Extinction and massive stellar population in Andromeda galaxy

P Nedialkov
2015 Bulgarian Chemical Communications   unpublished
We probed to derive a new information on the massive star population and the extinction in the disc of Andormeda galaxy from a ground based UBV stellar photometry. Classical dereddening procedure was applied to evaluate both the extinction of starlight caused by the dust and the intrinsic properties (luminosity, color) of stars themselves. Thus, we were able draw conclusions about the spatial distribution of the dust, and-with the use of isocrones-to estimate the age of each successfully
more » ... ned star. The last parameter allowed us to perform a search for sites of coherent star fomation on different time and size scales. We paid a special attention to the spiral arm S4 where we confirm that evidences exist in support to the density wave theory. Some hidden star formation may be detectable with the available catalog data along the lanes of highest concentration of dust and gas.