THE MM-TO-SUBMM CONTINUUM SPECTRA OF W-3(OH) AND K-3-50A

We present a model for the integrated flux density of W 3 (OH) and K3- 50A allowing these sources to be used as reliable secondary calibrator s between 80 and 800 GHz. Using new narrow-band continuum measurements between 86-245 GHz with the 30m telescope and reasonable assumptions about the source sizes, we construct continuum spectra from the mm-to- submm range which are in very good agreement with previously published data. With the fit parameters given in this paper, observers at any s ingle-dish telescope will be able to calculate the expected flux densi ties of the two sources at any given aperture and frequency.