Table 4.

Column Densities and Abundances of NH₂CHO in Molecular Clouds

Source	Ntot(cm−2)	Trot(K)	N(H2) (cm−2)	f(NH2CHO/H2)
Orion-KL	4.7 (1.7)×1013	168	1×1024,a	5×10−11
W51M	9.1 (2.2)×1013	130	1×1024,a	1×10−10
G34.3	1.2 (0.4)×1013	70	5×1023,a	4×10−11
NGC 7538	4.8 (1.5)×1012	177	1×1023,a	5×10−11
M17 SW	2.6 (0.9)×1012	70b	2×1023,c	1×10−11
W3(OH)	3.3 (0.8)×1012	124	1×1023,a	3×10−11
DR21(OH)	1.1 (0.5)×1012	70b	1×1023,a	1×10−11
SgrB2(N)	1.7×1014,d	26	3×1024,d	5×10−11
	4.0×1014,e	134	3×1024,e	1.3×10−10
SgrB2(OH)	7.2 (0.3)×1013,f	13f	1×1024,g	7×10−11
G24.78h	1.4×1013	169	4×1023	3×10−11
G75.78h	2.5×1012	77	1×1023	2×10−11
NGC 6334 IRS1h	3.2×1013	166	2×1023	1×10−10
W33 Ah	1.3×1013	45	2×1023	6×10−11
Comet Hale-Bopp				1–2×10−12,i

^aApponi and Ziurys, 1997.

^bAssumed rotational temperature.

^cStutzki et al., 1988.

^dHalfen et al., 2011, cold component.

^eHalfen et al., 2011, hot component.

^fCummins et al., 1986.

^gSutton et al., 1991.

^hBased on rotational diagrams of Bisschop et al. (2007), assuming a uniform beam-filling factor.

ⁱDerived from the fractional abundance of formamide relative to H₂O, from Bockelee-Morvan et al. (2000). See text.