Back to Volume
Paper: Spitzer Observations of Star Formation in Four H II Region Environments
Volume: 432, New Horizons in Astronomy: Frank N. Bash Symposium 2009
Page: 259
Authors: Snider-Finkelstein, K. D.
Abstract: We present an analysis of star formation in four galactic H II region environments using Spitzer IRAC and MIPS 24 μm observations. In each study young stellar objects (YSOs) are identified, and the spatial distribution of these objects is measured. In order to clarify the effect ionization fronts have on the star formation in these regions, we calculate the distances of the YSOs from the ionization fronts identified in the region, as well as distances to the nearby massive OB stars. The distributions show that there is a correlation between the locations where YSOs are forming and the locations of ionization fronts created by the massive stars. A total of 624 YSOs were detected in the four regions. The candidate YSOs were classified into protostellar evolutionary classes based on their colors and spectral energy distributions (SEDs). An online YSO SED fitter from Robitaille et al. (2007) was used to analyze the physical properties of the YSOs. These properties along with the distribution of the YSOs are used to calculate the amount of triggered star formation occurring in each region. Calculated triggered star formation rates range from 14 – 58% of the total star formation rate, demonstrating that triggering due to H II region expansion of new protostars is occurring in multiple H II regions, and may be an important mode of star formation in these types of environments.
Back to Volume