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Author Correction: Open-access quantitative MRI data of the spinal cord and reproducibility across participants, sites and manufacturers

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Scientific data 2021年第1期8卷 242页

作者： Julien Cohen-Adad Eva Alonso-Ortiz Mihael Abramovic Carina Arneitz Nicole Atcheson Laura Barlow Robert L Barry Markus Barth Marco Battiston Christian Büchel Matthew Budde Virginie Callot Anna J E Combes Benjamin De Leener Maxime Descoteaux Paulo Loureiro de Sousa Marek Dostál Julien Doyon Adam Dvorak Falk Eippert Karla R Epperson Kevin S Epperson Patrick Freund Jürgen Finsterbusch Alexandru Foias Michela Fratini Issei Fukunaga Claudia A M Gandini Wheeler-Kingshott Giancarlo Germani Guillaume Gilbert Federico Giove Charley Gros Francesco Grussu Akifumi Hagiwara Pierre-Gilles Henry Tomáš Horák Masaaki Hori James Joers Kouhei Kamiya Haleh Karbasforoushan Miloš Keřkovský Ali Khatibi Joo-Won Kim Nawal Kinany Hagen H Kitzler Shannon Kolind Yazhuo Kong Petr Kudlička Paul Kuntke Nyoman D Kurniawan Slawomir Kusmia René Labounek Maria Marcella Laganà Cornelia Laule Christine S Law Christophe Lenglet Tobias Leutritz Yaou Liu Sara Llufriu Sean Mackey Eloy Martinez-Heras Loan Mattera Igor Nestrasil Kristin P O'Grady Nico Papinutto Daniel Papp Deborah Pareto Todd B Parrish Anna Pichiecchio Ferran Prados Àlex Rovira Marc J Ruitenberg Rebecca S Samson Giovanni Savini Maryam Seif Alan C Seifert Alex K Smith Seth A Smith Zachary A Smith Elisabeth Solana Y Suzuki George Tackley Alexandra Tinnermann Jan Valošek Dimitri Van De Ville Marios C Yiannakas Kenneth A Weber Ii Nikolaus Weiskopf Richard G Wise Patrik O Wyss Junqian Xu NeuroPoly Lab Institute of Biomedical Engineering Polytechnique Montreal Montreal QC Canada. jcohen@polymtl.ca. Functional Neuroimaging Unit CRIUGM Université de Montréal Montreal QC Canada. jcohen@polymtl.ca. Mila - Quebec AI Institute Montreal QC Canada. jcohen@polymtl.ca. NeuroPoly Lab Institute of Biomedical Engineering Polytechnique Montreal Montreal QC Canada. Department of Radiology Swiss Paraplegic Centre Nottwil Switzerland. Centre for Advanced Imaging The University of Queensland Brisbane Australia. Department of Radiology University of British Columbia Vancouver BC Canada. Athinoula A. Martinos Center for Biomedical Imaging Department of Radiology Massachusetts General Hospital Charlestown MA USA. Department of Radiology Harvard Medical School Boston MA USA. Harvard-Massachusetts Institute of Technology Health Sciences & Technology Cambridge MA USA. School of Information Technology and Electrical Engineering The University of Queensland Brisbane Australia. NMR Research Unit Queen Square MS Centre UCL Queen Square Institute of Neurology Faculty of Brain Sciences University College London London UK. Department of Systems Neuroscience University Medical Center Hamburg-Eppendorf Hamburg Germany. Department of Neurosurgery Medical College of Wisconsin Milwaukee WI USA. Aix-Marseille Univ CNRS CRMBM Marseille France. APHM Hopital Universitaire Timone CEMEREM Marseille France. Vanderbilt University Institute of Imaging Science Vanderbilt University Medical Center Nashville TN USA. Department of Computer and Software Engineering Polytechnique Montreal Montreal Canada. CHU Sainte-Justine Research Centre Montreal QC Canada. Centre de Recherche CHUS CIMS Sherbrooke Canada. Sherbrooke Connectivity Imaging Lab (SCIL) Computer Science department Université de Sherbrooke Sherbrooke Canada. Université de Strasbourg CNRS ICube Strasbourg France. UHB - University Hospital Brno and Masaryk University Department of Radiology and Nuclear

