Radial velocities of AVab (solid circle), two emission peaks of He I 5876 (asterisk), redshifted absorption components of Na I D1 and D2 (dot and open circle), the redshifted absorption component of Fe II lines (open square), and absorption lines in the infrared region of the M-type giant (triangle). The dotted lines exhibit the radial velocities of the hot component and the M-type giant in the circular orbit, while the broken lines indicate those in the elliptical orbit.