(a) Cloud-model calculation of the Mg ii h line profile with the values of free parameters: V_LOS = −40 km s⁻¹, V_turb = 40 km s⁻¹, τ₀ = 0.5, and α = 0.6. The synthesized line profile well reproduces the averaged profile from the observation. The calculated line profile I (Δλ) is shown in the orange solid line, the background intensity I₀(Δλ) in the green-dotted line, the two terms in the radiative transfer equation I₀exp[−τ(Δλ)] and S{1 − exp[−τ(Δλ)]} in the blue-colored dash-dotted line and red-colored dot-dot-dot-dashed line, respectively. The intensity is normalized by the background peak intensity, I₀(Δλ = 0). (b) Comparison of the calculated [orange thinner solid line, which is the same as in the panel (a)] and the observed (black thicker solid line) profile of the Mg ii h line. The background intensity, I₀(Δλ), is also shown by the green-dotted line. The vertical-dashed line shows the position of the rest wavelength corresponding to Δλ = 0. The solid vertical line indicates the wavelength position of the emission from the moving cloud. Its line-of-sight velocity is V_LOS = 40 km s⁻¹. Note that the bisector method generally leads to smaller shifts compared to the cloud-model fitting (The typical blueshift corresponded the velocity of 10.1 ±  2.6 km s⁻¹ by the bisector method in the observation). (Color online)