Fake news propagate differently from real news even at early stages of spreading

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arXiv 2018年

作者： Zhao, Zilong Zhao, Jichang Sano, Yukie Levy, Orr Takayasu, Hideki Takayasu, Misako Li, Daqing Wu, Junjie Havlin, Shlomo School of Reliability and Systems Engineering Beihang University Beijing100191 China Science and Technology on Reliability and Environmental Engineering Laboratory Beijing100191 China School of Economics and Management Beihang University Beijing100191 China Faculty of Engineering Information and Systems University of Tsukuba Tennodai Tsukuba Ibaraki305-8573 Japan Department of Physics Bar-Ilan University Ramat Gan5290002 Israel Sony Computer Science Laboratories 3-14-13 Higashi-Gotanda Tokyo141-0022 Japan Institute of Innovative Research Tokyo Institute of Technology Yokohama226-8502 Japan Beijing Advanced Innovation Center for Big Data and Brain Computing Beihang University Beijing100191 China

Social media can be a double-edged sword for society, either as a convenient channel exchanging ideas or as an unexpected conduit circulating fake news through a large population. While existing studies of fake news focus on theoretical modeling of propagation or identification methods based on machine learning, it is important to understand the realistic mechanisms between theoretical models and black-box methods. Here we track large databases of fake news and real news in both, Weibo in China and Twitter in Japan from different culture, which include their complete traces of re-postings. We find in both online social networks that fake news spreads distinctively from real news even at early stages of propagation, e.g. five hours after the first re-postings. Our finding demonstrates collective structural signals that help to understand the different propagation evolution of fake news and real news. Different from earlier studies, identifying the topological properties of the information propagation at early stages may offer novel features for early detection of fake news in social media. Copyright © 2018, The Authors. All rights reserved.

关键词： Social networking (online)

On the CNOT-complexity of CNOT-phase circuits

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arXiv 2017年

作者： Amy, Matthew Azimzadeh, Parsiad Mosca, Michele Institute for Quantum Computing University of Waterloo Canada David R. Cheriton School of Computer Science University of Waterloo Canada Department of Combinatorics & Optimization University of Waterloo Canada Perimeter Institute for Theoretical Physics Waterloo Canada Canadian Institute for Advanced Research Toronto Canada

We study the problem of CNOT-optimal quantum circuit synthesis over gate sets consisting of CNOT and Z-basis rotations of arbitrary angles. We show that the circuit-polynomial correspondence relates such circuits to Fourier expansions of pseudo-Boolean functions, and that for certain classes of functions this expansion uniquely determines the minimum CNOT cost of an implementation. As a corollary we prove that CNOT minimization over CNOT and phase gates is at least as hard as synthesizing a CNOT-optimal circuit computing a set of parities of its inputs. We then show that this problem is NP-complete for two restricted cases where all CNOT gates are required to have the same target, and where the circuit inputs are encoded in a larger state space. The latter case has applications to CNOT optimization over more general Clifford+T circuits. We further present an efficient heuristic algorithm for synthesizing circuits over CNOT and Z-basis rotations with small CNOT cost. Our experiments show a 23% reduction of CNOT gates on average across a suite of Clifford+T benchmark circuits, with a maximum reduction of 43%. Copyright © 2017, The Authors. All rights reserved.

关键词： Timing circuits

Dimensionality-driven orthorhombic MoTe2 at room temperature

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Physical Review B 2018年第4期97卷 041410(R)-041410(R)页

作者： Rui He Shazhou Zhong Hyun Ho Kim Gaihua Ye Zhipeng Ye Logan Winford Daniel McHaffie Ivana Rilak Fangchu Chen Xuan Luo Yuping Sun Adam W. Tsen Department of Electrical and Computer Engineering Texas Tech University Lubbock Texas 79409 USA Department of Physics University of Northern Iowa Cedar Falls Iowa 50614 USA Institute for Quantum Computing University of Waterloo Waterloo Ontario Canada N2L 3G1 Department of Physics and Astronomy University of Waterloo Waterloo Ontario Canada N2L 3G1 Department of Chemistry University of Waterloo Waterloo Ontario Canada N2L 3G1 Key Laboratory of Materials Physics Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 People's Republic of China University of Science and Technology of China Hefei 230026 China High Magnetic Field Laboratory Chinese Academy of Sciences Hefei 230031 People's Republic of China Collaborative Innovation Centre of Advanced Microstructures Nanjing University Nanjing 210093 People's Republic of China

We use a combination of Raman spectroscopy and transport measurements to study thin flakes of the type-II Weyl semimetal candidate MoTe2 protected from oxidation. In contrast to bulk crystals, which undergo a phase transition from monoclinic to the inversion symmetry breaking, orthorhombic phase below ∼250K, we find that in moderately thin samples below ∼12nm, a single orthorhombic phase exists up to and beyond room temperature. This could be due to the effect of c-axis confinement, which lowers the energy of an out-of-plane hole band and stabilizes the orthorhombic structure. Our results suggest that Weyl nodes, predicated upon inversion symmetry breaking, may be observed in thin MoTe2 at room temperature.

