Daniel K. Inouye Solar Telescope (DKIST) Construction Update

July 15, 2014, from David Williams (UKSP DC)

The Daniel K. Inouye Solar Telescope (DKIST) project (formerly known as the Advanced Technology Solar Telescope, or ATST) began site construction in 2013. The 4m DKIST will be the world’s largest solar telescope, and once operational with its full set of five first light instruments in 2019, DKIST will provide high resolution observations of solar magnetic fields on disk and in the faint corona. Work at the DKIST site, located at the University of Hawaii Haleakala Observatory, has progressed significantly; the DKIST building now reaches to nearly half of its designed height. Steel support beams for the Telescope Mount Assembly have been installed (see http://dkist.nso.edu/node/1923), and tests are being conducted on the Coude rotation assembly (see http://dkist.nso.edu/node/1919) at the manufacturer. If everything continues as planned, the foundations for the Support and Operations building and the lower enclosure will be complete by the end of the summer, allowing the enclosure assembly to begin early in the fall of 2014. Additional images of construction activities and progress can be viewed on the NSO web site (http://dkist.nso.edu/).

The figuring and polishing of the M1 blank has begun in the University of Arizona College of Optical Sciences (COS) lab. This blank was recently finished by Schott and is of exceptional quality. Test work by the COS team on the figuring procedure using the DKIST test blank went well, and work on the M1 is expected to proceed smoothly, with an estimated completion date of March 2015. Work on the other DKIST optics including the polarization package and the wavefront correction systems are being done now in a parallel effort.

The five DKIST first-light instruments are in a variety of phases in their developments; this plan is meant to facilitate an orderly commissioning sequence at the telescope. The Visible Broadband Imager (VBI) has completed the manufacturing phase, is undergoing alignment and testing at the NSO headquarters in Boulder CO, and is expected to be the first instrument installed at DKIST. The Cryogenic Near-Infrared Spectropolarimeter (Cryo-NIRSP) has passed its Critical Design Review (CDR) and will begin fabrication in August 2014. The Visible Tunable-Filter (VTF) is expecting to complete fabrication by 2018. The Diffraction-Limited Near-Infrared Spectropolarimeter (DL-NIRSP) will undergo its CDR later this fall, with the Visible Spectropolarimeter (VISP) CDR following in early 2015.

The DKIST project is a collaborative effort of 22 institutions, and the international solar physics community provides input to the project through the DKIST Science Working Group (SWG), which meets next at the end of October 2014. The SWG is working on a Critical Science Plan detailing the initial science experiments to be run at the DKIST. Members of the solar physics community who are interested in DKIST science should contact Mark Rast, the chair of the DKIST Science Working Group (Mark.Rast@lasp.colorado.edu) or the DKIST Project Director (rimmele@nso.edu).

Matthew Penn