Counting rates for one-minute periods of the SN-SNT between 19:00 and 22:00 UT for the SOL2011-03-07 event. The black solid line represents the counting rate of the N1 channel, while the red dashed curve shows the counting rate of the L1 channel. To compare both counting rates, the counting rate of the L1 channel is multiplied by a factor of 3.138. The definition of the N and L channels are given in the text. The vertical bar represents the statistical error of each point. The black dashed curve corresponds to the best-fitting curve to the N1 count by the third-order polynomial function |$y\ = {\rm{\ }}212.11{x^3} - 13287{x^2} + 276410x - 1823533$|⁠, where y represents the counting rate for one minute, while x corresponds to the time in units of hours (UT). The vertical green lines delimit the times of the two significant increases. (Color online)