Subtract background emission

Background emission

Sometimes it is necessary to subtract a background spectrum from measured emission spectra, e.g. if the sample is highly scattering or there is a strong Raman signal that must be removed. In an actual experiment, the background spectrum must be acquired using the exact same excitation wavelength and slit bandwidths as the original spectrum. 

Subtract background fluorescence in a|e

In a|e, background emission signals are put in a data structure separate from absorption and emission spectra and loaded into the 'Emission background' data listbox.

1. If not already activated, activate the 'Background subtraction' toggle button in the toolbar. This will activate the 'Emission background' data listbox.

2. Background signals can be loaded into the data listbox via the '+' button located below the listbox. In this example the background is simply some synthetically fabricated spectrum for illustrative purposes only.

3. When loaded, and selected in the listbox, the background spectrum is plotted in full-drawn black and is not shown in the legend of the figure. Press the Subtract button located above the 'Emission background' data listbox.

4. This will open a selection dialog box. All spectra selected in the left listbox will have the background spectrum selected in the right listbox subtracted. Press OK.

The new spectrum is in this example highlighted in thick.