关键词： Phase transitions Structural properties Topological materials Transition metal dichalcogenides Weyl semimetal Raman spectroscopy

Eavesdropping and countermeasures for backflash side channel in quantum cryptography

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arXiv 2018年

作者： Pinheiro, Paulo Vinicius Pereira Chaiwongkhot, Poompong Sajeed, Shihan Horn, Rolf T. Bourgoin, Jean-Philippe Jennewein, Thomas Lütkenhaus, Norbert Makarov, Vadim Engineering Department Paraíso Faculty of Ceará Juazeiro do Norte Ceará63010-465 Brazil Department of Teleinformatic Engineering Federal University of Ceará C.P.6007 Campus do Pici Fortaleza Brazil Institute for Quantum Computing University of Waterloo WaterlooONN2L 3G1 Canada Department of Physics and Astronomy University of Waterloo WaterlooONN2L 3G1 Canada Department of Electrical and Computer Engineering University of Toronto M5S 3G4 Canada Department of Electrical and Computer Engineering University of Waterloo WaterlooONN2L 3G1 Canada Quantum Information Science Program Canadian Institute for Advanced Research TorontoON Canada Russian Quantum Center MISIS University Moscow Russia

Quantum key distribution (QKD) promises information theoretic secure key as long as the device performs as assumed in the theoretical model. One of the assumptions is an absence of information leakage about individual photon detection outcomes of the receiver unit. Here we investigate the information leakage from a QKD receiver due to photon emission caused by detection events in single-photon detectors (backflash). We test commercial silicon avalanche photodiodes and a photomultiplier tube, and find that the former emit backflashes. We study the spectral, timing and polarization characteristics of these backflash photons. We experimentally demonstrate on a free-space QKD receiver that an eavesdropper can distinguish which detector has clicked inside it, and thus acquire secret information. A set of countermeasures both in theory and on the physical devices are discussed. Copyright © 2018, The Authors. All rights reserved.

关键词： Quantum cryptography

Quantum Chemistry in the Age of Quantum computing

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arXiv 2018年

作者： Cao, Yudong Romero, Jonathan Olson, Jonathan P. Degroote, Matthias Johnson, Peter D. Kieferová, Mária Kivlichan, Ian D. Menke, Tim Peropadre, Borja Sawaya, Nicolas P.D. Sim, Sukin Veis, Libor Aspuru-Guzik, Alán Department of Chemistry and Chemical Biology Harvard University CambridgeMA02138 United States Zapata Computing Inc. CambridgeMA02139 United States Department of Chemistry University of Toronto TorontoONM5G 1Z8 Canada Department of Computer Science University of Toronto TorontoONM5G 1Z8 Canada Department of Physics and Astronomy Macquarie University SydneyNSW2109 Australia Institute for Quantum Computing Department of Physics and Astronomy University of Waterloo WaterlooONN2L 3G1 Canada Department of Physics Harvard University CambridgeMA02138 United States Research Laboratory of Electronics Massachusetts Institute of Technology CambridgeMA02139 United States Department of Physics Massachusetts Institute of Technology CambridgeMA02139 United States Intel Labs Intel Corporation Santa ClaraCA95054 United States J. Heyrovský Institute of Physical Chemistry Academy of Sciences of the Czech Republic v.v.i. Dolejškova 3 Prague 818223 Czech Republic Canadian Institute for Advanced Research TorontoONM5G 1Z8 Canada Vector Institute for Artificial Intelligence TorontoONM5S 1M1 Canada

Practical challenges in simulating quantum systems on classical computers have been widely recognized in the quantum physics and quantum chemistry communities over the past century. Although many approximation methods have been introduced, the complexity of quantum mechanics remains hard to appease. The advent of quantum computation brings new pathways to navigate this challenging complexity landscape. By manipulating quantum states of matter and taking advantage of their unique features such as superposition and entanglement, quantum computers promise to efficiently deliver accurate results for many important problems in quantum chemistry such as the electronic structure of molecules. In the past two decades significant advances have been made in developing algorithms and physical hardware for quantum computing, heralding a revolution in simulation of quantum systems. This article is an overview of the algorithms and results that are relevant for quantum chemistry. The intended audience is both quantum chemists who seek to learn more about quantum computing, and quantum computing researchers who would like to explore applications in quantum chemistry. Copyright © 2018, The Authors. All rights reserved.

