Poster Abstracts

Name/Affiliation:  Leslie Hebb (Hobart and William Smith Colleges)

Title:  Precise fundamental properties of a surprisingly hot, low metallicity, 0.2 Msun M dwarf 

Abstract:
We present the analysis of a newly discovered late M dwarf (0.2 Msun) in a 14-day eclipsing binary with a higher mass G-dwarf primary star. By performing stellar characterization on the primary star spectra and a detailed eclipsing binary analysis using the radial velocity curve combined with the optical and infrared light curves, we derive an accurate mass, radius, temperature and metallicity for both the primary and secondary components. The result of our analysis shows the primary star to be a 10 Gyr old, -0.4 metallicity, 0.925 Msun star evolving off the zero age main sequence. The mass and radius of the M dwarf secondary are consistent with stellar evolution models of the same age and metallicity for a 0.2 Msun star, but the temperature is significantly hotter than expected. We find a surprisingly hot temperature of 3800 K for this very low mass star.