Distribution of the Extinction and Star Formation in NGC 1569
  We investigate spatial the distribution of the intrinsic extinction in the starburst dwarf galaxy NGC1569 creating an extinction map of the whole galaxy derived from the Halpha/Hbeta emission line ratio. We differentiate the extinction in the HII regions from the extinction of the diffuse gas. The intrinsic extinction shows considerable variations over the plane of the galaxy, from negligible extinction up to highest values of A(V)=0.8mag. The extinction map shows small scale clumpy structures possibly due to a clumpy dust distribution. We also identify in this map a shell structure, for which we establish a causal relation with the expanding gas structure produced by the stellar winds coming from the Super Star Clusters (SSC) in the center of the galaxy. The comparison of the spatial profiles of the extinction, dust and gaseous emissions crossing the border of the shell shows a layered structure; the peak of this Halpha distribution lying closest to the SSC A, followed outwards by the peak of the extinction and at a still larger distances by the bulk of the atomic gas. We suggest that the extinction shell has been produced by the SSCs and that it can be explained by the accumulation of dust at the border of this ionized gas structure. 
M. Relano (1), U. Lisenfeld (1), J.M. Vilchez (2), E. Battaner (1)   ((1) Universidad de Granada, (2) Instituto de Astrofisi...