Table D.1

Synthetic fitting of the detected S-bearing species toward NGC 1333-IRAS4A for a range of excitation temperatures between 150 and 300 K, a FWHM of 1.8″, and a source size of 2″. Directly across from a specific minor isotopolog under “Derived N of isotopologs” follows the column density of the main isotopolog upon the assumption of the standard isotopic ratio. In bold in the same column is the average column density of the main isotopolog based on all the available minor isotopologs (only if the minor isotopolog is optically thin and including the uncertainties).

Species	Transition	Frequency (GHz)	Eup (K)	Aij (s−1)	Beam size (″)	N (cm−2)	Derived N of isotopologs (cm−2)	τ
H2S	22,0-21,1	216.710	84	4.9×10−5	6.1	op. thick		0.4-1.2
H2 33S	22,0,1-21,1,2	215.494	84	2.4×10−5	6.8	3×1014	N(H2S)=(3.8-8.0)×1016	0.0003-0.0007
	22,0,1-21,1,1	215.497	84	2.4×10−5				0.0003-0.0007
	22,0,4-21,1,3	215.501	84	6.9×10−6				0.0004-0.0008
	22,0,4-21,1,4	215.503	84	4.1×10−5				0.0020-0.0080
	22,0,2-21,1,3	215.504	84	1.7×10−5				0.0005-0.0010
	22,0,2-21,1,2	215.505	84	1.9×10−5				0.0005-0.0010
	22,0,2-21,1,1	215.508	84	1.2×10−5				0.0003-0.0007
	22,0,3-21,1,3	215.512	84	2.8×10−5				0.0010-0.0020
	22,0,3-21,1,2	215.513	84	1.1×10−5				0.0005-0.0010
	22,0,3-21,1,4	215.513	84	9.1×10−6				0.0004-0.0008
H2 34S	22,0-21,1	214.377	84	4.7×10−5	6.8	6.3×1014	N(H2S)=(1.4-2.9)×1016	0.01-0.03
OCS, υ = 0	19-18	231.061	111	3.6×10−5	6.2	op. thick		0.5-1.1
OC33S	18-17	216.147	99	2.9×10−5	6.8	1.0×1014	N(OCS)=(1.3-1.9)×1016	0.003-0.007
O13CS	19-18	230.318	110	3.5×10−5	6.3	1.4×1014	N(OCS)=(0.1-1.3)×1016	0.005-0.010
18OCS	19-18	216.753	104	3.0×10−5	6.1	3.8×1013	N(OCS)=(2.3-3.0)×1016	0.001-0.002
OCS, υ2 = 1−	19-18	231.342	860	3.5×10−5	5.6	(0.4-1.2)×1015		0.001-0.002
OCS, υ2 = 1+	19-18	231.584	860	3.5×10−5	5.6			0.001-0.004