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Progress on Ultra-Heavy Cosmic-Ray Analysis with CALET on the International space Station 37

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Progress on Ultra-Heavy Cosmic-Ray Analysis with CALET on th...

37th International Cosmic Ray Conference, ICRC 2021

作者： Zober, Wolfgang V. Rauch, Brian F. Ficklin, Anthony W. Cannady, Nicholas Adriani, O. Akaike, Y. Asano, K. Asaoka, Y. Berti, E. Bigongiari, G. Binns, W.R. Bongi, M. Brogi, P. Bruno, A. Buckley, J.H. Cannady, N. Castellini, G. Checchia, C. Cherry, M.L. Collazuol, G. Ebisawa, K. Ficklin, A.W. Fuke, H. Gonzi, S. Guzik, T.G. Hams, T. Hibino, K. Ichimura, M. Ioka, K. Ishizaki, W. Israel, M.H. Kasahara, K. Kataoka, J. Kataoka, R. Katayose, Y. Kato, C. Kawanaka, N. Kawakubo, Y. Kobayashi, K. Kohri, K. Krawczynski, H.S. Krizmanic, J.F. Maestro, P. Marrocchesi, P.S. Messineo, A.M. Mitchell, J.W. Miyake, S. Moiseev, A.A. Mori, M. Mori, N. Motz, H.M. Munakata, K. Nakahira, S. Nishimura, J. de Nolfo, G.A. Okuno, S. Ormes, J.F. Ospina, N. Ozawa, S. Pacini, L. Papini, P. Rauch, B.F. Ricciarini, S.B. Sakai, K. Sakamoto, T. Sasaki, M. Shimizu, Y. Shiomi, A. Spillantini, P. Stolzi, F. Sugita, S. Sulaj, A. Takita, M. Tamura, T. Terasawa, T. Torii, S. Tsunesada, Y. Uchihori, Y. Vannuccini, E. Wefel, J.P. Yamaoka, K. Yanagita, S. Yoshida, A. Yoshida, K. Zober, W.V. Department of Physics McDonnell Center for the Space Sciences Washington University St. LouisMO63130 United States Department of Physics and Astronomy Louisiana State University Baton RougeLA70803 United States CRESST-II University of Maryland NASA Goddard Space Flight Center Baltimore County United States Department of Physics University of Florence Via Sansone 1 Sesto Fiorentino50019 Italy INFN Sezione di Florence Via Sansone 1 Sesto Fiorentino50019 Italy Waseda Research Institute for Science and Engineering Waseda University 17 Kikuicho Shinjuku Tokyo162-0044 Japan JEM Utilization Center Human Spaceflight Technology Directorate Japan Aerospace Exploration Agency 2-1-1 Sengen Ibaraki Tsukuba305-8505 Japan Institute for Cosmic Ray Research The University of Tokyo 5-1-5 Kashiwa-no-Ha Chiba Kashiwa277-8582 Japan Department of Physical Sciences Earth and Environment University of Siena via Roma 56 Siena53100 Italy INFN Sezione di Pisa Polo Fibonacci Largo B. Pontecorvo 3 Pisa56127 Italy Department of Physics McDonnell Center for the Space Sciences Washington University One Brookings Drive St. LouisMO63130-4899 United States Heliospheric Physics Laboratory NASA/GSFC GreenbeltMD20771 United States Department of Physics Catholic University of America WashingtonDC20064 United States Center for Space Sciences and Technology University of Maryland Baltimore County 1000 Hilltop Circle BaltimoreMD21250 United States Astroparticle Physics Laboratory NASA/GSFC GreenbeltMD20771 United States Center for Research and Exploration in Space Sciences and Technology NASA/GSFC GreenbeltMD20771 United States Via Madonna del Piano 10 Sesto Fiorentino50019 Italy Department of Physics and Astronomy Louisiana State University 202 Nicholson Hall Baton RougeLA70803 United States Department of Physics and Astronomy University of Padova Via Marzolo 8 Padova35131 Italy INFN Sezione di Padova Via Marzolo 8 Padova35131 Italy Insti

