Table of Contents
Last updated: 29 February, 2016.
HIFI spectra produced by the Level 2 pipeline often show baselines that are offset, sloped, curved, and/or rippled. In many cases, these are leftovers from instrumental instabilities inherent to heterodyne techniques, and not completely removed by reference or sky subtraction in the HIFI pipeline. Depending on the science application, you may want to flatten the baseline, either by subtraction, or, in the presence of real continuum emission, by division. This can be done in HIPE at the Level 2 stage, using the tasks described in the next sections.