Here is some information about how Skyline calculates background:
https://skyline.ms/wiki/home/software/Skyline/page.view?name=tip_peak_calc

The column "Total Background" in the document grid shows the sum of the background values from all of the Transitions.
If your molecule has only one transition then Background and Total Background will be the same value.
-- Nick

Thank you for your response.


Is that a way to obtain S/N on skyline?

Not really. Signal is normally the background subtracted peak height at the apex and the noise is normally the standard deviation of the signal that the peak is superimposed. We don't currently have a true S/N calculation in Skyline. The closest would be to calculate the CV from replicate injections and take the reciprocal. So instead of the stdev/mean take the mean/stdev. So a CV of 20% is essentially a S/N of 5. We have discussed adding specific S/N calculations for individual runs but it would have to be done on a per transition level and you would get very different results depending on where you decided to calculate the noise of the background from -- basically it is complicated. Because it is complicated we have not prioritized it yet.

Cheers,
Mike