Left panel: integrated intensity map of the C¹⁸O (1–0) line of Orion B. The green dot denotes the position of the central pixel of the 3 × 3 spectra in the right panel. Right panel: representative spectra are shown with results from the step-by-step decomposing procedure described in Section 3.1.1. Black solid line: original spectrum at each pixel. Blue solid line: smoothed profile with the initial smoothing parameters (Step 1). Red vertical line: initial guesses of velocity component found in Step 1. Green solid line: decomposed Gaussian profiles determined in Step 3 with modified initial guesses from Step 2. Red thick solid line: the profiles combined by decomposed Gaussian components. Red and blue horizontal dotted lines: 3σ levels of original and smoothed profiles, respectively.