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The National Science Foundation’s Daniel K. Inouye Solar Telescope (DKIST) is the largest solar telescope in the world, utilizing a 4m off-axis primary mirror sending light to a ∼16m wide rotating multi-instrument coudé laboratory supported by a highly complex active and adaptive optics system, delivering a diffraction limited beam. The resulting mount size, long optical pathways, various moving components, and complex thermal design leaves DKIST with a very tight optical error budget that is susceptible to vibration-related degradation. Prior to and throughout the early stages of DKIST operations, there has been an ongoing survey to identify and address vibration sources affecting the optical path of the telescope. Using data from our High Order Adaptive Optics (HOAO) and Power Spectral Density (PSD) data taken from accelerometers placed throughout the site, we have been able to record and track noteworthy frequencies as they appear throughout various phases of operations. Efforts within the last year have allowed for improvements in this vibration survey with increased monitoring via expansion in both the frequency and scale of data collection. This has enabled us to distinguish and categorize several vibration sources that encompass both high impact individual frequencies and overall noise, in order to prioritize solutions for those with the highest impact on image motion. Components of the DKIST facility thermal system and end consumer internal thermal processes, requisitely located throughout the telescope mount and coud´e in order to remove waste heat from temperature sensitive areas, often prove to be the sources of such vibration. Presented herein are recent examples of sources with significant impact, including the details on how we tracked and identified them, and the solutions that were implemented in order to reduce jitter. As DKIST continues operations, future vibration mitigation efforts will be supported by additional data from other instruments in order to identify opportunities for optimization and further isolate localized vibration within our optics systems.
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