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In the first panel there is the fractional difference for LIVETIME: as you can see, there are differences up to a few percent (~5%). The second panel shows a zoom of a region: we can clearly see a small growing trend inside each and every run, and some occasional larger "flares". As you can see in the third panel, those flares seem symmetrically distributed around the zero line, with a upward fluctuation followed by a downward fluctuation of the same amount. But, two fluctuations can combine giving a third fluctuation which is the opposite of the algebraic sum of the former two. This also means that this should NOT usually be a problem for analysis using 30s FT2 files, or in general spanning more than few seconds in general, because those problems will cancel out.
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