Chemical network results for Drop CO abundance with the Test 1 source profile from Jørgensen et al. (2002) for four cases (Table 2). Case d is the same as in the top row center panel of Fig. 6.

Chemical network results for Drop CO abundance with the decreased-temperature (Test 4) source profile for four cases (Table 2). Case d is the same as in the bottom row center panel of Fig. 6.

Chemical network results for Drop CO abundance with the decreased-temperature source profile (Test 4) for case d with upper-limit (left), thermal (center) and lower-limit (right) o/p ratio.

DCO⁺ Cycle 0 observations compared with the radial profile of the constant and drop CO abundance models, showing the effect of the factor used to decrease the temperature, for case d. A factor of 1.5 with drop CO abundance provides the best approximation to the observed radial profile.

Comparison of the observations and radiative transfer modeling of the chemical network results. The black line shows the DCO⁺ observations integrated over the southern clump, with the gray solid and dashed lines showing the 1σ and 4σ levels, respectively. Models are referred to by test, abundance profile (Constant “C” or Drop “D”) and case. Color lines show tests 1 (blue), 2 (green), 3 (orange) and 4 (purple) for the top left panel, and cases a (blue), b (green), d (orange) and f (purple) for the other four panels.

As in Fig. A.5 but for C¹⁸O. Gray solid and dashed lines show the 1σ and 3σ levels respectively. Note that constant CO abundance over-predicts the amount of C¹⁸O emission.