SUMER Limb Images

North Coronal Hole observed by SUMER 10.Aug.96

Fe XII

Mg X

O V

N V

Cont.

On 10.Aug.96, SUMER scanned the Solar north pole in order to observe the coronal hole boundary. This was part of a campaign called Whole Sun Month and only the first of several similar observations. - The SUMER studies were initiated by D. Hassler.

The scan lasted 16 hours (00:03 - 16:11 UT) and covered 300 arcsec (north-south) and 1444 arcsec (east-west). The raster step size was 1.5 arcsec, 960 detector images were taken with an exposure time of 60 seconds each. The commanded lines were

Iron XII at 1242.01 Å (corona)
Magnesium X at 624.943 Å (corona)
Oxygen V at 629.729 Å (transition region)
Nitrogen V at 1238.82 Å (transition region)

The continuum was subtracted from the resp. lines, which was only partially successful in the case of the (relatively weak) Fe XII line. - Intensities are not on the same scale.

IED, 05.Sep.97