Signal amplitude as a function of the uv distance, namely the baseline length. We extracted the signal amplitude at three different spatial locations, coinciding with the NE clump (blue), the SW clump (red), and the C clump (gray). We fit each dataset with a Gaussian model plus a constant. In the image plane these best-fit functions correspond to a Gaussian with FWHM ∼ 2″ and a PSF component. An additional constant, corresponding to another PSF component, is needed to fit the measurements.