Inversion results of the physical quantities at the location of the fibrils in our sample and their background lanes; top panels: mean profile of the temperature (left), line-of-sight velocity (middle) and microturbulence (right). The fibrillar profiles are plotted with red and the background profiles are plotted with black curves. The range of [μ − σ, μ + σ] is shown with the bands with the same colour as the mean profiles in each of the panels on top, where μ is the mean value and σ is the standard deviation of the physical parameters for all the pixels along the fibrils and their backgrounds. The horizontal dotted line marks the depth log(τ_500 nm) = −4.31. Bottom panels: joint probability distributions of the physical parameters in the fibrillar pixels and their background lane at log(τ_500 nm) = −4.31. The Pearson correlation coefficient r and the y = x line is shown in each panel of the bottom row.