Measured Lyα(Lyα) × Lyβ(Lyβ) correlation function in four ranges of μ. In order to see the asymmetry of this correlation function, is multiplied by the sign of r_∥ which is positive if the Lyα absorber is farther than the Lyβ absorber, and negative in the opposite configuration. The model for this correlation function (red solid line) is fitted on Lyα(Lyα) × Lyα(Lyα), Lyα(Lyα) × Lyα(Lyβ) and Lyα(Lyα) × Lyβ(Lyβ).