Properties of ISM in two star-forming regions

Abstract

The Hi-GAL provides an opportunity to make a complete and unbiased view of the continuum emission in the Galactic plane in five bands: 70, 160, 250, 350, and 500 μm. Our research focuses on two of star-forming regions. The first one is the molecular cloud, which includes G45.12+0.13 and G45.07+0.13 UCHII regions. Using the Modified blackbody fitting on Herschel images obtained in four bands: 160, 250, 350, and 500 μm, we determined the distribution of N(H2) hydrogen column density and Td dust temperature. The maps of N(H2) and Td show that UCHII regions clearly stand out against the general background of the molecular cloud with a relatively low density (from 1.0 x 1023 to 3.0 x 1023 cm-2) and significantly higher temperature (up to 100 K), what is fully consistent with the basic concept of UCHII regions about the presence of a hot, high mass stellar source and stellar wind, which leads to the blowing out of matter. The second one is the elongated star-forming region, which includes five stellar subgroups around IRAS 05184+3635, 05177+3636, 05168+3634, 05162+3639 and 05156+3643 sources. Here, on the contrary, the N(H2) is noticeably higher (from 1.0 x 1023 to 5.0 x 1023 cm-2) than in the surrounding molecular cloud and the Td does not exceed 25 K.