Table 1: Calculated wavelengths, Einstein coefficients (A_ij) and line strengths (S_ij) for the low-lying transitions of CH₂ (ignoring hyperfine-structure in the ortho transitions). The estimated error corresponding to the last significant figure of the calculated wavelengths is given in parenthesis. The Einstein coefficients and line strengths calculated here are half those given by Sears et al. (1984). The detected lines towards Sgr B2 are shown in bold.
Transition Wavelength A_ij S_ij

( $\mu$ m) (s^-1)

1₁₁-0₀₀ J=0-1 127.31450 (6) 0.0163 0.989

1 $_{{\bf 11}}$ -0 $_{{\bf00}}$ ${\vec J} \bf =1$ -1 127.85823 (4) 0.0163 3.02

1 $_{{\bf 11}}$ -0 $_{{\bf00}}$ ${\vec J}\bf =2$ -1 127.64614 (5) 0.0163 4.99

2₁₁-2₀₂ J=1-1 153.102312 (6) 0.0105 3.31

2₁₁-2₀₂ J=1-2 154.302721 (7) 0.00351 1.14

2₁₁-2₀₂ J=2-1 152.621311 (6) 0.00217 1.14

2₁₁-2₀₂ J=2-2 153.814187 (6) 0.00962 5.15

2₁₁-2₀₂ J=2-3 152.992296 (6) 0.00216 1.14

2₁₁-2₀₂ J=3-2 154.178941 (6) 0.00151 1.14

2₁₁-2₀₂ J=3-3 153.352914 (7) 0.0125 9.25

3₁₃-2₀₂ J=2-1 93.5838 (1) 0.0298 3.60

3₁₃-2₀₂ J=2-2 94.0309 (1) 0.00559 0.685

3₁₃-2₀₂ J=2-3 93.7231 (2) 0.000170 0.0205

3₁₃-2₀₂ J=3-2 93.7025 (2) 0.0317 5.37

3₁₃-2₀₂ J=3-3 93.3967 (2) 0.00392 0.657

3₁₃-2₀₂ J=4-3 93.6621 (2) 0.0356 7.75

1₁₀-1₀₁ J=0-1 156.43947 (1) 0.0133 0.500

1₁₀-1₀₁ J=1-0 155.66632 (1) 0.00462 0.513

1₁₀-1₀₁ J=1-1 157.56539 (1) 0.00318 0.366

1₁₀-1₀₁ J=1-2 156.76825 (1) 0.00548 0.622

1₁₀-1₀₁ J=2-1 157.12503 (2) 0.00323 0.615

1₁₀-1₀₁ J=2-2 156.33233 (1) 0.0101 1.88

2₁₂-1₀₁ J=1-0 107.2947 (2) 0.0134 0.487

2₁₂-1₀₁ J=1-1 108.1935 (2) 0.0103 0.385

2₁₂-1₀₁ J=1-2 107.8170 (2) 0.000731 0.0270

2₁₂-1₀₁ J=2-1 107.8573 (2) 0.0184 1.13

2₁₂-1₀₁ J=2-2 107.4832 (2) 0.00603 0.367

2 $_{{\bf 12}}$ -1 $_{{\bf01}}$ ${\vec J}\bf =3$ -2 107.7203 (2) 0.0244 2.10

**Table 1:** Calculated wavelengths, Einstein coefficients (A_ij) and line strengths (S_ij) for the low-lying transitions of CH₂ (ignoring hyperfine-structure in the ortho transitions). The estimated error corresponding to the last significant figure of the calculated wavelengths is given in parenthesis. The Einstein coefficients and line strengths calculated here are half those given by Sears et al. (1984). The detected lines towards Sgr B2 are shown in bold.
Transition	Wavelength	A_ij	S_ij
	( $\mu$ m)	(s^-1)
1₁₁-0₀₀ J=0-1	127.31450 (6)	0.0163	0.989
1 $_{{\bf 11}}$ -0 $_{{\bf00}}$ ${\vec J} \bf =1$ -1	127.85823 (4)	0.0163	3.02
1 $_{{\bf 11}}$ -0 $_{{\bf00}}$ ${\vec J}\bf =2$ -1	127.64614 (5)	0.0163	4.99
2₁₁-2₀₂ J=1-1	153.102312 (6)	0.0105	3.31
2₁₁-2₀₂ J=1-2	154.302721 (7)	0.00351	1.14
2₁₁-2₀₂ J=2-1	152.621311 (6)	0.00217	1.14
2₁₁-2₀₂ J=2-2	153.814187 (6)	0.00962	5.15
2₁₁-2₀₂ J=2-3	152.992296 (6)	0.00216	1.14
2₁₁-2₀₂ J=3-2	154.178941 (6)	0.00151	1.14
2₁₁-2₀₂ J=3-3	153.352914 (7)	0.0125	9.25
3₁₃-2₀₂ J=2-1	93.5838 (1)	0.0298	3.60
3₁₃-2₀₂ J=2-2	94.0309 (1)	0.00559	0.685
3₁₃-2₀₂ J=2-3	93.7231 (2)	0.000170	0.0205
3₁₃-2₀₂ J=3-2	93.7025 (2)	0.0317	5.37
3₁₃-2₀₂ J=3-3	93.3967 (2)	0.00392	0.657
3₁₃-2₀₂ J=4-3	93.6621 (2)	0.0356	7.75
1₁₀-1₀₁ J=0-1	156.43947 (1)	0.0133	0.500
1₁₀-1₀₁ J=1-0	155.66632 (1)	0.00462	0.513
1₁₀-1₀₁ J=1-1	157.56539 (1)	0.00318	0.366
1₁₀-1₀₁ J=1-2	156.76825 (1)	0.00548	0.622
1₁₀-1₀₁ J=2-1	157.12503 (2)	0.00323	0.615
1₁₀-1₀₁ J=2-2	156.33233 (1)	0.0101	1.88
2₁₂-1₀₁ J=1-0	107.2947 (2)	0.0134	0.487
2₁₂-1₀₁ J=1-1	108.1935 (2)	0.0103	0.385
2₁₂-1₀₁ J=1-2	107.8170 (2)	0.000731	0.0270
2₁₂-1₀₁ J=2-1	107.8573 (2)	0.0184	1.13
2₁₂-1₀₁ J=2-2	107.4832 (2)	0.00603	0.367
2 $_{{\bf 12}}$ -1 $_{{\bf01}}$ ${\vec J}\bf =3$ -2	107.7203 (2)	0.0244	2.10

Source LaTeX | All tables | In the text

	1 Introduction
	2 CH₂ rotational spectrum
	3 Observations and data reduction
	4 Sgr B2 results
	5 Abundances
	6 CH₂ in other sources
	7 Discussion
	8 Summary
	Appendix A: Observations used
	References