Figure 1. μSR time spectra and the corresponding Fourier transforms.

The spectra for Ba_0.65Rb_0.35Fe₂As₂ are obtained above (45 K) and below (5 K) T_c (after field cooling the sample from above T_c): (a,c) p=0 GPa and (b,d) p=2.25 GPa. Error bars are the s.e.m. in about 10⁶ events. The error of each bin count n is given by the s.d. of n. The errors of each bin in A(t) are then calculated by s.e. propagation. The solid lines in a and b represent fits to the data by means of equation (3). The solid lines in c and d are the Fourier transforms of the fitted time spectra. The dashed and solid arrows indicate the first moments for the signals of the pressure cell and the sample, respectively.