I've been attempting to create a repository of all the self-heating wavefront maps measured with the HWS and I reviewed each of the 8 test masses. Some of the measurements are much cleaner than others.

In particular, I discovered that the ETMY HWS is somehow not functioning correctly as it shows a negative thermal lens associated with the interferometer powering up which would imply negative absorption. This is clearly non-physical as it probably violates several laws of thermodynamics. My suspicion is that the mode-matching on the source beam needs to be improved (difficult with the multi-mode fibers we need to use to get the required intensity). We will investigate further. 

https://ldas-jobs.ligo.caltech.edu/~aidan.brooks/