I rebuilt our COMSOL model in order to see if I could find any errors in it and to clean out unnessesary features and parameters. The model returned the same results as before, and I did not find anything wrong with it while rebuilding it. Running an Eigenfrequency solver gives the first real mode as a sheer mode, indicating that a normal meshing may be insufficient, but finer meshes result in an out of memory during LU factorization error despite having just rebooted the computer used and having several gigs of unused RAM. I have also submitted a ticket to COMSOL support asking for assistance with the relative residual error, but the initial response I recieved was unhelpful. Hopefully I get a more helpful response soon. I have started working through a LiveLink for Matlab tutorial (http://www.rz.uni-karlsruhe.de/~hf118/tutorial_comsol_matlab_livelink.pdf) I found from a third party and reading example Matlab code, since I am not familiar with Matlab. I will continue reading through this documentation for the next day or so, then hopefully will recieve useful help from the COMSOL support team. If so, I can start working on using Matlab Livelink to parameterize our model and vary the radius of the back face of the mirror to replicate Steve Penn's results. Otherwise, I may try doing so with the increase of relative tolerance which caused the stationary solution to converge last week.