Top-left panel: slit-reconstructed intensity map of NOAA AR 12480 observed by IRIS at Mg II k_2V. Top-middle panel: location of the representative profiles (RPs). Top-right panel: location on the solar disk of the IRIS Mg II h and k database observations and their (color-encoded) exposure time. Bottom panels: from left to right, T, v_los, and electron density (log(n_e)) evaluated at log(τ) = −4.