  We have imaged two normal, non-coronal, infrared-bright K giants, Alpha Tau
and Alpha Boo, in the 1.4-mm and 2.8-mm continuum using the Berkeley Illinois
Maryland Association millimeter array. These stars have been used as important
absolute calibrators for several infrared infrared satellites. Our goals are:
(1) to establish whether these stars radiate as simple photospheres or possess
long-wavelength chromospheres; and (2) to make a connection between millimeter
wave and far-infrared absolute flux calibrations. To accomplish these goals we
also present Infrared Space Observatory Long Wavelength Spectrometer
measurements of both these K giants. The far-infrared and millimeter continuum
radiation is produced in the vicinity of the temperature minimum in Alpha Tau
and Alpha Boo. We find that current photospheric models predict fluxes in
reasonable agreement with those observed for wavelengths which sample the upper
photosphere, namely <=125 microns in Alpha Tau and Alpha Boo. We clearly detect
chromospheric radiation from both stars by 2.8mm (by 1.4mm in the case of Alpha
Boo). Only additional observations can determine precisely where beyond 125
microns the purely radiative models fail. Until then, purely radiative models
for these stars can only be used with confidence for calibration purposes below
125 microns.
