Spectral irradiance calibration in the infrared. X. A self-consistent radiometric all-sky network of absolutely calibrated stellar spectra

We start from our six absolutely calibrated continuous stellar spectra from 1.2 to 35 mu m for K0, K1.5, K3, K5, and M0 giants. These were constructed as far as possible from actual observed spectral fragments taken from the ground, the Kuiper Airborne Observatory, and the IRAS Low Resolution Spectr ometer, and all have a common calibration pedigree. From these we spawn 422 calibrated "spectral templates" for stars with spectral types in the range s G9.5-K3.5 III and K4.5-M0.5 III. We normalize each template by photometry for the individual stars using published and/or newly secured near- and mi d-infrared photometry obtained through fully characterized, absolutely cali brated, combinations of filter passband, detector radiance response, and me an terrestrial atmospheric transmission. These templates continue our ongoi ng effort to provide an all-sky network of absolutely calibrated, spectrall y continuous, stellar standards for general infrared usage, all with a comm on, traceable calibration heritage. The wavelength coverage is ideal for ca libration of many existing and proposed ground-based, airborne, and satelli te sensors, particularly low- to moderate-resolution spectrometers. We anal yze the statistics of probable uncertainties, in the normalization of these templates to actual photometry, that quantify the confidence with which we can assert that these templates truly represent the individual stars. Each calibrated template provides an angular diameter for that star. These radi ometric angular diameters compare very favorably with those directly observ ed across the range from 1.6 to 21 mas.