检索结果-内蒙古大学图书馆

Patterns of somatic structural variation in human cancer genomes (vol 578, pg 112, 2020)

NATURE 2023年第7948期614卷 E38-E38页

作者： Li, Yilong Roberts, Nicola D. Wala, Jeremiah A. Shapira, Ofer Schumacher, Steven E. Kumar, Kiran Khurana, Ekta Waszak, Sebastian Korbel, Jan O. Haber, James E. Imielinski, Marcin Weischenfeldt, Joachim Beroukhim, Rameen Campbell, Peter J. Cancer Genome Project Wellcome Trust Sanger Institute Hinxton UK Totient Inc Cambridge MA USA Wellcome Sanger Institute Wellcome Genome Campus Hinxton UK Department of Haematology University of Cambridge Cambridge UK Cambridge University Hospitals NHS Foundation Trust Cambridge UK Korea Advanced Institute of Science and Technology Daejeon South Korea Department of Zoology Genetics and Physical Anthropology University of Santiago de Compostela Santiago de Compostela Spain Centre for Research in Molecular Medicine and Chronic Diseases (CIMUS) University of Santiago de Compostela Santiago de Compostela Spain The Biomedical Research Centre (CINBIO) University of Vigo Vigo Spain Centre for Research in Molecular Medicine and Chronic Diseases (CiMUS) Universidade de Santiago de Compostela Santiago de Compostela Spain Department of Zoology Genetics and Physical Anthropology (CiMUS) Universidade de Santiago de Compostela Santiago de Compostela Spain The Biomedical Research Centre (CINBIO) Universidade de Vigo Vigo Spain The Broad Institute of Harvard and MIT Cambridge MA USA Bioinformatics and Integrative Genomics Harvard University Cambridge MA USA Department of Cancer Biology Dana-Farber Cancer Institute Boston MA USA Broad Institute of MIT and Harvard Cambridge MA USA Department of Medical Oncology Dana-Farber Cancer Institute Boston MA USA Harvard Medical School Boston MA USA Massachusetts General Hospital Center for Cancer Research Charlestown MA USA Dana-Farber Cancer Institute Boston MA USA Department of Biostatistics and Computational Biology Dana-Farber Cancer Institute and Harvard Medical School Boston MA USA Weill Cornell Medical College New York NY USA Department of Physiology and Biophysics Weill Cornell Medicine New York NY USA Institute for Computational Biomedicine Weill Cornell Medicine New York NY USA Controlled Department and Institution New York NY USA Englander Institute for Precision Medicine Weill Cornell Medicine Ne

来源：评论

学校读者我要写书评

暂无评论

Extended calculations of energy levels, radiative properties, and lifetimes for oxygen-like Mo XXXV

arXiv

引用

arXiv 2019年

作者： Wang, Kai Zheng, Wei Zhao, Xiao Hui Chen, Zhan Bin Chen, Chong Yang Yan, Jun Hebei Key Lab of Optic-electronic Information and Materials College of Physics Science and Technology Hebei University Baoding071002 China Shanghai EBIT Lab Key Laboratory of Nuclear Physics and Ion-beam Application Institute of Modern Physics Department of Nuclear Science and Technology Fudan University Shanghai200433 China School of Science Hunan University of Technology Zhuzhou412007 China Institute of Applied Physics and Computational Mathematics Beijing100088 China

Employing two state-of-the-art methods, second-order many-body perturbation theory and multiconfiguration Dirac-Fock, highly accurate calculations are performed for the lowest 318 fine-structure levels arising from the 2s22p4, 2s2p5, 2p6, 2s22p33l, 2s2p43l, 2p53l, and 2s22p34l configurations in O-like Mo XXXV. Complete and consistent atomic data, including excitation energies, lifetimes, wavelengths, and E1, E2, M1 line strengths, oscillator strengths, and transition rates among these 318 levels are provided. Comparisons are made between the present two data sets, as well as with other available experimental and theoretical values. The present data are accurate enough for identification and deblending of emission lines involving the n = 3, 4 levels and are also useful for modeling and diagnosing fusion plasmas. These data can be considered as a benchmark for other calculations. Copyright © 2019, The Authors. All rights reserved.

