1ST RESULTS FROM THE GODDARD HIGH-RESOLUTION SPECTROGRAPH - THE CHROMOSPHERE OF ALPHA-TAURI

The K5 III star-alpha-Tau was observed with the Goddard High Resolution Spectrograph on 1990 November 27 as part of the Science Assessment Program for the Hubble Space Telescope. The observations include spectra in both the Large and Small Science Apertures in modes G270M at 2345 angstrom and echelle B at 2325 angstrom. The spectra show intersystem and permitted chromospheric emission lines of C II], Si II], Fe II, Fe I, Ni II, and Co II. Resolved profiles of the C II] lines indicate a complex chromospheric turbulent velocity distribution with mean value of almost-equal-to 24 km s-1, while their observed wavelengths indicate a 4 km s-1 downflow of the C II] plasma. Twenty-five new emission lines have been found in the 2320-2370 angstrom region, 17 of which have been identified with the aid of Skylab data obtained above the solar limb, including four lines from Co II (UV 8) and an Fe I (UV 12) line. The Co II lines confirm the earlier identification of the 2330 angstrom line as a Co II (UV 8) fluorescent feature, and the Fe I line represents a third product of the Mg II kappa-Fe I pumping which produces the Fe I (UV 44) lines near 2823 and 2844 angstrom. The Skylab spectrum shows different line strengths due to the higher density and lower optical depths of the solar chromosphere above the visible limb.