Hertzsprung-Russell diagram for the sample of rotational and ellipsoidal binaries. From left to right, the points are color coded according to the logarithm of its orbital period, P_VR, the mass of the primary star, and the adopted spectroscopic metallicity [M/H]. Black points correspond to stars with unreliable extinction determination (mostly stars with T_eff ≤ 3700 K; see Sect. 3.1) and therefore potentially unreliable stellar parameters, while those with a thick black edge are the rotational candidates. The grey lines correspond to constant radii of 10, 30, 60, 90, 120, 150, and 180 R_⊙. In the right panel, the evolutionary tracks for a 1 M_⊙ (green curve) and a 6 M_⊙ (green dashed curve) star, having Z = 0.004 ([M/H]∼ − 0.6), from the grid computed by Lagarde et al. (2012), based on the STAREVOL (Siess et al. 2000) code, are included.