LVG predictions at T = 10 K towards L1544 (left) and L1498 (right). In each panel, the grey scale shows the predicted intensity of the 110024.590 MHz component of the C¹⁵N(1–0) hyperfine multiplet. The boxes (full line) delineate the solutions for the C¹⁵N (cyan) and the ¹³CN lines (white). The dashed box shows the C¹⁵N solutions when the C¹⁵N column density is multiplied by factors of 7.5 and 7 for L1544 and L1498 respectively.