The Calorimetric Electron Telescope (CALET), launched to the International space Station in August 2015 and continuously operating since, measures cosmic-ray (CR) electrons, nuclei and gamma-rays. CALET utilizes its main calorimeter charge detector to measure CR nuclei from 1H to 40Zr. In order to maximize the acceptance of the rare ultra-heavy (UH) CR above 30Zn, a special high duty cycle (∼90%) UH trigger is used that does not require passage through the 27 radiation length deep Total Absorption Calorimeter (TASC). This provides a 6× increase in geometry factor allowing CALET to collect in 5 years a UHCR dataset with statistics comparable to those from the first flight of the balloon-borne SuperTIGER instrument but without the need for atmospheric corrections. Previous CALET UHCR analyses using time and position corrections based on 26Fe and a geomagnetic vertical cutoff rigidity selection have shown abundances of even nuclei in agreement with SuperTIGER. To further improve resolution and maximize statistics, a trajectory dependent geomagnetic rigidity selection has been employed here with further work being done to implement a Cash-Karp Runge-Kutta ray tracing method for an improved determination of effective cutoff rigidities. Additional work has also been done to analyze events from the smaller dataset of events that pass through the TASC, which provides energy information and a better charge assignment that will provide higher resolution UH measurements, albeit with lower statistics. © Copyright owned by the author(s).

关键词： Calorimeters

A survey of static formal methods for building dependable industrial automation systems

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arXiv 2021年

作者： Sinha, Roopak Patil, Sandeep Gomes, Luis Vyatkin, Valeriy Department of IT and Software Engineering Auckland University of Technology Auckland New Zealand Department of Computer Science Electrical and Space Engineering Luleå University of Technology Luleå97187 Sweden Electrical and Computer Engineering Department NOVA School of Science and Technology NOVA University of Lisbon Portugal Centre of Technology and Systems UNINOVA Caparica2829-517 Portugal Computer Technologies International Laboratory ITMO University Saint Petersburg197101 Russia Department of Electrical Engineering in Automation Aalto University Aalto00076 Finland

Industrial automation systems (IAS) need to be highly dependable;they should not merely function as expected but also do so in a reliable, safe, and secure manner. Formal methods are mathematical techniques that can greatly aid in developing dependable systems and can be used across all phases of the system development life cycle (SDLC), including requirements engineering, system design and implementation, verification and validation (testing), maintenance, and even documentation. This state-of-the-art survey reports existing formal approaches for creating more dependable IAS, focusing on static formal methods that are used before a system is completely implemented. We categorize surveyed works based on the phases of the SDLC, allowing us to identify research gaps and promising future directions for each phase. Copyright © 2021, The Authors. All rights reserved.

关键词： Formal verification

Nonlinear electronic stopping of negatively-charged particles in liquid water

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arXiv 2023年

作者： Koval, Natalia E. Da Pieve, Fabiana Gu, Bin Muñoz-Santiburcio, Daniel Kohanoff, Jorge Artacho, Emilio CIC Nanogune BRTA Tolosa Hiribidea 76 Donostia-San Sebastián Spain Royal Belgian Institute for Space Aeronomy Brussels Belgium Atomistic Simulation Centre Queen's University Belfast BelfastBT7 1NN United Kingdom Department of Physics Nanjing University of Information Science and Technology Nanjing210044 China Instituto de Fusión Nuclear "Guillermo Velarde" Universidad Politécnica de Madrid Spain CIC Nanogune BRTA and DIPC Tolosa Hiribidea 76 San Sebastián20018 Spain Theory of Condensed Matter Cavendish Laboratory University of Cambridge J. J. Thomson Avenue CambridgeCB3 0HE United Kingdom Ikerbasque Basque Foundation for Science Bilbao48011 Spain

We present real-time time-dependent density-functional-theory calculations of the electronic stopping power for negative and positive projectiles (electrons, protons, antiprotons and muons) moving through liquid water. After correction for finite mass effects, the nonlinear stopping power obtained in this work is significantly different from the previously known results from semi-empirical calculations based on the dielectric response formalism. Linear-nonlinear discrepancies are found both in the maximum value of the stopping power and the Bragg peak's position. Our results indicate the importance of the nonlinear description of electronic processes, particularly for electron projectiles, which are modeled here as classical point charges. Our findings also confirm the expectation that the quantum nature of the electron projectile should substantially influence the stopping power around the Bragg peak and below. Copyright © 2023, The Authors. All rights reserved.

