This is the Hankel transform of the convolution of the beam and the pointing error (or jitter), effectively representing the effect of smearing of the map due to these effects. The first column is ℓ and the second column is the Legendre coefficient in the expansion. The square of the second column is the window function. The window function is shown in Figure 2 of Kusaka et al.
These 100 files contain realizations of the noise in the ABS maps. These realizations are generated using the observations that went into the final maps. In particular, they include pixel-to-pixel correlations and long timescale correlated, or so-called 1/f, noise.