Automatically determined time series (solid line) for three of the cuts taken to analyse loop 2 in Event 1 fitted with a damped cosine function (thick dashed line). Top: s = 16 Mm. Center: s = 21 Mm. Bottom: s = 26 Mm. The errors on the fitting parameters are the errors given by the fitting technique. The error bars on each plot show the typical size of the error in the loop position. The displacement amplitude has been normalised by the loop length. The vertical dashed line indicates the start of the oscillation at t₀ = 05:35:59 UT.