Coronal Element Comparison Observed by SOHO SUMER in the Quiet Southeast and Northwest Limb Regions at 1.04 R☉ above the Solar Disk

The composition in an isothermal region at 1.04 R☉ above a diffuse, quiet coronal region on the northwest limb is studied and compared with a similar region above the southeast limb analyzed by Warren in 1999. Elemental abundances relative to H in the corona are measured and normalized to the abundance ratios in the photosphere. The enrichment factors of the low first ionization potential elements are comparable above both limbs, but are significantly smaller than the factor of 4 in SUMER spectra obtained 2 years earlier at solar minimum in a diffuse, quiet equatorial region.

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