Acknowledgements

AD is supported by a Macquarie University Research Excellence Scholarship (MQRES) and a Sigma Xi Grants-in-Aid of Research (GIAR). AD thanks the anonymous referee for helpful suggestion and comments that improved the paper, Helge Todt for providing the PoWR models for expanding atmospheres and valuable comments, Jorge García-Rojas and Miriam Peña for providing the Magellan Telescope data and helpful comments, Ralf Jacob for sharing results from radiation-hydrodynamics simulations and valuable suggestions, Christophe Morisset for illuminating discussions and corrections, Quentin A. Parker for providing the 2010 ANU 2.3-m data, David J. Frew for helping with the ANU observing proposal, Kyle DePew for carrying out the 2010 ANU observing run, and Roger Wesson for sharing the program EQUIB (originally written by I. D. Howarth and S. Adams at UCL). The computations in this paper were run on the NCI National Facility in Canberra, Australia, which is supported by the Australian Commonwealth Government, the swinSTAR supercomputer at Swinburne University of Technology, and the Odyssey cluster supported by the FAS Division of Science, Research Computing Group at Harvard University.