Final calibrated 10 GHz image before primary beam correction. The size is the same as in Figure 2. The red circle indicates the point where the primary beam sensitivity is 20% of its peak. The gray scale shows the flux density from  −1.5σ to 6σ, where σ = 0.41 μJy beam⁻¹ is the median rms within the primary beam FWHP. The corresponding brightness temperature rms value is σ = 1.25 mK. The image is matched in resolution and depth for a spectral index of −0.7 with the 3 GHz image.