Spectra of NH₃ (1, 1) and HC₃N (2−1) lines toward the molecular core L1498 obtained at the Effelsberg 100-m radio telescope. The offset (Δα,Δδ) = (0′′,0′′). The histograms show the data averaged over two spectral channels. The fits are shown with solid curves. The vertical tick-marks indicate the positions and the relative strengths of the hyperfine structure components for local thermodynamical equilibrium and optically thin emission. The residual spectra are plotted below each profile. The fitting parameters are presented in Table 2.