Visiting astronomer, Kitt Peak National Observatory.

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NOAO is operated by the Association of Universities for Research in Astronomy, Inc., under cooperative agreement with the National Science Foundation.

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...factor

As far as coherence is concerned, this paper follows the terminology and notations of Goodman (1985). However the term ``fringe visibility'' will sometimes be used as a synonym for coherence factor.

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...distribution

Rigorously speaking, this statement holds only as long as the chromaticism 211#211 of the injection efficiency, which appears implicitly in F via the coefficient 212#212, does not vary significantly between the observations of the object and the reference. It might be possible that this effect becomes apparent with very large telescopes, because of differential refraction, if the two sources are observed at different zenithal distances (Coudé du Foresto 1994).

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