SIMULTANEOUS OBSERVATIONS OF SOLAR PLAGE WITH THE SOLAR EXTREME-ULTRAVIOLET ROCKET TELESCOPE AND SPECTROGRAPH (SERTS), THE VLA, AND THE KITT PEAK MAGNETOGRAPH

We obtained simultaneous images of solar plage on 1991 May 7 with NASA/Goddard Space Flight Center's Solar Extreme Ultraviolet Rocket Telescope and Spectrograph (SERTS), the Very Large Array (VLA),4 and the NASA/National Solar Observatory5 spectromagnetograph at the NSO/Kitt Peak Vacuum Telescope. Using intensity ratios of Fe XVI to Fe XV emission lines, we find that the coronal plasma temperature is (2.3-2.9) x 10(6) K throughout the region. The column emission measure ranges from 2.5 x 10(27) to 1.3 x 10(28) cm-5. The calculated structure and intensity of the 20 cm wavelength thermal bremsstrahlung emission from the hot plasma observed by SERTS is quite similar to the observed structure and intensity of the 20 cm microwave emission observed by the VLA. Using the Meyer (1991, 1992) revised coronal iron abundance, we find no evidence either for cool absorbing plasma or for contributions from thermal gyroemission. Using the observed microwave polarization and the SERTS plasma parameters, we calculate a map of the coronal longitudinal magnetic field. The resulting values, approximately 30-60 G, are comparable to extrapolated values of the potential field at heights of 5000 and 10,000 km.