关键词： Oxygen

来源：评论

学校读者我要写书评

暂无评论

The putative center in NGC 1052

arXiv

引用

arXiv 2025年

作者： Baczko, Anne-Kathrin Kadler, Matthias Ros, Eduardo Fromm, Christian M. Wielgus, Maciek Perucho, Manel Krichbaum, Thomas P. Baloković, Mislav Blackburn, Lindy Chan, Chi-Kwan Issaoun, Sara Janssen, Michael Ricci, Luca Akiyama, Kazunori Albentosa-Ruíz, Ezequiel Alberdi, Antxon Alef, Walter Algaba, Juan Carlos Anantua, Richard Asada, Keiichi Azulay, Rebecca Bach, Uwe Ball, David Bandyopadhyay, Bidisha Barrett, John Bauböck, Michi Benson, Bradford A. Bintley, Dan Blundell, Raymond Bouman, Katherine L. Bower, Geoffrey C. Boyce, Hope Bremer, Michael Brinkerink, Christiaan D. Brissenden, Roger Britzen, Silke Broderick, Avery E. Broguiere, Dominique Bronzwaer, Thomas Bustamante, Sandra Byun, Do-Young Carlstrom, John E. Ceccobello, Chiara Chael, Andrew Chang, Dominic O. Chatterjee, Koushik Chatterjee, Shami Chen, Ming-Tang Chen, Yongjun Cheng, Xiaopeng Cho, Ilje Christian, Pierre Conroy, Nicholas S. Conway, John E. Cordes, James M. Crawford, Thomas M. Crew, Geoffrey B. Cruz-Osorio, Alejandro Cui, Yuzhu Dahale, Rohan Davelaar, Jordy De Laurentis, Mariafelicia Deane, Roger Dempsey, Jessica Desvignes, Gregory Dexter, Jason Dhruv, Vedant Dihingia, Indu K. Doeleman, Sheperd S. Dougall, Sean Taylor Dzib, Sergio A. Eatough, Ralph P. Emami, Razieh Falcke, Heino Farah, Joseph Fish, Vincent L. Fomalont, Edward Ford, H. Alyson Foschi, Marianna Fraga-Encinas, Raquel Freeman, William T. Friberg, Per Fuentes, Antonio Galison, Peter Gammie, Charles F. García, Roberto Gentaz, Olivier Georgiev, Boris Goddi, Ciriaco Gold, Roman Gómez-Ruiz, Arturo I. Gómez, José L. Gu, Minfeng Gurwell, Mark Hada, Kazuhiro Haggard, Daryl Haworth, Kari Hecht, Michael H. Hesper, Ronald Heumann, Dirk Ho, Luis C. Ho, Paul Honma, Mareki Huang, Chih-Wei L. Huang, Lei Hughes, David H. Impellizzeri, C.M. Violette Inoue, Makoto James, David J. Jannuzi, Buell T. Jeter, Britton Jiang, Wu Jiménez-Rosales, Alejandra Johnson, Michael D. Jorstad, Svetlana Joshi, Abhishek V. Jung, Taehyun Karami, Mansour Karuppusamy, Ramesh Kawashima, Tomohisa Keating, Garrett K. Kettenis, M Department of Space Earth and Environment Chalmers University of Technology GothenburgSE-41296 Sweden Max-Planck-Institut für Radioastronomie Auf dem Hügel 69 BonnD-53121 Germany Institut für Theoretische Physik und Astrophysik Universität Würzburg Emil-Fischer-Str. 31 WürzburgD-97074 Germany Institut für Theoretische Physik Goethe-Universität Frankfurt Max-von-Laue-Straße 1 Frankfurt am MainD-60438 Germany Departament d'Astronomia i Astrofísica Universitat de València C. Dr. Moliner 50 Burjassot ValènciaE-46100 Spain Observatori Astronòmic Universitat de València C. Catedrático José Beltrán 2 Paterna ValènciaE-46980 Spain Yale Center for Astronomy & Astrophysics Yale University 52 Hillhouse Avenue New HavenCT06511 United States Black Hole Initiative Harvard University 20 Garden Street CambridgeMA02138 United States Center for Astrophysics Harvard & Smithsonian 60 Garden Street CambridgeMA02138 United States Steward Observatory Department of Astronomy University of Arizona 933 N. Cherry Ave. TucsonAZ85721 United States Data Science Institute University of Arizona 1230 N. Cherry Ave. TucsonAZ85721 United States Program in Applied Mathematics University of Arizona 617 N. Santa Rita TucsonAZ85721 United States Radboud University PO Box 9010 Nijmegen6500 GL Netherlands Massachusetts Institute of Technology Haystack Observatory 99 Millstone Road WestfordMA01886 United States National Astronomical Observatory of Japan 2-21-1 Osawa Mitaka Tokyo181-8588 Japan Instituto de Astrofísica de Andalucía-CSIC Glorieta de la Astronomía s/n GranadaE-18008 Spain Department of Physics Faculty of Science Universiti Malaya Kuala Lumpur50603 Malaysia Department of Physics & Astronomy The University of Texas at San Antonio One UTSA Circle San AntonioTX78249 United States Institute of Astronomy and Astrophysics Academia Sinica 11F of Astronomy-Mathematics Building AS/NTU No. 1 Sec. 4 Roosevelt Rd. Taipei10617 Taiwan Astronomy Depart