关键词： Projectiles

Arbitrary high-order linear structure-preserving schemes for the regularized long-wave equation

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arXiv 2021年

作者： Jiang, Chaolong Qian, Xu Song, Songhe Cui, Jin Department of Mathematics College of Liberal Arts and Science National University of Defense Technology Changsha410073 China School of Statistics and Mathematics Yunnan University of Finance and Economics Kunming650221 China Department of Basic Sciences Nanjing Vocational College of Information Technology Nanjing210023 China Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems School of Mathematical Sciences Nanjing Normal University Nanjing210023 China

In this paper, a class of arbitrarily high-order linear momentum-preserving and energy-preserving schemes are proposed, respectively, for solving the regularized long-wave equation. For the momentum-preserving scheme, the key idea is based on the extrapolation/prediction-correction technique and the symplectic Runge-Kutta method in time, together with the standard Fourier pseudo-spectral method in space. We show that the scheme is linear, high-order, unconditionally stable and preserves the discrete momentum of the system. For the energy-preserving scheme, it is mainly based on the energy quadratization approach and the analogous linearized strategy used in the construction of the linear momentum-preserving scheme. The proposed scheme is linear, high-order and can preserve a discrete quadratic energy exactly. Numerical results are addressed to demonstrate the accuracy and efficiency of the proposed scheme. Copyright © 2021, The Authors. All rights reserved.

关键词： Runge Kutta methods

JWST NIRCam Defocused Imaging: Photometric Stability Performance and How it Can Sense Mirror Tilts

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arXiv 2022年

作者： Schlawin, Everett Beatty, Thomas Brooks, Brian Nikolov, Nikolay K. Greene, Thomas P. Espinoza, Néstor Glidic, Kayli Baka, Keith Egami, Eiichi Stansberry, John Boyer, Martha Gennaro, Mario Leisenring, Jarron Hilbert, Bryan Misselt, Karl Kelly, Doug Canipe, Alicia Beichman, Charles Correnti, Matteo Knight, J. Scott Jurling, Alden Perrin, Marshall D. Feinberg, Lee D. McElwain, Michael W. Bond, Nicholas Ciardi, David Kendrew, Sarah Rieke, Marcia Steward Observatory 933 North Cherry Avenue TucsonAZ85721 United States Department of Astronomy University of Wisconsin Madison MadisonWI53706 United States Space Telescope Science Institute 3700 San Martin Drive BaltimoreMD21218 United States NASA Ames Research Center Space Science and Astrobiology Division MS 245-6 Moffett FieldCA94035 United States Department of Physics & Astronomy Johns Hopkins University BaltimoreMD2121818 United States Anton Pannekoek Institute University of Amsterdam Science Park 904 Amsterdam1098 XH Netherlands Department of Physics Astronomy Johns Hopkins University 3400 North Charles Street BaltimoreMD21218 United States NASA Exoplanet Science Institute IPAC Jet Propulsion Laboratory California Institute of Technology 1200 E California Blvd PasadenaCA91125 United States Ball Aerospace & technologies Corp 1600 Commerce Street BoulderCO80301 United States NASA Goddard Space Flight Center 8800 Greenbelt Rd GreenbeltMD20771 United States ADNET Systems Inc./Code 550 NASA’s Goddard Space Flight Center GreenbeltMD20771 United States European Space Agency Space Telescope Science Institute 3700 San Martin Drive BaltimoreMD21218 United States

We use JWST NIRCam short wavelength photometry to capture a transit lightcurve of the exoplanet HAT-P-14 b to assess performance as part of instrument commissioning. The short wavelength precision is 152 ppm per 27 second integration as measured over the full time series compared to a theoretical limit of 107 ppm, after corrections to spatially correlated 1/f noise. Persistence effects from charge trapping are well fit by an exponential function with short characteristic timescales, settling on the order of 5-15 minutes. The short wavelength defocused photometry is also uniquely well suited to measure the realtime wavefront error of JWST. Analysis of the images and reconstructed wavefront maps indicate that two different hexagonal primary mirror segments exhibited "tilt events" where they changed orientation rapidly in less than ∼1.4 seconds. In some cases, the magnitude and timing of the flux jumps caused by tilt events can be accurately predicted with a telescope model. These tilt events can be sensed by simultaneous longer-wavelength NIRCam grism spectral images alone in the form of changes to the point spread function, diagnosed from the FWHM. They can also be sensed with the FGS instrument from difference images. Tilt events possibly from sudden releases of stress in the backplane structure behind the mirrors were expected during the commissioning period because they © 2022, CC BY.

