M. Ball

I have been modeling cross-coupling between PUM pitch motion and DARM with different decoupling filters (LHO alog 51111) and wanted to investigate the effects of different scalar pitch to length (A2L) decoupling filters.

Figure 1 shows this coupling for a few different A2L gain values with a consistent beam pitch offset. We then wanted to look at how this behaved when the A2L gain is zero/off, as is currently in use (Figure 2). We then asked how this coupling looked for the different spot positions we have been using recently and how those compare to a centered beam (Figure 3).