Context. Many active galaxies harbor powerful relativistic jets, however, the detailed mechanisms of their formation and acceleration remain poorly understood. Aims. To investigate the area of jet acceleration and collimation with the highest available angular resolution, we study the innermost region of the bipolar jet in the nearby low-ionization nuclear emission-line region (LINER) galaxy NGC 1052. Methods. We combined observations of NGC 1052 taken with VLBA, GMVA, and EHT over one week in the spring of 2017. Our study is focused on the size and continuum spectrum of the innermost region containing the central engine and the footpoints of both jets. We employed a synchrotron-self absorption model to fit the continuum radio spectrum and we combined the size measurements from close to the central engine out to ∼1 pc to study the jet collimation. Results. For the first time, NGC 1052 was detected with the EHT, providing a size of the central region in-between both jet bases of 43 µas perpendicular to the jet axes, corresponding to just around 250 RS (Schwarzschild radii). This size estimate supports previous studies of the jets expansion profile which suggest two breaks of the profile at around 3 × 103 RS and 1 × 104 RS distances to the core. Furthermore, we estimated the magnetic field to be 1.25 Gauss at a distance of 22 µas from the central engine by fitting a synchrotron-self absorption spectrum to the innermost emission feature, which shows a spectral turn-over at ∼130 GHz. Assuming a purely poloidal magnetic field, this implies an upper limit on the magnetic field strength at the event horizon of 2.6 × 104 Gauss, which is consistent with previous measurements. Conclusions. The complex, low-brightness, double-sided jet structure in NGC 1052 makes it a challenge to detect the source at millimeter (mm) wavelengths. However, our first EHT observations have demonstrated that detection is possible up to at least 230 GHz. This study offers a glimpse through the dens

关键词： Synchrotrons

来源：评论

学校读者我要写书评

暂无评论

Free-energy landscapes of DNA and its assemblies: Perspectives from coarse-grained modelling

arXiv

引用

arXiv 2021年

作者： Doye, Jonathan P.K. Louis, Ard A. Schreck, John S. Romano, Flavio Harrison, Ryan M. Mosayebi, Majid Engel, Megan C. Ouldridge, Thomas E. Physical and Theoretical Chemistry Laboratory Department of Chemistry University of Oxford OxfordOX1 3QZ United Kingdom Rudolf Peierls Centre for Theoretical Physics University of Oxford Parks Road OxfordOX1 3PU United Kingdom National Center for Atmospheric Research Computational and Information Systems Laboratory 850 Table Mesa Drive BoulderCO80305 United States Dipartimento di Scienze Molecolari e Nanosistemi Università Ca' Foscari di Venezia via Torino 155 Venezia Mestre30170 Italy School of Mathematics University of Bristol BristolBS8 1QU United Kingdom School of Engineering and Applied Sciences Harvard University 29 Oxford Street CambridgeMA02138 United States Department of Bioengineering and Centre for Synthetic Biology Imperial College London LondonSW7 2AZ United Kingdom

