deletions | additions       diff --git a/Concepts.tex b/Concepts.tex  index 89a3f3e..d31f300 100644  --- a/Concepts.tex  +++ b/Concepts.tex 
...
counts” originating from the detectors dark counts, out of focus molecules  and sample scattering and/or auto-fluorescence\cite{Gopich_2008}.   These two processes can be   observed in the distribution of timestamps timestamps'  delays (i.e. the waiting times between two subsequent timestamps) as illustrated in Figure~\ref{fig:bgdist}.  The “tail” of the distribution (a line in semi-log scale) corresponds   to exponentially-distributed delays, indicating that those counts are generated by a