Table 2
Column density of H2NS and N2H+ in our source sample and their corresponding abundances and NS:N2H+ ratios.
| Source | # | Offsets |  |
 |
 |
N(NS)/N(N2H+) | N(NS)/NH | [N2H+](‡) | |
|---|---|---|---|---|---|---|---|---|---|
| ′′ | ′′ | cm−2 | cm−2 | cm−2 | × 10−11 | × 10−11 | |||
| L1521E | 1 | –30 | –10 | 22.37(8) | >12.8 | >13.5 | |||
| 2 | +10 | –10 | 22.23(9) | >12.9 | >23.4 | ||||
| 3 | –10 | –10 | 22.33(7) | 12.8(2)(a) | 11.67(7) |  |
 |
1.0(b) | |
| 4 | –10 | –30 | 22.33(8) | >12.6 | >9.33 | ||||
| L1521B | 1 | 50 | –20 | 22.24(6) | 12.25(10) |  |
|||
| 2 | 30 | –20 | 22.23(7) | 12.35(10) |  |
||||
| 3 | 10 | –20 | 22.16(7) | 12.15(10) |  |
||||
| 4 | 0 | 0 | 22.10(7) | 12.3(1)–13.2(1) | <12.3(c) | >1 |  |
<7.9(c) | |
| 5 | 20 | 0 | 22.20(7) | 12.3(1) |  |
||||
| 6 | 40 | 0 | 22.24(7) | 12.3(1) |  |
||||
| 7 | 60 | 0 | 22.23(6) | 12.1(1) |  |
||||
| L1498 | 1 | 0 | 0 | 22.26(17) | 12.3(2)(a) |  |
|||
| 2 | –10 | –20 | 22.20(20) | 12.2(1)(a) |  |
||||
| 3 | +20 | –10 | 22.26(17) | 12.15(20)(a,d) |  |
||||
| 4 | +10 | +20 | 22.25(16) | 12.7(2) | 12.86(2)(e) |  |
 |
20.0(c) | |
| 5 | –20 | +10 | 22.17(20) | 12.0(1) |  |
||||
| 6 | +20 | –40 | 22.28(17) | 12.1(1) |  |
||||
| 7 | -40 | +20 | 22.14(20) | 12.0(1) |  |
||||
| 9 | +60 | –30 | 22.24(18) | 12.6(2)(a,d) |  |
||||
| 10 | +80 | –40 | 22.14(25) | 12.4(1)(a) |  |
||||
| L1544 | 1 | 0 | 0 | 22.82(1)(f) | 12.0(1) | 13.6(1) | 0.023(6) |  |
33(d) |
| 2 | 20 | 20 | 22.64(2)(f) | 11.9(1) | 13.5(1) | 0.028(6) |  |
33(d) | |
| 3 | 20 | –20 | 22.68(1)(f) | 12.1(1) | 13.5(1) | 0.040(9) |  |
33(d) | |
Notes. Numbers in brackets are 1σ uncertainties in units of the last digit. Column (2) gives the spectrum number as shown in Figs. 2 and 3. (†) Column density (log10) measured in a 35′′, 21′′ and 26′′ -beams for H2, NS and N2H + respectively (see Appendix A and Table A.1). (‡) Abundance relative to H nuclei in units of 10−11. (a) Column density of NS determined using both J = 5∕2–3∕2 and J = 7∕2–5∕2 manifolds. (b)Constant N2H + abundance taken from Tafalla & Santiago (2004). (c)Based on the upper limit on N(N2H+) taken from Hirota et al. (2004). (d)Temperature held fixed at 10 K. (e)N2H+ abundance and column density from Daniel et al. (2007) (see Sect. 4.1). (f) Based on the constant N2H + /H2 abundance of 6.5 × 10−10 from Bizzocchi et al. (2013).
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