This chapter will provide an overview of how characterizing free-energy landscapes can provide insights into the biophysical properties of DNA, as well as into the behaviour of the DNA assemblies used in the field of DNA nanotechnology. The landscapes for these complex systems are accessible through the use of accurate coarse-grained descriptions of DNA. Particular foci will be the landscapes associated with DNA self-assembly and mechanical deformation, where the latter can arise from either externally imposed forces or internal stresses. © 2021, CC BY.

关键词： DNA

来源：评论

学校读者我要写书评

暂无评论

Euclid: Searches for strong gravitational lenses using convolutional neural nets in Early Release Observations of the Perseus field

arXiv

引用

arXiv 2024年

作者： Pearce-Casey, R. Nagam, B.C. Wilde, J. Busillo, V. Ulivi, L. Andika, I.T. Manjón-García, A. Leuzzi, L. Matavulj, P. Serjeant, S. Walmsley, M. Barroso, J.A. Acevedo O’Riordan, C.M. Clément, B. Tortora, C. Collett, T.E. Courbin, F. Gavazzi, R. Metcalf, R.B. Cabanac, R. Courtois, H.M. Crook-Mansour, J. Delchambre, L. Despali, G. Ecker, L.R. Franco, A. Holloway, P. Jahnke, K. Mahler, G. Marchetti, L. Melo, A. Meneghetti, M. Müller, O. Nucita, A.A. Pearson, J. Rojas, K. Scarlata, C. Schuldt, S. Sluse, D. Suyu, S.H. Vaccari, M. Vegetti, S. Verma, A. Vernardos, G. Bolzonella, M. Kluge, M. Saifollahi, T. Schirmer, M. Stone, C. Paulino-Afonso, A. Bazzanini, L. Hogg, N.B. Koopmans, L.V.E. Kruk, S. Mannucci, F. Bromley, J.M. Díaz-Sánchez, A. Dickinson, H.J. Powell, D.M. Bouy, H. Laureijs, R. Altieri, B. Amara, A. Andreon, S. Baccigalupi, C. Baldi, M. Balestra, A. Bardelli, S. Battaglia, P. Bonino, D. Branchini, E. Brescia, M. Brinchmann, J. Caillat, A. Camera, S. Capobianco, V. Carbone, C. Carretero, J. Casas, S. Castellano, M. Castignani, G. Cavuoti, S. Cimatti, A. Colodro-Conde, C. Congedo, G. Conselice, C.J. Conversi, L. Copin, Y. Cropper, M. Da Silva, A. Degaudenzi, H. De Lucia, G. Di Giorgio, A.M. Dinis, J. Dubath, F. Dupac, X. Dusini, S. Farina, M. Farrens, S. Faustini, F. Ferriol, S. Frailis, M. Franceschi, E. Galeotta, S. George, K. Gillard, W. Gillis, B. Giocoli, C. Gómez-Alvarez, P. Grazian, A. Grupp, F. Haugan, S.V.H. Holmes, W. Hook, I. Hormuth, F. Hornstrup, A. Hudelot, P. Jhabvala, M. Joachimi, B. Keihänen, E. Kermiche, S. Kiessling, A. Kilbinger, M. Kubik, B. Kümmel, M. Kunz, M. Kurki-Suonio, H. Le Mignant, D. Ligori, S. Lilje, P.B. Lindholm, V. Lloro, I. Maiorano, E. Mansutti, O. Marggraf, O. Markovic, K. Martinelli, M. Martinet, N. Marulli, F. Massey, R. Medinaceli, E. Mei, S. Melchior, M. Mellier, Y. Merlin, E. Meylan, G. Moresco, M. Moscardini, L. Nakajima, R. School of Physical Sciences The Open University Milton KeynesMK7 6AA United Kingdom Kapteyn Astronomical Institute University of Groningen PO Box 800 Groningen9700 AV Netherlands INAF-Osservatorio Astronomico di Capodimonte Via Moiariello 16 Napoli80131 Italy Department of Physics "E. Pancini" University Federico II Via Cinthia 6 Napoli80126 Italy INFN section of Naples Via Cinthia 6 Napoli80126 Italy University of Trento Via Sommarive 14 TrentoI-38123 Italy Dipartimento di Fisica e Astronomia Università di Firenze via G. Sansone 1 Sesto Fiorentino Firenze50019 Italy INAF-Osservatorio Astrofisico di Arcetri Largo E. Fermi 5 Firenze50125 Italy Technical University of Munich TUM School of Natural Sciences Physics Department James-Franck-Str. 1 Garching85748 Germany Max-Planck-Institut für Astrophysik Karl-Schwarzschild-Str. 1 Garching85748 Germany Departamento Física Aplicada Universidad Politécnica de Cartagena Campus Muralla del Mar Murcia Cartagena30202 Spain Dipartimento di Fisica e Astronomia "Augusto Righi" Alma Mater Studiorum Università di Bologna via Piero Gobetti 93/2 Bologna40129 Italy INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna Via Piero Gobetti 93/3 Bologna40129 Italy University of Applied Sciences and Arts of Northwestern Switzerland School of Engineering Windisch5210 Switzerland Department of Astronomy & Astrophysics University of Toronto 50 St George Street TorontoONM5S 3H4 Canada Jodrell Bank Centre for Astrophysics Department of Physics and Astronomy University of Manchester Oxford Road ManchesterM13 9PL United Kingdom Observatoire de Sauverny Versoix1290 Switzerland Lausanne1015 Switzerland Institute of Cosmology and Gravitation University of Portsmouth PortsmouthPO1 3FX United Kingdom Martí i Franquès 1 Barcelona08028 Spain Passeig de Lluís Companys 23 Barcelona08010 Spain Aix-Marseille Université CNRS CNES LAM Marseille France Institut d’Astrophysique de Paris UMR 709

