A new detached M dwarf eclipsing binary

We describe a newly discovered detached M dwarf eclipsing binary system. This system was first observed by the TrES network during a long-term photometry campaign of 54 nights. Analysis of the folded light curve indicates two very similar components orbiting each other with a period of 1.12079 ± 0.00001 days. Spectroscopic observations with the Hobby-Eberly Telescope show the system to consist of two M3e dwarfs in a near-circular orbit. Double-line radial velocity amplitudes, combined with the orbital inclination derived from light-curve fitting, yield M_total = 0.983 ± 0.007 M _⊙, with component masses of M₁ = 0.493 ± 0.003 M_⊙ and M₂ = 0.489 ± 0.003 M_⊙. The light-curve fit yields component radii of R₁, = 0.453 ± 0.060 R_⊙ and R₂ = 0.452 ± 0.050 R _⊙. Although a precise parallax is lacking, broadband VJHK colors and spectral typing suggest component absolute magnitudes of M_v(1) = 11.18 ± 0.30 and M_v(2) = 11.28 ± 0.30.