关键词： Quantum optics

Comparison of Fragmentation Functions for Jets Dominated by Light Quarks and Gluons from pp and Pb+Pb Collisions in ATLAS

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Physical Review Letters 2019年第4期123卷 042001-042001页

作者： M. Aaboud G. Aad B. Abbott O. Abdinov B. Abeloos D. K. Abhayasinghe S. H. Abidi O. S. AbouZeid N. L. Abraham H. Abramowicz H. Abreu Y. Abulaiti B. S. Acharya S. Adachi L. Adamczyk J. Adelman M. Adersberger A. Adiguzel T. Adye A. A. Affolder Y. Afik C. Agheorghiesei J. A. Aguilar-Saavedra F. Ahmadov G. Aielli S. Akatsuka T. P. A. Åkesson E. Akilli A. V. Akimov G. L. Alberghi J. Albert P. Albicocco M. J. Alconada Verzini S. Alderweireldt M. Aleksa I. N. Aleksandrov C. Alexa T. Alexopoulos M. Alhroob B. Ali G. Alimonti J. Alison S. P. Alkire C. Allaire B. M. M. Allbrooke B. W. Allen P. P. Allport A. Aloisio A. Alonso F. Alonso C. Alpigiani A. A. Alshehri M. I. Alstaty B. Alvarez Gonzalez D. Álvarez Piqueras M. G. Alviggi B. T. Amadio Y. Amaral Coutinho L. Ambroz C. Amelung D. Amidei S. P. Amor Dos Santos S. Amoroso C. S. Amrouche C. Anastopoulos L. S. Ancu N. Andari T. Andeen C. F. Anders J. K. Anders K. J. Anderson A. Andreazza V. Andrei C. R. Anelli S. Angelidakis I. Angelozzi A. Angerami A. V. Anisenkov A. Annovi C. Antel M. T. Anthony M. Antonelli D. J. A. Antrim F. Anulli M. Aoki J. A. Aparisi Pozo L. Aperio Bella G. Arabidze J. P. Araque V. Araujo Ferraz R. Araujo Pereira A. T. H. Arce R. E. Ardell F. A. Arduh J-F. Arguin S. Argyropoulos A. J. Armbruster L. J. Armitage A. Armstrong O. Arnaez H. Arnold M. Arratia O. Arslan A. Artamonov G. Artoni S. Artz S. Asai N. Asbah A. Ashkenazi E. M. Asimakopoulou L. Asquith K. Assamagan R. Astalos R. J. Atkin M. Atkinson N. B. Atlay K. Augsten G. Avolio R. Avramidou M. K. Ayoub G. Azuelos A. E. Baas M. J. Baca H. Bachacou K. Bachas M. Backes P. Bagnaia M. Bahmani H. Bahrasemani A. J. Bailey J. T. Baines M. Bajic C. Bakalis O. K. Baker P. J. Bakker D. Bakshi Gupta E. M. Baldin P. Balek F. Balli W. K. Balunas J. Balz E. Banas A. Bandyopadhyay S. Banerjee A. A. E. Bannoura L. Barak W. M. Barbe E. L. Barberio D. Barberis M. Barbero T. Barillari M-S. Barisits J. Barkeloo T. Barklow N. Barlow R. Barnea S. L. Barnes B. M. Barnett R. M. Barnett Z. Barnovska-Blenessy A. Baroncelli Faculté des Sciences Université Mohamed Premier and LPTPM Oujda Morocco CPPM Aix-Marseille Université CNRS/IN2P3 Marseille France Homer L. Dodge Department of Physics and Astronomy University of Oklahoma Norman Oklahoma USA Institute of Physics Azerbaijan Academy of Sciences Baku Azerbaijan LAL Université Paris-Sud CNRS/IN2P3 Université Paris-Saclay Orsay France Department of Physics Royal Holloway University of London Egham United Kingdom Department of Physics University of Toronto Toronto Ontario Canada Niels Bohr Institute University of Copenhagen Copenhagen Denmark Department of Physics and Astronomy University of Sussex Brighton United Kingdom Raymond and Beverly Sackler School of Physics and Astronomy Tel Aviv University Tel Aviv Israel Department of Physics Technion Israel Institute of Technology Haifa Israel High Energy Physics Division Argonne National Laboratory Argonne Illinois USA INFN Gruppo Collegato di Udine Sezione di Trieste Udine Italy ICTP Trieste Italy International Center for Elementary Particle Physics and Department of Physics University of Tokyo Tokyo Japan AGH University of Science and Technology Faculty of Physics and Applied Computer Science Krakow Poland Department of Physics Northern Illinois University DeKalb Illinois USA Fakultät für Physik Ludwig-Maximilians-Universität München München Germany Department of Physics Bogazici University Istanbul Turkey Particle Physics Department Rutherford Appleton Laboratory Didcot United Kingdom Santa Cruz Institute for Particle Physics University of California Santa Cruz Santa Cruz California USA Department of Physics Alexandru Ioan Cuza University of Iasi Iasi Romania Universidad de Granada Granada (Spain) Spain Laboratório de Instrumentação e Física Experimental de Partículas—LIP Portugal Joint Institute for Nuclear Research Dubna Russia INFN Sezione di Roma Tor Vergata Italy Dipartimento di Fisica Università di Roma Tor Vergata Roma Italy Faculty of Science Kyo

