Free Access

Fig. 2

image

Voronoi diagram of E(BV) based on the extended nebular Hα/Hβ ratio, binned to a signal-to-noise ratio of 200 per polygon. The color coding is linear between E(BV) = 0 mag (white) and E(BV) = 1.8 mag (black). The extinction is highest close to MWC 137 and along the rim of the nebula, tracing the dust. It decreases toward the outskirts of the cluster. The white spots are stars and MWC 137 is saturated. This diagram serves as illustration. For absolute extinction values, individual spectra were examined (Sect. 3.2).

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.