6. Colour excess
The colour excess for each line of sight, adopted from different publications, is given in Table 1. All lines of sight show total values of lower than 0.20 mag. The main problem is to separate the contributions of the Galactic foreground from the colour excess within the Magellanic Clouds. For LH 10:3120 (LMC) and HD 5980 (SMC), we adopt values for from previous publications (de Boer et al. 1998; Richter et al. 1998). For HD 269698 and HD 269546, we have calculated the foreground extinction from the H I column densities of the Galactic foreground gas by using the mean gas-to-colour excess relation, as given by Bohlin et al. (1978). The values for are presented in Table 3. Their errors are based on the uncertainty for (as cited in the literature; see Table 1) in addition to the uncertainty for the Galactic foreground reddening, which shows variations in the range of 0.05 mag in direction of the LMC and 0.02 mag toward the SMC (Bessel 1991).
© European Southern Observatory (ESO) 2000
Online publication: July 13, 2000