High-frequency water megamasers as precision probes of black holes, galaxies and cosmology: A case for a next-generation sub-mm/mm interferometer
New York University Abu Dhabi（阿布扎比纽约大学）；ASTRON, Netherlands Institute for Radio Astronomy（荷兰射电天文研究所）；Black Hole Initiative, Harvard University（哈佛大学黑洞倡议项目）；European Southern Observatory (ESO)（欧洲南方天文台）；University of Geneva（日内瓦大学）；National Sun Yat-Sen University（国立中山大学）；Bucknell University（巴克内尔大学）；Toyo University（东洋大学）；Institute of Astronomy and Astrophysics, Academia Sinica（中央研究院天文及天文物理研究所）；National Radio Astronomy Observatory（美国国家射电天文台）
Ingyin Zaw, C. M. Violette Impellizzeri, Dominic W. Pesce, Elizabeth Humphreys, Hannah R. Stacey, Sophie Venselaar, Chengyu Kuo, Jack Gallimore, Yoshiaki Hagiwa… 展开作者
Ingyin Zaw, C. M. Violette Impellizzeri, Dominic W. Pesce, Elizabeth Humphreys, Hannah R. Stacey, Sophie Venselaar, Chengyu Kuo, Jack Gallimore, Yoshiaki Hagiwara, Satoki Matsushita, Jim Braatz
Water megamasers in the circumnuclear disks of active galactic nuclei are among the most precise probes of supermassive black holes. VLBI imaging of 22 GHz disk masers has provided geometric distances to independently constrain $H_0$, accurate black hole mass measurements, and sub-parsec views of accretion disk geometry. ALMA has opened a new window into water maser transitions in the sub-mm/mm regime, which trace temperatures, densities and disk regions that are inaccessible at 22 GHz, and can be observed at higher spatial resolution and with less free-free absorption. However, current detections are limited to a few bright extragalactic masers in nearby galaxies. We present the case for a next-generation sub-mm/mm interferometer - ALMA2040 - that would open a new parameter space for maser studies. We show that a 10-fold increase in line sensitivity and three times longer baselines compared to ALMA would transform sub-mm maser studies from a few bright detections into a population-level probe, delivering black hole masses and geometric distances from sub-mm masers alone, independent of and complementary to 22 GHz measurements. Integrated into a VLBI array, ALMA2040 would resolve maser disks out to $>$160 Mpc, extend maser black hole masses into the largely untested intermediate-mass regime, reveal magnetic field structure in accretion disks through polarization studies, and test systematics in $H_0$ measurements.
CosmicWeb-21cm array: A New Radio Observation Array Design for 21cm Cosmology
Yunnan Observatories, Chinese Academy of Sciences（中国科学院云南天文台）；Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences（中国科学院天体结构与演化重点实验室）；University of Chinese Academy of Sciences（中国科学院大学）；College of Information Engineering, Kunming University（昆明学院信息工程学院）；College of Big Data, Yunnan Agricultural University（云南农业大学大数据学院）；College of Physics and Electronic Engineering, Qujing Normal University（曲靖师范学院物理与电子工程学院）
Demonstration of a next-generation wavefront actuator for gravitational-wave detection
University of California, Riverside（加州大学河滨分校）；LIGO Laboratory, Massachusetts Institute of Technology（麻省理工学院LIGO实验室）；California Institute of Technology（加州理工学院）
The FarView Low Frequency Radio Array on the Moon's Far Side: Science and Array Architecture
University of Colorado Boulder（科罗拉多大学博尔德分校）；Arizona State University（亚利桑那州立大学）；California Institute of Technology（加州理工学院）；Space Science Institute（空间科学研究所）；National Radio Astronomy Observatory（美国国家射电天文台）；Brown University（布朗大学）；Lunar Resources, Inc.（月球资源公司）；CSIRO, Space & Astronomy（澳大利亚联邦科学与工业研究组织，太空与天文部）
