Same as Fig. 4, except that instead of integrated intensities the signal-to-noise ratio is shown. The noise is computed by, where N is the number of channels over which integration was performed, Av is the channel separation in km s⁻¹, and σ is the median rms noise level as shown in Table 2 in Belloche et al. (2019). Values of CH₃OCH₃, CH₃OCHO, and CH₃CHO are scaled down by a factor of 2, those of C₂H₅CN and C₂H₃CN by a factor 3, HC¹³CCN by a factor 5, HNCO by a factor 4. The contour steps are 3, 9, 18, 36, 72, 144, 288, and 576.