Table 2.

Average physical parameters toward different regions of OMC 1

	L[C ii]/LFIR	LCO 2—1/LFIR	L[C ii]/LCO 2–1	LFIR/MGas (L☉=M☉)	$G_0^b$ (Habing field)	τ d,160
OMC1 (full mapa)	3.8(5.4)×10−3	3.6(6.2)×10−6	1200(900)	43(27)	7.5×103	0.03(0.03)
Extended Cloud (R>0.4 pc)	4.7(6.0)×10−3	4.5(7.5)×10−6	1400(900)	35(20)	3.2×103	0.02(0.02)
Dense PDR interface (0.16<R<0.24 pc annulusa)	1.1(0.5)×10−3	6.6(2.2)×10−7	1600(500)	87(24)	3.3×104	0.08(0.05)
Toward H ii around Trapezium (R<0.1 pc)	9.3(3.9)×10−4	5.4(1.8)×10−7	1700(400)	126(18)	3.3×104	0.05(0.02)

Note. — Average values over the different template cloud regions defined in Section 3.2. Numbers in parenthesis represent the standard deviation (1σ) of each sample. L_FIR refers to the 40-500 μm range.

^aThe central Orion BN/KL region (50′×50′) is not included in the computation of the average values due to saturation of the photometric measurements. A low L[C _ii]/L_FIR≃(2-8)×10⁻⁵ luminosity ratio and t_d,160≃1-3 was inferred from Herschel/PACS spectroscopic observations (Goicoechea et al. 2015). The mean L[C ii]/L_{CO 2–1} ratio in this region is ~270.

^bEstimated from I_FIR and Equation 3.