Solid points are the residual radial velocity measurements of the primary star phase-folded with exactly one-half the orbital period of the binary. Phase 0.0 is arbitrary and does not correspond to the T₀. The solid line is the best fitting model sine curve with a and an amplitude of 1.5 km s^-1. The sinusoidal variation that is detected is consistent with the presence of two star spots on opposite hemispheres of the primary star.