Likelihood profiles assuming a flat ρ₀ density profile for different exposure times ΔT, starting at either T₀ (left) or T₀ + 1 d (right). ΔL is defined as the difference between the likelihood and that corresponding to the E_CR value which maximises it unconditionally (black dashed line). In all panels, the grey dashed line represents the 95% limit, and the obtained likelihoods are interpolated employing a cubic spline.