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The NSF's Daniel K. Inouye Solar Telescope (DKIST) is the largest solar telescope in the world, with a 4-m off-axis primary mirror and 16-m rotating coudé laboratory within the telescope pier. Due to its off-axis design, the mount size is equivalent to an on-axis 8-m class telescope. Like other large, complex telescopes, DKIST is affected by vibrations related to its size and several important rotating entities (e.g. enclosure, coudé, telescope mount). However, the DKIST must also disperse a solar heat load of 13kW, using a complex thermal design supplemented by several additional vibration sources. The diffraction limit of the telescope makes the optical error budget very tight, with the allotted budget for vibrations jitter set as low as 70 milli-arcsec. This translates to a few hundred nanometers RMS on certain mirrors, with the impact of jitter on on-sky image motion varying relative to the mirror position in the optical path. The DKIST recently celebrated the end of its construction phase in November 2021, enabling the start of operations and allowing science programs to be started. Vibrations data recording and management has become part of the telescope verification during observing, enabling early detection of new frequency peaks and amplitude increases in known frequencies. Previous vibrations surveys at DKIST were conducted by William McBride who has proposed and presented an allocations budget per location in 2018, implemented and measured various paths analyses, and linked those results to the AO system. As the transition to operations progressed and operations continues, several vibration sources have been activated. Comparisons of current vibration levels to the previous budget is ongoing in order to identify where solutions to improve performance and facilitate AO correction are required. We were notified of two strong frequencies (40 Hz and 80 Hz) contributing significantly to image motion, identified within the High Order Adaptive Optics (HOAO) performance report. Presented herein is the process used to identify the source of that vibration by building a knowledge base of the telescope’s vibration signature, and using data identification of the problematic peaks to find the vibration hardware’s source. An improved design was then engineered, tested and implemented. Finally, by comparing results to prior HOAO measurements, the improvement in performance can be quantified.
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