Style (7th edition)

  • Hardegree-Ullman, Kevin. Kepler Planet Occurrence Rates for Mid-Type M Dwarfs as a Function of Spectral Type. 2018. University of Toledo, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=toledo1533214839813619.

    MLA Style (8th edition)

  • Hardegree-Ullman, Kevin. "Kepler Planet Occurrence Rates for Mid-Type M Dwarfs as a Function of Spectral Type." Doctoral dissertation, University of Toledo, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1533214839813619

    Chicago Manual of Style (17th edition)

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This open access ETD is published by University of Toledo and OhioLINK.