The scatter of the M dwarf mass-radius relationship
M dwarfs are prime targets in the hunt for habitable worlds around other stars. This is due to their abundance as well as their small radii and low masses and tempera- tures, which facilitate the detection of temperate, rocky planets in orbit around them. However, the fundamental properties of M dwa...
| Autores: | , , , |
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| Formato: | artículo |
| Fecha de publicación: | 2018 |
| País: | España |
| Recursos: | Universitat Politècnica de Catalunya (UPC) |
| Repositorio: | UPCommons. Portal del coneixement obert de la UPC |
| Idioma: | inglés |
| OAI Identifier: | oai:upcommons.upc.edu:2117/127463 |
| Acesso em linha: | https://hdl.handle.net/2117/127463 https://dx.doi.org/10.1093/MNRAS/STY2345 |
| Access Level: | acceso abierto |
| Palavra-chave: | Double stars Binaries - eclipsing Stars - fundamental parameters Stars - late-type Estels binaris Àrees temàtiques de la UPC::Física::Astronomia i astrofísica |
| Resumo: | M dwarfs are prime targets in the hunt for habitable worlds around other stars. This is due to their abundance as well as their small radii and low masses and tempera- tures, which facilitate the detection of temperate, rocky planets in orbit around them. However, the fundamental properties of M dwarfs are difficult to constrain, often lim- iting our ability to characterise the planets they host. Here we test several theoretical relationships for M dwarfs by measuring 23 high precision, model-independent masses and radii for M dwarfs in binaries with white dwarfs. We find a large scatter in the radii of these low-mass stars, with 25 per cent having radii consistent with theoret- ical models while the rest are up to 12 per cent over-inflated. This scatter is seen in both partially- and fully-convective M dwarfs. No clear trend is seen between the over-inflation and age or metallicity, but there are indications that the radii of slowly rotating M dwarfs are more consistent with predictions, albeit with a similar amount of scatter in the measurements compared to more rapidly rotating M dwarfs. The sample of M dwarfs in close binaries with white dwarfs appears indistinguishable from other M dwarf samples, implying that common envelope evolution has a negligible impact on their structure. We conclude that theoretical and empirical mass-radius relationships lack the precision and accuracy required to measure the fundamental parameters of M dwarfs well enough to determine the internal structure and bulk composition of the planets they host. |
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