Modeling of magnetized star forming cores and gravitational lenses

点击翻译按钮获取中文摘要

The dominant component of this research will model magnetic field geometries and bipolar outflows in star-forming molecular cloud cores and filaments. We will develop a new multi-objective method to model submillimetre polarization maps by building a parametrized model of a magnetized core, simulating the polarization map, and simultaneously fitting to maps of intensity, polarization angles, and polarization fraction. We will apply these models to polarization maps of cores and filaments from the JCMT archive (re-reduced by Matthews et al. 2009, ApJS, 182, 143), and extended to include a new type of non-parametric model, which will characterize magnetic fields in complicated and/or turbulent regions. In addition, we also plan to modify existing software to model CO emission to model bipolar outflows. By specifying a simple geometric model of bipolar outflows, we will be able to build the first global models of star-forming regions that constrain outflow geometries and their orientations with respect to the core's magnetic field. We will apply our method to new JCMT data from the Gould's Belt Survey as it becomes available. The anticipated outcome of this research will include: 1) The best available characterization of magnetic fields in well studied star-forming regions; 2) The first global models of fields and outflows, which will constrain the direction of outflows relative to core magnetic fields; 3) More complete understanding of mathematical degeneracy in polarization models; and 4) Improved understanding of the roles of turbulent vs. orderly magnetic fields in star-forming regions. A secondary component of this research will capitalize on an exciting new method developed by my group to model strong gravitational lens systems. Our method is much more efficient than existing techniques for large images, especially in the presence of significant blurring by a (possibly spatially varying) point spread function. We will apply our method to create the best available models of lens systems in the SLACS catalogue of strong lenses. We will also address a new project from this research, which will use image positions and time delays from multiple lens systems to generate new constraints on cosmological models.