I temporarily installed a modal damping filter on the longitudinal degree of freedom of ETMX. The filter has 32 poles, so it is split between two modules, 'md_part1' and 'md_part2'. I plan to measure ringdown times of the test mass tomorrow using the green cavity signal. This is part of an effort to see what are the fastest possible ringdown times of the test mass with top mass damping. After the test I will remove the filters. Normally a modal damping filter wouldn't need this many poles, but I decided to include the pitch dynamics in the estimator to get a more faithful reproduction of the 1st longitudinal mode frequency for this test.