GALACTIC H-ALPHA EMISSION AND THE COSMIC MICROWAVE BACKGROUND

We present observations of Galactic H alpha emission along two declina tion bands where the South Pole cosmic microwave background experiment reports temperature fluctuations. The high spectral resolution of our Fabry-Perot system allows us to separate the Galactic signal from the much larger local sources of H alpha emission, such as the Earth's ge ocorona. For the two bands (at delta = -62 degrees and -63 degrees), w e find a total mean emission of similar to 1 R with variations of simi lar to 0.3 R. The variations are within the estimated uncertainty of o ur total intensity determinations. For an ionized gas at T similar to 10(4) K, this corresponds to a maximum free-free brightness temperatur e of less than 10 mu K at 30 GHz (K-band). Thus, unless there is a hot gas component with T similar to 10(6) K, OUT results imply that there is essentially no free-free contamination of the SP91 (Schuster et al . 1993) and SP94 (Gunderson et al. 1995) data sets.