Solar H i Lyman α full disk profile obtained with the SUMER / SOHO spectrometer

نویسنده

  • K. Wilhelm
چکیده

An uncalibrated solar hydrogen Lyman α profile was obtained with the use of the spectrometer on SOHO. The collection of the light scattered by the telescope permitted to average the profile over the full solar disk. The profile taken at the L1 Sun-Earth Lagrangian position is free of the central geocoronal absorption. Then, taking advantage of the absolute flux measured by the SOLSTICE/UARS spectrometer, an absolute line profile intensity is derived, and is compared with previous observations at minimum solar activity.

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تاریخ انتشار 1998