The Euclid Wide Survey (EWS) is predicted to find approximately 170 000 galaxy-galaxy strong lenses from its lifetime observation of 14 000 deg2 of the sky. Detecting this many lenses by visual inspection with professional astronomers and citizen scientists alone is infeasible. As a result, machine learning algorithms, particularly convolutional neural networks (CNNs), have been used as an automated method of detecting strong lenses, and have proven fruitful in finding galaxy-galaxy strong lens candidates, such that the usage of CNNs in lens identification has increased. We identify the major challenge to be the automatic detection of galaxy-galaxy strong lenses while simultaneously maintaining a low false positive rate, thus producing a pure and complete sample of strong lens candidates from Euclid with a limited need for visual inspection. One aim of this research is to have a quantified starting point on the achieved purity and completeness with our current version of CNN-based detection pipelines for the VIS images of EWS. This work is vital in preparing our CNN-based detection pipelines to be able to produce a pure sample of the > 100 000 strong gravitational lensing systems widely predicted for Euclid. We select all sources with VIS IE 5 lensing systems in Euclid, this implies 106 objects for human classification, which while very large is not in principle intractable and not without precedent. © 2024, CC BY.

关键词： Convolutional neural networks

来源：评论

学校读者我要写书评

暂无评论

The effect of Coulomb field on laser-induced ultrafast imaging methods

arXiv

引用

arXiv 2019年

作者： Hao, XiaoLei Bai, YuXing Zhao, XiaoYun Li, Chan Zhang, JingYu Wang, JiLing Li, WeiDong Wang, ChuanLiang Quan, Wei Liu, XiaoJun Shu, Zheng Liu, Mingqing Chen, Jing Institute of Theoretical Physics Department of Physics State Key Laboratory of Quantum Optics and Quantum Optics Devices Collaborative Innovation Center of Extreme Optics Shanxi University Taiyuan030006 China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Center for Cold Atom Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan430071 China Institute of Applied Physics and Computational Mathematics P.O. Box 8009 Beijing100088 China Center for Advanced Material Diagnostic Technology Shenzhen Technology University Shenzhen518118 China School of Physics and Electrical Engineering Kashgar University Kashgar844006 China

The deconvolution procedure of the laser-induced ultrafast imaging schemes is usually based on strong field approximation (SFA) wherein the Coulomb interaction between the parent ion and the freed electron is ignored after ionization. In the laser-induced electron diffraction (LIED) approach, for example, the high energy part of the above-threshold ionization (ATI) spectrum used for analysis is assumed to be produced mostly by the 1st-return-recollision trajectories according to the SFA. By performing a joint theoretical and experimental investigation on the ATI spectrum, the dominant role of the 3rd-return-recollision trajectories in the high energy part of the spectrum due to the ionic Coulomb field is identified, which invalidates the key assumption adopted in the conventional LIED approach. Since the incident (return) electron beams produced by the 1st and 3rd returns possess distinct characteristics of beam energy, beam diameter and temporal evolution law due to the influence of Coulomb field, the extracted results in the LIED will be significantly altered. Such Coulomb field effect should be taken into account in all kinds of laser-induced imaging schemes based on recollision. Copyright © 2019, The Authors. All rights reserved.

关键词： Ionization

来源：评论

学校读者我要写书评

暂无评论

The Evolution of Imperative programming Paradigms as a Search for New Ways to Reduce Code Duplication

引用

IOP Conference Series: Materials Science and Engineering 2020年第1期714卷

作者： T Avacheva A Prutzkow Department of Mathematics Physics and Medical Computer Sciences Ryazan State Medical University named after I. P. Pavlov Ryazan Russian Federation Department of Computational and Applied Mathematics Ryazan State Radio Engineering University named after V. F. Utkin Ryazan Russian Federation

The cause for imperative programming paradigm shift is the impossibility of developing software systems of a new level of complexity. We consider the evolution of programming paradigms: structured, procedural, and object-oriented. We demonstrate new ways of code duplication reducing have appeared with the shift of paradigm. We conclude the factor of code duplication reducing determines the direction of programming paradigm evolution. We discover the constraints, which were introduced in the paradigms, simplify the development of software systems. We conclude the new constraints allow the development of more complex software systems. The main reason for the code duplication is the low qualification of programmers. Therefore, in the process of learning programming, one should pay attention to code duplication and ways to reduce it.

关键词：

来源：评论

学校读者我要写书评

暂无评论

On Partial Regularity of Suitable Weak Solutions to the Stationary Fractional Navier-Stokes Equations in Dimension Four and Five

引用

Acta Mathematica Sinica,English Series 2017年第12期33卷 1632-1646页

作者： Xiao Li GUO Yue Yang MEN Department of Mathematics and Information Science Zhengzhou University of Light Industry Zhengzhou 450002 P. R. China Institute of Applied Physics and Computational Mathematics Beijing 100088 P. R. China

In this paper, we investigate the partial regularity of suitable weak solutions to the multi- dimensional stationary Navier-Stokes equations with fractional power of the Laplacian （-△）^α （n/6 ≤α〈1 and a ≠ 1/2）. It is shown that the n ＋ 2 - 6α （3 ≤ n ≤5） dimensional Hausdorff measure of the set of the possible singular points of suitable weak solutions to the system is zero, which extends a recent result of Tang and Yu [19] to four and five dimension. Moreover, the pressure in ε-regularity criteria is an improvement of corresponding results in [1, 13, 18, 20].

