Driving Turbulence and Triggering Star Formation by Ionizing Radiation
arXiv:0901.2113 · doi:10.1088/0004-637X/694/1/L26
Abstract
We present high resolution simulations on the impact of ionizing radiation of massive O-stars on the surrounding turbulent interstellar medium (ISM). The simulations are performed with the newly developed software iVINE which combines ionization with smoothed particle hydrodynamics (SPH) and gravitational forces. We show that radiation from hot stars penetrates the ISM, efficiently heats cold low density gas and amplifies over-densities seeded by the initial turbulence. The formation of observed pillar-like structures in star forming regions (e.g. in M16) can be explained by this scenario. At the tip of the pillars gravitational collapse can be induced, eventually leading to the formation of low mass stars. Detailed analysis of the evolution of the turbulent spectra shows that UV-radiation of O-stars indeed provides an excellent mechanism to sustain and even drive turbulence in the parental molecular cloud.
5 pages, 2 figures, accepted by ApJ Letters
References in corpus (8)
- The Global Evolution of Giant Molecular Clouds. I: Model Formulation and Quasi-Equilibrium Behavior
- TRAPHIC - Radiative Transfer for Smoothed Particle Hydrodynamics Simulations
- iVINE - Ionization in the parallel tree/SPH code VINE: First results on the observed age-spread around O-stars
- Ionisation-induced star formation II: External irradiation of a turbulent molecular cloud
- VINE -- A numerical code for simulating astrophysical systems using particles I: Description of the physics and the numerical methods
- Sequential star formation in a cometary globule (BRC37) of IC1396
- VINE -- A numerical code for simulating astrophysical systems using particles II: Implementation and performance characteristics
- Spitzer Observations of the HII Region NGC 2467: An Analysis of Triggered Star Formation