Radio Interferometric Image Restoration

Given that an interferometer measures the data in the Fourier domain, the modulation transfer function will 

FIGURE 4 The Fourier plane sampling pattern (top) and the resulant point-spread functions (bottom) for an observation with the Very large Array (near Socorro, New Mexico). The first sampling pattern corresponds to a very brief observation (a so-called snapshot). The second corresponds to a 6-hr observation, where the earth s rotation has been used to improve the sampling pattern in the Fourier plane. 

The point-spread functions in radio interferometry differ from those in many imaging applications. First, the 

As with optical astronomy, bias of the maximum entropy solution can be problematic in blank regions of the sky. The bias tends to create an artificial plateau of emis- 

Although this is most noticeable in low-sensitivity images, the bias exists (but in a more subtle form) even when the sensitivity is very good. Deconvolving point sources is also problematic with maximum entropy algorithms, particularly when the point source lies on top of a plateau of emission. 

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