关键词： Stationary Navier-Stokes equations suitable weak solutions partial regularity

来源：评论

学校读者我要写书评

暂无评论

Doping-induced antiferromagnetic bicollinear insulating state and superconducting temperature of monolayer FeSe systems

引用

Physical Review B 2018年第1期98卷 014504-014504页

作者： Michael C. Lucking Fawei Zheng Myung Joon Han Junhyeok Bang Shengbai Zhang Department of Physics Applied Physics and Astronomy Rensselaer Polytechnic Institute Troy New York 12180 USA Institute of Applied Physics and Computational Mathematics Beijing 100088 China Department of Physics Korea Advanced Institute of Science and Technology (KAIST) Daejeon 305-701 Korea Spin Engineering Physics Team Korea Basic Science Institute (KBSI) Daejeon 305-806 Korea

First-principles calculations of ionic-liquid-gated (Li,Fe)OHFeSe suggest a metal-insulator transition at a nominal Li/Fe ratio of 75/25 in the (Li,Fe)OH layer. While doping increases Fermi energy, the formation of an antiferromagnetic bicollinear phase is the key for the transition. It is expected that this insulating phase also exists in other FeSe systems upon heavy electron doping, and its presence can hinder the increase of superconducting temperature. These results offer clues on how to optimize superconductivity amid its interplay with magnetic properties in FeSe systems.

关键词： Electronic structure High-temperature superconductors Monolayer films Pnictides Density functional theory

来源：评论

学校读者我要写书评

暂无评论

First Sagittarius A* Event Horizon Telescope Results. VI: Testing the Black Hole Metricc

