Laura Lopez (MIT)

Under Pressure: Assessing the Role of Stellar Feedback in HII Regions

Observations show that star formation is an inefficient and slow process. This result can be attributed to the injection of energy and momentum by stars that prevents free-fall collapse of molecular clouds. The dominant mechanism of this stellar feedback is debated theoretically: possible sources of pressure include the classical warm HII gas, the hot gas shock-heated by supernovae and stellar winds, the direct radiation from stars, and the dust-processed radiation field trapped inside an HII shell. In this talk, I will discuss how one can measure the pressures associated with these feedback processes using multiwavelength data (radio, infrared, optical, and X-ray), and I will present the results from applying these techniques to a sample of HII regions in the Large and Small Magellanic Cloud. I will consider the implications regarding the dynamics and the regulation of star formation in these regions.