Rigaut, FrancoisMinowa, YosukeAkiyama, MasayukiOno, YoshitoKorkiakoski, VisaHerrald, NicholasGausachs, GastonClergeon, ChristopheWang, Shiang-Yud'Orgeville, CelineDavies, J. A.Koyama, YuseiIwata, IkuruKodama, TadayukiMotohara, KentaroHayano, YutakaTanaka, IchiClose, L.Schreiber, L.Schmidt, D.2020-02-102020-02-10June 10-15978-151061959-3http://hdl.handle.net/1885/201603We report on the conceptual design study done for the Ground Layer Adaptive Optics system of the ULTIMATE-Subaru project. This is an ambitious instrument project, providing GLAO correction in a square field of view of 14 arcmin on a side, aiming to deliver improved seeing at the near infrared wavelength. Its client instruments are an imager and multi-IFU spectrograph at Cassegrain and a Multi-Object spectrograph at Nasmyth. In this paper, we introduce the ULTIMATE-Subaru project overview and its science case and report the results of the GLAO performance prediction based on the numerical simulation and conceptual design of the wavefront sensor systemThe development of ULTIMATE-Subaru is partly supported by the Japan Society for the Promotion of Science (Grant-in-Aid for Research #17H06129).application/pdfen-AUCopyright 2018 Society of Photo-Optical Instrumentation Engineers201810.1117/12.23140852019-11-25