红外尘泡 N109 中的恒星形成 postprint

Abstract: Infrared (IR) bubbles associated with HII regions are ideal targets for studying triggered star formation. We present a multi-wavelength (from IR to centimetre wavelengths), comprehensive analysis on the impact of the IR bubble N109, one of the largest bubbles in our Galaxy, on its surroundings and star formation therein. Fifty-six dense clumps are found associated with the bubble and mainly located in the north and west. They all most likely form new stars eventually, five of which most likely form high-mass stars and others of which form low-mass stars. In these two regions there are also five associated compact HII regions, indicative of a new generation of high-mass star formation. In addition, a signature of the compression acting on the surroundings by the expansion of the bubble/HII region is observed in the north and west of N109. These results collectively indicate that N109 is impacting its surroundings due to the expansion of the associated driving HII region. This expansion compresses the surroundings, collecting material to provide physical environments for next generation of star formation, which provides a necessary condition for triggered star formation. We therefore suggest that N109 would be a potential site of triggered star formation.