@inproceedings{4bf9fdaacdec4af4b22976a2c06bd2b9,
title = "Subaru Laser Guide Star System Upgrade and On-sky Characterization",
abstract = "The Subaru laser guide star system has been upgraded by implementing the TOPTICA/MPBC guide-star laser and a new mirror-based laser relay system. The upgrade is to replace the aged laser and its transfer system and provide the improved performance for stable science operation. The increased laser return photon can also bring a new capability of generating multiple laser guide stars (LGSs) by splitting the laser beam. The new laser guide star system was installed on the Subaru telescope in December 2021 and commissioning observations were conducted in 2022. The LGSAO mode with the new laser guide star system has been offered for science open use program since 2023. The new laser guide star system provides more stable LGS than the previous system with respect to the laser power and pointing. The LGS spot size is ∼1.0 arcsec in FWHM under median seeing condition. The LGS photon return is more than 10 times brighter than the previous system. By utilizing the increased brightness, further upgrade of the Laser Launching Telescope (LLT) is being implemented to generate the asterism of four LGSs with the diameter variable between 10 and 40 arcsec for the new Laser Tomography Adaptive Optics (LTAO) system.",
keywords = "adaptive optics, laser guide star, laser tomography",
author = "Yosuke Minowa and Yoshito Ono and Yoshiyuki Doi and Yoko Tanaka and Takamasa Bando and Hiroshige Yoshida and Koki Terao and Hirofumi Okita and Matthew Wung and Lucio Ramos and Hajime Ogane and Akimasa Ojika and Masayuki Akiyama",
note = "Publisher Copyright: {\textcopyright} 2024 SPIE.; Adaptive Optics Systems IX 2024 ; Conference date: 16-06-2024 Through 22-06-2024",
year = "2024",
doi = "10.1117/12.3018789",
language = "English",
series = "Proceedings of SPIE - The International Society for Optical Engineering",
publisher = "SPIE",
editor = "Jackson, {Kathryn J.} and Dirk Schmidt and Elise Vernet",
booktitle = "Adaptive Optics Systems IX",
address = "United States",
}