The RADEX modeling results shown in the ¹²CO J = 6−5 peak temperatures and the ¹³CO/C¹⁸O ratios for three different ¹²CO column densities. The column densities of ¹³CO and C¹⁸O were fixed at the isotopologic abundance ratio of 1/60 and 1/490 of the ¹²CO column density. The line widths of ¹²CO, ¹³CO, and C¹⁸O were fixed at 5, 5, and 4 km s^-1, respectively. The red and blue contours denote the temperature and H₂ number density, respectively, and the color points represent the data in the different regions of the OMC-1 core. Each point represents a peak ¹²CO J = 6−5 temperature and a temperature ratio between ¹³CO J = 8 − 7 and C¹⁸O J = 6−5 from a single pixel with a resolution of 20″. a) The modeling input column density of ¹²CO is 1 × 10¹⁸ cm^-2, and the data are plotted in a ¹²CO column density density of 7.5 × 10¹⁷ − 2.5 × 10¹⁸ cm^-2. b) The modeling input column density of ¹²CO is 5 × 10¹⁸ cm^-2, and the data are plotted in a density range of 2.5 × 10¹⁸ − 7.5 × 10¹⁸ cm^-2. c) The modeling input column density of ¹²CO is 1 × 10¹⁹ cm^-2, and the data are plotted in the density of  ≥7.5 × 10¹⁸ cm^-2. Upper right panel shows the ¹²CO column density map toward Orion BN/KL in contours of 5, 10, 20, 30, and 40 × 10¹⁸ cm^-2. The stars mark the positions of the five Trapezium stars, and the Orion Hot Core (HC) position is also marked.