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M dwarfs, though the most abundant star in the galaxy, form only a small subset of stellar hosts with exoplanets with measured radii and masses. In this paper we analyze the Mass-Radius (M-R) relationship of planets around M dwarfs using M-R measurements for 24 exoplanets. In particular, we apply both parametric and nonparametric models and compare the two different fitting methods. We also use these methods to compare the results of the M dwarf M-R relationship with that from the Kepler sample. Using the nonparametric method, we find that the predicted masses for the smallest and largest planets around M dwarfs are smaller than that given by the relation fit to the Kepler data, but that the distribution of masses for 3 Earth Radii planets does not substantially differ between the two datasets. With future additions to the M dwarf M-R relation from TESS and instruments like the Habitable Zone Planet Finder, we will be able to characterize these differences in more detail, which will help illuminate the process of planetary formation and evolution around these stars. We release a publicly available Python code called MRExo which uses the nonparametric algorithm introduced by Ning et al. (2018) to fit the M-R relationship. Such a nonparametric fit does not assume an underlying power law fit to the measurements and hence can be used on samples spanning large mass and radii ranges. Therefore by not assuming a functional form, the fit is less biased. MRExo also offers a tool to predict mass from radius posteriors, and vice versa. This functionality can help inform observational strategies for radial velocity campaigns, such as TESS follow-up studies, as well as predict radii with microlensing planet masses.
Mass and radius of planets transiting their host stars are provided by radial velocity and photometric observations. Structural models of solid exoplanet interiors are then constructed by using equations of state for the radial density distribution,
We present high precision, model independent, mass and radius measurements for 16 white dwarfs in detached eclipsing binaries and combine these with previously published data to test the theoretical white dwarf mass-radius relationship. We reach a me
We present the discovery and characterisation of two transiting planets observed by the Transiting Exoplanet Survey Satellite (TESS) orbiting the nearby (d ~ 22 pc), bright (J ~ 9 mag) M3.5 dwarf LTT 3780 (TOI-732). We confirm both planets and their
We report the confirmation of a transiting planet around the bright, inactive M0.5 V star TOI-1235 (TYC 4384-1735-1, V = 11.5 mag), whose transit signal was detected in the photometric time series of Sectors 14, 20, and 21 of the TESS space mission.
In the near future, extremely-large ground-based telescopes may conduct some of the first searches for life beyond the solar system. High-spectral resolution observations of reflected light from nearby exoplanetary atmospheres could be used to search