关键词： Wavefronts

Venus as an Exoplanet: I. An Initial Exploration of the 3-D Energy Balance for a CO2 Exoplanetary Atmosphere Around an M-Dwarf Star

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arXiv 2022年

作者： Parkinson, Christopher D. Bougher, Stephen W. Mills, Franklin P. Brecht, Amanda Li, James Yung, Yuk L. Hu, Renyu Gronoff, Guillaume Space Science Institute 4765 Walnut St Suite B BoulderCO80301 United States Division of Geological and Planetary Sciences California Institute of Technology CA United States Climate and Space Sciences and Engineering Department University of Michigan 2455 Hayward Street Ann ArborMI48109 United States Fenner School of Environment & Society Australian National University Canberra Australia McDonald Observatory University of Texas Austin AustinTX78712 United States NASA Ames Research Center Moffett FieldCA United States Jet Propulsion Laboratory CA United States LARC-E303 Science Systems & Applications Inc

The chemical evolution of an exoplanetary Venus-like atmosphere is dependent upon the ultraviolet to near ultraviolet (FUV-NUV) radiation ratio from the parent star, the balance between CO2 photolysis and recombination via reactions that depend on the water abundance, and various catalytic chemical cycles. In this study, we use a three-dimensional (3-D) model to simulate conditions for a Venus-like exoplanet orbiting the M-dwarf type star GJ436 by varying the star/planet distance and considering the resultant effects on heating/cooling and dynamics. The simulation includes the middle and upper atmosphere (-5 mbar. More specifically, CO2 15-μm cooling balances EUV/UV and Near InfraRed (NIR) heating at altitudes below 10-7 mbar pressure with a strong maximum balance for pressures at ~10-5 mbar, thus explaining the invariance of the temperature distribution at altitudes below 10-5 mbar pressure for all cases. Our model comparisons also show that moderate changes in NIR heating result in relatively small changes in neutral temperature in the upper atmosphere, and virtually no change in the middle atmosphere. However, with larger changes in the NIR heating profile, much greater changes in neutral temperature occur in the entire upper and middle atmosphere studied. © 2022, CC BY.

