Solar Limb in Mg X, N V and C I, observed by SUMER 27./28.Apr.96

Study of polar plumes over south coronal hole: Two horizontal scans in alternating directions, each consisting of 200 raster steps (45 seconds exposure time), were taken at the same location (E-W-extension 608 arcsec, N-S-extension 300 arcsec) in three different wavelengths simultaneously.

The first pair (blue) shows the Solar limb in the emission light of Magnesium X at 609.794 Å (corona, temperature approx. 1 000 000 K). The brightest pixel corresponds to approx. 57 counts/line/arcsec²/s (continuum added).

The second pair (green) shows the Solar limb in the emission light of Nitrogen V at 1242.80 Å (transition region, temperature approx. 150 000 K). The brightest pixel corresponds to approx. 163 counts/line/arcsec²/s.

The third pair (red) shows the Solar limb in the emission light of Carbon I at 1253.47 Å (chromosphere, temperature approx. 10 000 K). The brightest pixel corresponds to approx. 9 counts/line/arcsec²/s.

Mg X

N V

C I