Position offset derived in the uv plane along the disk major axis as a function of the velocity channel in L1527 for panel). In each panel the blue and red points with the error bars show the observations, the solid line shows the result of a power-law fit. The dashed line in the right panel shows the result of a fit with a Keplerian law with . Only filled points are considered in the power-law and Keplerian fits. The dotted lines show the velocity fit from Aso et al. (2017).