关键词： Infrared devices

The science Performance of JWST as Characterized in Commissioning

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arXiv 2022年

作者： Rigby, Jane Perrin, Marshall McElwain, Michael Kimble, Randy Friedman, Scott Lallo, Matt Doyon, René Feinberg, Lee Ferruit, Pierre Glasse, Alistair Rieke, Marcia Rieke, George Wright, Gillian Willott, Chris Colon, Knicole Milam, Stefanie Neff, Susan Stark, Christopher Valenti, Jeff Abell, Jim Abney, Faith Abul-Huda, Yasin Acton, D. Scott Adams, Evan Adler, David Aguilar, Jonathan Ahmed, Nasif Albert, Loïc Alberts, Stacey Aldridge, David Allen, Marsha Altenburg, Martin Álvarez-Márquez, Javier de Oliveira, Catarina Alves Andersen, Greg Anderson, Harry Anderson, Sara Argyriou, Ioannis Armstrong, Amber Arribas, Santiago Artigau, Etienne Arvai, Amanda Atkinson, Charles Bacon, Gregory Bair, Thomas Banks, Kimberly Barrientes, Jaclyn Barringer, Bruce Bartosik, Peter Bast, William Baudoz, Pierre Beatty, Thomas Bechtold, Katie Beck, Tracy Bergeron, Eddie Bergkoetter, Matthew Bhatawdekar, Rachana Birkmann, Stephan Blazek, Ronald Blome, Claire Boccaletti, Anthony Böker, Torsten Boia, John Bonaventura, Nina Bond, Nicholas Bosley, Kari Boucarut, Ray Bourque, Matthew Bouwman, Jeroen Bower, Gary Bowers, Charles Boyer, Martha Bradley, Larry Brady, Greg Braun, Hannah Breda, David Bresnahan, Pamela Bright, Stacey Britt, Christopher Bromenschenkel, Asa Brooks, Brian Brooks, Keira Brown, Bob Brown, Matthew Brown, Patricia Bunker, Andy Burger, Matthew Bushouse, Howard Cale, Steven Cameron, Alex Cameron, Peter Canipe, Alicia Caplinger, James Caputo, Francis Cara, Mihai Carey, Larkin Carniani, Stefano Carrasquilla, Maria Carruthers, Margaret Case, Michael Catherine, Riggs Chance, Don Chapman, George Charlot, Stéphane Charlow, Brian Chayer, Pierre Chen, Bin Cherinka, Brian Chichester, Sarah Chilton, Zack Chonis, Taylor Clampin, Mark Clark, Charles Clark, Kerry Coe, Dan Coleman, Benee Comber, Brian Comeau, Tom Connolly, Dennis Cooper, James Cooper, Rachel Coppock, Eric Correnti, Matteo Cossou, Christophe Coulais, Alain Coyle, Laura Cracraft, Misty Curti, Mirko Cuturic, Steven Davis, Katherine Davis, Michael Dean, Bruce DeLisa, Amy deMeest NASA's Goddard Space Flight Center United States Space Telescope Science Institute United States Université de Montréal Canada European Space Agency United Kingdom UK Astronomy Technology Centre United Kingdom University of Arizona United States Canada Ball Aerospace United States Honeywell International United States Airbus Defence and Space GmbH Germany Spain Katholieke Universiteit Leuven Belgium Northrop Grumman Space Systems United States Observatoire de Paris France Niels Bohr Institute Denmark Max-Planck-Institut für Astronomie Germany Jet Propulsion Laboratory California Institute of Technology United States University of Oxford United Kingdom Scuola Normale Superiore di Pisa Italy Institut d'Astrophysique de Paris France Commissariat à l'énergie Atomique et aux énergies Alternatives France University of Cambridge United Kingdom Canadian Space Agency Canada Center for Astrophysics | Harvard & Smithsonian United States Rutherford Appleton Laboratory United Kingdom Lockheed Martin Advanced Technology Center United States ATG Europe for the European Space Agency Netherlands Eidgenössische Technische Hochschule Switzerland NASA's Ames Research Center United States Association of Universities for Research in Astronomy United States National Aeronautics and Space Administration United States University of California Santa Cruz United States University of Copenhagen Denmark Dublin Institute for Advanced Studies Ireland AURA for the European Space Agency United States Telespazio UK for the European Space Agency United Kingdom Aurora Technology for the European Space Agency Netherlands Quantum Circuits United States University of Groningen Netherlands ATA Aerospace United States Heliospace United States NASA's Johnson Space Center United States John Hopkins University United States Princeton University United States University of Leicester United Kingdom

This paper characterizes the actual science performance of the James Webb space Telescope (JWST), as determined from the six month commissioning period. We summarize the performance of the spacecraft, telescope, science instruments, and ground system, with an emphasis on differences from pre-launch expectations. Commissioning has made clear that JWST is fully capable of achieving the discoveries for which it was built. Moreover, almost across the board, the science performance of JWST is better than expected;in most cases, JWST will go deeper faster than expected. The telescope and instrument suite have demonstrated the sensitivity, stability, image quality, and spectral range that are necessary to transform our understanding of the cosmos through observations spanning from near-earth asteroids to the most distant galaxies. © 2022, CC BY.

关键词： Asteroids

A global product of fine-scale urban building height based on spaceborne lidar

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arXiv 2023年

作者： Ma, Xiao Zheng, Guang Xu, Chi Moskal, L. Monika Gong, Peng Guo, Qinghua Huang, Huabing Li, Xuecao Pang, Yong Wang, Cheng Xie, Huan Yu, Bailang Zhao, Bo Zhou, Yuyu School of Life Sciences Nanjing University Nanjing210023 China International Institute for Earth System Sciences Nanjing University Nanjing210023 China School of Environment and Forest Sciences University of Washington Box 352100 SeattleWA98195 United States Urban Systems Institute Department of Geography and Earth Sciences University of Hong Kong 999077 Hong Kong Institute of Remote Sensing and Geographical Information Systems School of Earth and Space Sciences Peking University Beijing100871 China Zhuhai519082 China College of Land Science and Technology China Agricultural University Beijing100083 China Institute of Forest Resource Information Techniques Chinese Academy of Forestry Beijing100091 China Key Laboratory of Digital Earth Science Aerospace Information Research Institute Chinese Academy of Sciences Beijing100094 China College of Surveying and Geo-Informatics Shanghai Key Laboratory of Space Mapping and Remote Sensing for Planetary Exploration Tongji University Shanghai200092 China School of Geographic Sciences East China Normal University Shanghai200241 China Department of Geography University of Washington Smith Hall 408 Box 353550 SeattleWA98195 United States

