SUMER study: Reference spectrum above an active region

Remarks: The commanded wavelength was only partially covered by the spectral window. - A reference spectrum was performed afterwards, pointing the slit to the middle of the field of view. - The active region can be identified in a Yohkoh image taken 16 h earlier.


Spectral window


Average detector image, average profile.


H I Ly b 1025.4 (20 000 K)


Line intensity.


IED, 11.Nov.98