Dr. Nikhil Mukund

Gravitational-wave observatories like Advanced LIGO, which have detected hundreds of black hole mergers, must continually improve their sensing and control strategies to probe ever-fainter cosmic signals. Achieving sustained optimal sensitivity requires balancing stable operation with periodic subsystem upgrades. However, complications arise from optomechanical cross-couplings, environmental non-stationarities, and nonlinearities associated with controlling multiple suspended optical cavities. This talk will discuss some of these instrumentation challenges and how the techniques we developed at the GEO600 GW detector have helped mitigate such effects. These include strategies to reduce angle-to-length disturbances, performing end-to-end adaptive detector calibration, compensating wavefront distortions at high laser powers, and deploying novel deep reinforcement learning techniques to automate the detector alignment. This talk will also cover the recent efforts at MIT in distilling and automating multiple decision-making strategies into optical experiments to tackle commonly occurring issues such as laser beam alignment, power stabilization, polarization control, etc. Drawing on experiences from these experiments, I will discuss how we can incorporate the insights to strengthen ongoing efforts to build and commission the LIGO-India detector.­­