Characterizing urban environments with broad coverages and high precision is more important than ever for achieving the UN's Sustainable Development Goals (SDGs) as half of the world's populations are living in cities. Urban building height as a fundamental 3D urban structural feature has far-reaching applications. However, so far, producing readily available datasets of recent urban building heights with fine spatial resolutions and global coverages remains a challenging task. Here, we provide an up-to-date global product of urban building heights based on a fine grid size of 150 m around 2020 by combining the spaceborne lidar instrument of GEDI and multi-sourced data including remotely sensed images (i.e., Landsat-8, Sentinel-2, and Sentinel-1) and topographic data. Our results revealed that the estimated method of building height samples based on the GEDI data was effective with 0.78 of Pearson's r and 3.67 m of RMSE in comparison to the reference data. The mapping product also demonstrated good performance as indicated by its strong correlation with the reference data (i.e., Pearson's r = 0.71, RMSE = 4.60 m). Compared with the currently existing products, our global urban building height map holds the ability to provide a higher spatial resolution (i.e., 150 m) with a great level of inherent details about the spatial heterogeneity and flexibility of updating using the GEDI samples as inputs. This work will boost future urban studies across many fields including climate, environmental, ecological, and social sciences. Copyright © 2023, The Authors. All rights reserved.

关键词： Optical radar

CATCH: Chasing All Transients Constellation Hunters space Mission

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arXiv 2022年

作者： Li, Panping Yin, Qian-Qing Li, Zhengwei Tao, Lian Wen, Xiangyang Zhang, Shuang-Nan Qi, Liqiang Zhang, Juan Zhao, Donghua Li, Dalin Yu, Xizheng Bu, Qingcui Chen, Wen Chen, Yupeng Huang, Yiming Huang, Yue Jin, Ge Li, Gang Liu, Hongbang Liu, Xiaojing Ma, Ruican Peng, Wenxi Tang, Ruijing Wang, Yusa Xiao, Jingyu Xiong, Shaolin Yang, Sheng Yang, Yanji Zhang, Chen Zhang, Tianchong Zhang, Liang Zhang, Xuan Zhao, Haisheng Zhao, Kang Zhao, Qingchang Zhao, Shujie Zhou, Xing Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing100049 China University of Chinese Academy of Sciences Chinese Academy of Sciences Beijing100049 China National Astronomical Observatories Chinese Academy of Sciences Beijing100101 China Key Laboratory of Electronics and Information Technology for Space Systems National Space Science Center Chinese Academy of Sciences Beijing100190 China Institut für Astronomie und Astrophysik Kepler Center for Astro and Particle Physics Eberhard Karls Universität Sand 1 Tübingen72076 Germany Innovation Academy for Microsatellites Chinese Academy of Sciences Shanghai200135 China North Night Vision Science & Technology Research Institute Group Co. Ltd. Nanjing211100 China Guangxi University Nanning530004 China Beijing Jiaotong University Beijing100044 China Nanchang University Nanchang330031 China

In time-domain astronomy, a substantial number of transients will be discovered by multi-wavelength and multi-messenger observatories, posing a great challenge for follow-up capabilities. We have thus proposed an intelligent X-ray constellation, the Chasing All Transients Constellation Hunters (CATCH) space mission. Consisting of 126 micro-satellites in three types, CATCH will have the capability to perform follow-up observations for a large number of different types of transients simultaneously. Each satellite in the constellation will carry lightweight X-ray optics and use a deployable mast to increase the focal length. The combination of different optics and detector systems enables different types of satellites to have multiform observation capabilities, including timing, spectroscopy, imaging, and polarization. Controlled by the intelligent system, different satellites can cooperate to perform uninterrupted monitoring, all-sky follow-up observations, and scanning observations with a flexible field of view (FOV) and multi-dimensional observations. Therefore, CATCH will be a powerful mission to study the dynamic universe. Here, we present the current design of the spacecraft, optics, detector system, constellation configuration and observing modes, as well as the development plan. Copyright © 2022, The Authors. All rights reserved.

关键词： Satellites