arXiv

引用

arXiv 2023年

作者： Akiyama, Kazunori Alberdi, Antxon Alef, Walter Algaba, Juan Carlos Anantua, Richard Asada, Keiichi Azulay, Rebecca Bach, Uwe Baczko, Anne-Kathrin Ball, David Baloković, Mislav Barrett, John Bauböck, Michi Benson, Bradford A. Bintley, Dan Blackburn, Lindy Blundell, Raymond Bouman, Katherine L. Bower, Geoffrey C. Boyce, Hope Bremer, Michael Brinkerink, Christiaan D. Brissenden, Roger Britzen, Silke Broderick, Avery E. Broguiere, Dominique Bronzwaer, Thomas Bustamante, Sandra Byun, Do-Young Carlstrom, John E. Ceccobello, Chiara Chael, Andrew Chan, Chi-Kwan Chatterjee, Koushik Chatterjee, Shami Chen, Ming-Tang Chen, Yongjun Cheng, Xiaopeng Cho, Ilje Christian, Pierre Conroy, Nicholas S. Conway, John E. Cordes, James M. Crawford, Thomas M. Crew, Geoffrey B. Cruz-Osorio, Alejandro Cui, Yuzhu Davelaar, Jordy De Laurentis, Mariafelicia Deane, Roger Dempsey, Jessica Desvignes, Gregory Dexter, Jason Dhruv, Vedant Doeleman, Sheperd S. Dougal, Sean Dzib, Sergio A. Eatough, Ralph P. Emami, Razieh Falcke, Heino Farah, Joseph Fish, Vincent L. Fomalont, Ed Ford, H. Alyson Fraga-Encinas, Raquel Freeman, William T. Friberg, Per Fromm, Christian M. Fuentes, Antonio Galison, Peter Gammie, Charles F. García, Roberto Gentaz, Olivier Georgiev, Boris Goddi, Ciriaco Gold, Roman Gómez-Ruiz, Arturo I. Gómez, José L. Gu, Minfeng Gurwell, Mark Hada, Kazuhiro Haggard, Daryl Haworth, Kari Hecht, Michael H. Hesper, Ronald Heumann, Dirk Ho, Luis C. Ho, Paul Honma, Mareki Huang, Chih-Wei L. Huang, Lei Hughes, David H. Ikeda, Shiro Impellizzeri, C.M. Violette Inoue, Makoto Issaoun, Sara James, David J. Jannuzi, Buell T. Janssen, Michael Jeter, Britton Jiang, Wu Jiménez-Rosales, Alejandra Johnson, Michael D. Jorstad, Svetlana Joshi, Abhishek V. Jung, Taehyun Karami, Mansour Karuppusamy, Ramesh Kawashima, Tomohisa Keating, Garrett K. Kettenis, Mark Kim, Dong-Jin Kim, Jae-Young Kim, Jongsoo Kim, Junhan Kino, Motoki Koay, Jun Yi Kocherlakota, Prashant Kofuji, Yutaro Koch, Patrick M. Koyama, Shoko Kramer, Carsten Kramer, Michael Krichbaum, Thomas P. Ku Massachusetts Institute of Technology Haystack Observatory 99 Millstone Road WestfordMA01886 United States National Astronomical Observatory of Japan 2-21-1 Osawa Mitaka Tokyo181-8588 Japan Black Hole Initiative at Harvard University 20 Garden Street CambridgeMA02138 United States Instituto de Astrofísica de Andalucía-CSIC Glorieta de la Astronomía s/n GranadaE-18008 Spain Max-Planck-Institut für Radioastronomie Auf dem Hügel 69 BonnD-53121 Germany Department of Physics Faculty of Science Universiti Malaya Kuala Lumpur50603 Malaysia Center for Astrophysics Harvard & Smithsonian 60 Garden Street CambridgeMA02138 United States Department of Physics & Astronomy The University of Texas at San Antonio One UTSA Circle San AntonioTX78249 United States Institute