A Comparison of the Composition of Planets in Single- and Multi-Planet Systems Orbiting M dwarfs

• DOI: 10.48550/arxiv.2307.13034
• Publication Date: 2023-01-01
• Authors: Romy Rodríguez Ma...; David V. Martin; B. Scott Gaudi; Joseph G. Schulze; Anusha Pai Asnodkar; Kiersten M. Boley; Sarah Ballard
• Keywords: Star (game theory)

We investigate and compare the composition of M-dwarf planets in systems with only one known planet (``singles") to those residing multi-planet (``multis") fundamental properties their host stars. restrict our analysis directly measured masses radii, which comprise a total 70 planets: 30 singles 40 multis 19 systems. bulk densities for full sample, includes ranging size from $0.52 R_{\oplus}$ $12.8R_\oplus$, find that single have significantly lower on average than multis, we cannot attribute selection biases. normalized by an Earth model $R_{p} < 6R_{\oplus}$, are also denser 99\% confidence. calculate core/water mass fractions (CMF/WMF) low-mass ($M_p <10 M_{\oplus}$), likely rocky (with $R_p <1.6 R_{\oplus}$) CMFs singles. [Fe/H] metallicity rotation period all versus stars such measurements literature hosts more metal-poor hosting planet. Moreover, star decreases increasing multiplicity. In contrast, modest difference period. The significant differences planetary point different physical processes governing formation single- M dwarfs.