Multiwavelength study of RCW 108 as a massive star

G. A. ROMERO, R. H. BARBÁ, AND E.M. ARNAL

Cariló, Bs. As., Argentina

Workshop; Massive Stars: Fundamental Parameters and Circumstellar Interactions; 2006

Fac. Cs. Astronómicas y Geofísicas-UNLP

Optical narrow-band imaging (obtained at CTIO) and infrared data (retrieved from archives) of the galactic HII region RCW 108 reveal a beauty structure of mixed gas and dust, which is a good example of a developed massive star forming region. The spatial distribution of the dust and the ionization structure in the nebula are studied using MSX experiment (mid-IR), 2MASS (near-IR) and Halpha, [SII], [OIII] (optical) images. In this work, we describe the morphology of the distribution of the photoionized and shock-excited gas caused by the energetic action of the multiple O-type star systems (HD 150135 and HD 150136) in the core of the open cluster NGC 6193, and other undiscovered sources. Also,we find four additional distinctive photodisociated regions, which are also correlated with CO emission clumps. Finally, we identify several candidates for young stellar objects (YSOs) based on the analysis of the properties of sources extracted from the 2MASS and MSX Point Sources Catalogues. These results lead to the fact that star forming activity is a widespread phenomenon in the RCW 108 nebula beyond the known object RCW 108-IR.