Suzaku and Chandra study of diffuse X-ray emission from the massive star-forming region RCW 38.

This article focuses on the analysis of diffuse X-ray emission in the young massive star-forming region RCW 38, located approximately 1.7 kpc from Earth. Using observations from the Suzaku and Chandra satellites, the study distinguishes between thermal and non-thermal origins of the diffuse emission by modeling spectra from inner and outer regions around the cluster center. Results indicate that while both thermal plasma models (with temperatures around 0.9 keV and several keV) and non-thermal power-law models can fit the inner region’s emission, the outer region’s emission is better explained by a two-temperature thermal plasma model. The study concludes that thermal emission, likely arising from shocks caused by massive stellar winds interacting with surrounding molecular clouds, dominates at least in the outer region, though non-thermal components may also be present near the cluster center. The findings highlight the importance of interstellar absorption and local environment in shaping the X-ray emission properties and suggest that future high-resolution spectral observations could clarify the elemental abundances and origins of the diffuse emission.