Charged-particle fragmentation functions for jets azimuthally balanced by a high-transverse-momentum, prompt, isolated photon are measured in 25 pb−1 of pp and 0.49 nb−1 of Pb+Pb collision data at 5.02 TeV per nucleon pair recorded with the ATLAS detector at the Large Hadron Collider. The measurements are compared to predictions of Monte Carlo generators and to measurements of inclusively selected jets. In pp collisions, a different jet fragmentation function in photon-tagged events from that in inclusive jet events arises from the difference in fragmentation between light quarks and gluons. The ratios of the fragmentation functions in Pb+Pb events to that in pp events are used to explore the parton color-charge dependence of jet quenching in the hot medium. In relatively peripheral collisions, fragmentation functions exhibit a similar modification pattern for photon-tagged and inclusive jets. However, photon-tagged jets are observed to have larger modifications than inclusive jets in central Pb+Pb events.

关键词： Quantum chromodynamics Quark & gluon jets Quark-gluon plasma Relativistic heavy-ion collisions Strong interaction

Observation of Light-by-Light Scattering in Ultraperipheral Pb+Pb Collisions with the ATLAS Detector

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Physical Review Letters 2019年第5期123卷 052001-052001页

作者： G. Aad B. Abbott D. C. Abbott O. Abdinov A. Abed Abud K. Abeling D. K. Abhayasinghe S. H. Abidi O. S. AbouZeid N. L. Abraham H. Abramowicz H. Abreu Y. Abulaiti B. S. Acharya B. Achkar S. Adachi L. Adam C. Adam Bourdarios L. Adamczyk L. Adamek J. Adelman M. Adersberger A. Adiguzel S. Adorni T. Adye A. A. Affolder Y. Afik C. Agapopoulou M. N. Agaras A. Aggarwal C. Agheorghiesei J. A. Aguilar-Saavedra F. Ahmadov W. S. Ahmed X. Ai G. Aielli S. Akatsuka T. P. A. Åkesson E. Akilli A. V. Akimov K. Al Khoury G. L. Alberghi J. Albert M. J. Alconada Verzini S. Alderweireldt M. Aleksa I. N. Aleksandrov C. Alexa D. Alexandre T. Alexopoulos A. Alfonsi M. Alhroob B. Ali G. Alimonti J. Alison S. P. Alkire C. Allaire B. M. M. Allbrooke B. W. Allen P. P. Allport A. Aloisio A. Alonso F. Alonso C. Alpigiani A. A. Alshehri M. Alvarez Estevez D. Álvarez Piqueras M. G. Alviggi Y. Amaral Coutinho A. Ambler L. Ambroz C. Amelung D. Amidei S. P. Amor Dos Santos S. Amoroso C. S. Amrouche F. An C. Anastopoulos N. Andari T. Andeen C. F. Anders J. K. Anders A. Andreazza V. Andrei C. R. Anelli S. Angelidakis A. Angerami A. V. Anisenkov A. Annovi C. Antel M. T. Anthony M. Antonelli D. J. A. Antrim F. Anulli M. Aoki J. A. Aparisi Pozo L. Aperio Bella G. Arabidze J. P. Araque V. Araujo Ferraz R. Araujo Pereira C. Arcangeletti A. T. H. Arce F. A. Arduh J-F. Arguin S. Argyropoulos J.-H. Arling A. J. Armbruster L. J. Armitage A. Armstrong O. Arnaez H. Arnold A. Artamonov G. Artoni S. Artz S. Asai N. Asbah E. M. Asimakopoulou L. Asquith K. Assamagan R. Astalos R. J. Atkin M. Atkinson N. B. Atlay H. Atmani K. Augsten G. Avolio R. Avramidou M. K. Ayoub A. M. Azoulay G. Azuelos M. J. Baca H. Bachacou K. Bachas M. Backes F. Backman P. Bagnaia M. Bahmani H. Bahrasemani A. J. Bailey V. R. Bailey J. T. Baines M. Bajic C. Bakalis O. K. Baker P. J. Bakker D. Bakshi Gupta S. Balaji E. M. Baldin P. Balek F. Balli W. K. Balunas J. Balz E. Banas