Results From The Pti'S Studies Of The Spectral Angular Diameters Of Mira Variables

A dedicated program of measuring angular sizes of Mira variables using the Palomar Testbed Interferometer has resulted in more than 13,000 measurements of over 60 stars. With visibility data in five channels across the K band, atmospheric extension and sources of opacity are evident in the dataset. Using multiple-epoch narrow-band data, phase lags between wavelength-dependent angular size cycles indicate spatial extent of molecular atmospheres. A spectral angular diameter classification system is developed, based on the recurring shapes of the spectral traces seen in the dataset, which correlates to spectral type. A period-radius relationship is explored, and a refinement on the estimation of angular sizes is made.