MUltiplexed Survey Telescope (MUST) Science White Paper I: Overview of Large-Scale Structure Cosmology in the Era of Stage-V Spectroscopic Surveys

Cheng Zhao; Song Huang; Mengfan He; Paulo Montero-Camacho; Yu Liu; Pablo Renard; Yunyi Tang; Aurelien Verdier; Wenshuo Xu; Xiaorui Yang; Jiaxi Yu; Yao Zhang; Siyi Zhao; Xingchen Zhou; Shengyu He; Jean-Paul Kneib; Jiayi Li; Zhuoyang Li; Wen-Ting Wang; Zhong-Zhi Xianyu; Yidian Zhang; Rafaela Gsponer; Xiao-Dong Li; Antoine Rocher; Siwei Zou; Ting Tan; Zhiqi Huang; Zhuoxiao Wang; Pei Li; Maxime Rombach; Chenxing Dong; Daniel Forero-Sanchez; Yuanhang Ning; Huanyuan Shan; Tao Wang; Yin Li; Zhongxu Zhai; Yuting Wang; Gong-Bo Zhao; Yong Shi; Shude Mao; Lei Huang; Liquan Guo; Zheng Cai

arXiv · 2411.07970

MUltiplexed Survey Telescope (MUST) Science White Paper I: Overview of Large-Scale Structure Cosmology in the Era of Stage-V Spectroscopic Surveys

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Abstract

The MUltiplexed Survey Telescope (MUST) is a 6.5-meter telescope under development. Dedicated to highly-multiplexed, wide-field spectroscopic surveys, MUST observes over 20,000 targets simultaneously using 6.2-mm pitch positioning robots within a ~5 deg$^2$ field of view. MUST aims to conduct the first Stage-V spectroscopic survey in the 2030s, mapping the 3D Universe with over 100 million galaxies and quasars, spanning from the nearby Universe to a redshift of z ~ 5.5, corresponding to approximately 1 billion years after the Big Bang. To cover this extensive redshift range, we present an initial conceptual target selection algorithm for different types of galaxies, ranging from local bright galaxies and luminous red galaxies to emission-line galaxies, and high-redshift (2 < z < 5.5) Lyman-break galaxies. Using Fisher forecasts, we demonstrate that MUST can address fundamental questions in cosmology, including the nature of dark energy, tests of gravity theories, and investigations into primordial physics. This is the first paper in the series of science white papers for MUST, with subsequent developments focusing on additional scientific cases such as galaxy and quasar evolution, Milky Way physics, and dynamic phenomena in the time-domain Universe.

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Cheng Zhao, Song Huang, Mengfan He, Paulo Montero-Camacho, Yu Liu, Pablo Renard, Yunyi Tang, Aurelien Verdier, Wenshuo Xu, Xiaorui Yang, Jiaxi Yu, Yao Zhang, Siyi Zhao, Xingchen Zhou, Shengyu He, Jean-Paul Kneib, Jiayi Li, Zhuoyang Li, Wen-Ting Wang, Zhong-Zhi Xianyu, Yidian Zhang, Rafaela Gsponer, Xiao-Dong Li, Antoine Rocher, Siwei Zou, Ting Tan, Zhiqi Huang, Zhuoxiao Wang, Pei Li, Maxime Rombach, Chenxing Dong, Daniel Forero-Sanchez, Yuanhang Ning, Huanyuan Shan, Tao Wang, Yin Li, Zhongxu Zhai, Yuting Wang, Gong-Bo Zhao, Yong Shi, Shude Mao, Lei Huang, Liquan Guo, Zheng Cai. 2024-11-12. MUltiplexed Survey Telescope (MUST) Science White Paper I: Overview of Large-Scale Structure Cosmology in the Era of Stage-V Spectroscopic Surveys. https://arxiv.org/abs/2411.07970

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