Four stellar-diameter measurements by a new technique: amplitude interferometry.

Diameters are reported for four late-type giant stars, a Boo, a Ori, a Tau, and p Peg. The diameters were obtained with a new kind of interferometer designed expressly to operate in the presence of atmospheric fluctuations. The new technique, called amplitude interferometry, is briefly described. The results include measurements of a Ori at several wavelengths. Subject headings: image processing - instruments - late-type stars