of Astronomy and Astrophysics Academia Sinica 11F of Astronomy-Mathematics Building AS/NTU No. 1 Sec. 4 Roosevelt Rd Taipei10617 Taiwan Departament d’Astronomia i Astrofísica Universitat de València C. Dr. Moliner 50 Burjassot ValènciaE-46100 Spain Observatori Astronòmic Universitat de València C. Catedrático José Beltrán 2 València PaternaE-46980 Spain Steward Observatory Department of Astronomy University of Arizona 933 N. Cherry Ave. TucsonAZ85721 United States Yale Center for Astronomy & Astrophysics Yale University 52 Hillhouse Avenue New HavenCT06511 United States Department of Physics University of Illinois 1110 West Green Street UrbanaIL61801 United States Fermi National Accelerator Laboratory MS209 P.O. Box 500 BataviaIL60510 United States Department of Astronomy and Astrophysics University of Chicago 5640 South Ellis Avenue ChicagoIL60637 United States East Asian Observatory 660 N. A’ohoku Place HiloHI96720 United States 660 N. A’ohoku Place HiloHI96720 United States California Institute of Technology 1200 East California Boulevard PasadenaCA91125 United States Institute of Astronomy and Astrophysics Academia Sinica 645 N. A’ohoku Place HiloHI

Astrophysical black holes are expected to be described by the Kerr metric. This is the only stationary, vacuum, axisymmetric metric, without electromagnetic charge, that satisfies Einstein’s equations and does not have pathologies outside of the event horizon. We present new constraints on potential deviations from the Kerr prediction based on 2017 EHT observations of Sagittarius A∗ (Sgr A∗). We calibrate the relationship between the geometrically defined black hole shadow and the observed size of the ring-like images using a library that includes both Kerr and non-Kerr simulations. We use the exquisite prior constraints on the mass-to-distance ratio for Sgr A∗ to show that the observed image size is within ∼ 10% of the Kerr predictions. We use these bounds to constrain metrics that are parametrically different from Kerr as well as the charges of several known spacetimes. To consider alternatives to the presence of an event horizon we explore the possibility that Sgr A∗ is a compact object with a surface that either absorbs and thermally re-emits incident radiation or partially reflects it. Using the observed image size and the broadband spectrum of Sgr A∗, we conclude that a thermal surface can be ruled out and a fully reflective one is unlikely. We compare our results to the broader landscape of gravitational tests. Together with the bounds found for stellar mass black holes and the M87 black hole, our observations provide further support that the external spacetimes of all black holes are described by the Kerr metric, independent of their mass. © 2023, CC BY.

关键词： Black holes

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：