Table 1: Derived parameters for each of the molecular clouds along the line of sight of LBV 1806-20 and SGR 1806-20, using the 12CO(J=1-0) spectra.
Name W(CO*)a $V_{\rm lsr}$b $A_{\rm V}$ Near distanceb Far distanceb Distanceb
  (K km s-1) (km s-1) (mag) (kpc) (kpc) (kpc)
MC -16 28.4 -14.9 8.6 $\pm$ 1.7 n.a. 24.9 4.5
MC 4 12.7 4.3 3.9 $\pm$ 0.8 0.2 16.6 0.2
MC 13A 32.8 12.7 10.0 $\pm$ 2.0 1.7 15.1 15.1
MC 13B 9.8 16.7 3.0 $\pm$ 0.6 2.2 14.5 4.5
MC 24 18.3 23.6 5.6 $\pm$ 1.1 3.0 13.8 3.0
MC 30 2.6 30.0 0.8 $\pm$ 0.2 3.5 13.2 3.5
MC 38 3.6 38.4 1.1 $\pm$ 0.2 4.2 12.6 4.2
MC 44 5.0 43.5 1.6 $\pm$ 0.3 4.5 12.3 4.5
MC 73 19.8 73.4 6.0 $\pm$ 1.2 5.7 11.0 ...c
MC 87 4.5 87.9 1.4 $\pm$ 0.3 6.1 10.6 ...c
MC 94 1.7 94.2 0.5 $\pm$ 0.1 6.2 10.5 ...c
a W(CO*) is the integrated line area of the cloud. The error on W(CO*) itself is negligeable compared to the 20% uncertainty we assume to take into account the uncertainties in the various conversion factors for $A_{\rm V}$.
b In the text, we use a systematic error of $\pm$10 km s-1 on the velocity of the cloud in order to derive a robust distance range (>2$\sigma$) for each of the molecular clouds.
c We did not attempt to resolve the distance ambiguity for MC 73, MC 87 and MC 94, since they are between MC -16 and MC 13A in either case.

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