A. Bandyopadhyay Sw. Banerjee A. A. E. Bannoura L. Barak W. M. Barbe E. L. Barberio D. Barberis M. Barbero T. Barillari CPPM Aix-Marseille Université CNRS/IN2P3 Marseille France Homer L. Dodge Department of Physics and Astronomy University of Oklahoma Norman Oklahoma USA Department of Physics University of Massachusetts Amherst Massachusetts USA Institute of Physics Azerbaijan Academy of Sciences Baku Azerbaijan INFN Sezione di Pavia Italy Dipartimento di Fisica Università di Pavia Pavia Italy II. Physikalisches Institut Georg-August-Universität Göttingen Göttingen Germany Department of Physics Royal Holloway University of London Egham United Kingdom Department of Physics University of Toronto Toronto Ontario Canada Niels Bohr Institute University of Copenhagen Copenhagen Denmark Department of Physics and Astronomy University of Sussex Brighton United Kingdom Raymond and Beverly Sackler School of Physics and Astronomy Tel Aviv University Tel Aviv Israel Department of Physics Technion Israel Institute of Technology Haifa Israel High Energy Physics Division Argonne National Laboratory Argonne Illinois USA INFN Gruppo Collegato di Udine Sezione di Trieste Udine Italy ICTP Trieste Italy International Center for Elementary Particle Physics and Department of Physics University of Tokyo Tokyo Japan Institut für Physik Universität Mainz Mainz Germany LAL Université Paris-Sud CNRS/IN2P3 Université Paris-Saclay Orsay France AGH University of Science and Technology Faculty of Physics and Applied Computer Science Krakow Poland Department of Physics Northern Illinois University DeKalb Illinois USA Fakultät für Physik Ludwig-Maximilians-Universität München München Germany Department of Physics Bogazici University Istanbul Turkey Département de Physique Nucléaire et Corpusculaire Université de Genève Genève Switzerland Particle Physics Department Rutherford Appleton Laboratory Didcot United Kingdom Santa Cruz Institute for Particle Physics University of California Santa Cruz Santa Cruz California USA LPC Université Clermont Auvergne CNRS/IN2P3 Clermont-Ferran

This Letter describes the observation of the light-by-light scattering process, γγ→γγ, in Pb+Pb collisions at sNN=5.02 TeV. The analysis is conducted using a data sample corresponding to an integrated luminosity of 1.73 nb−1, collected in November 2018 by the ATLAS experiment at the LHC. Light-by-light scattering candidates are selected in events with two photons produced exclusively, each with transverse energy ETγ>3 GeV and pseudorapidity |ηγ|<2.4, diphoton invariant mass above 6 GeV, and small diphoton transverse momentum and acoplanarity. After applying all selection criteria, 59 candidate events are observed for a background expectation of 12±3 events. The observed excess of events over the expected background has a significance of 8.2 standard deviations. The measured fiducial cross section is 78±13(stat)±7(syst)±3(lumi) nb.

关键词： Relativistic heavy-ion collisions

Combination of Searches for Invisible Higgs Boson Decays with the ATLAS Experiment

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Physical Review Letters 2019年第23期122卷 231801-231801页

作者： M. Aaboud G. Aad B. Abbott D. C. Abbott O. Abdinov A. Abed Abud D. K. Abhayasinghe S. H. Abidi O. S. AbouZeid N. L. Abraham H. Abramowicz H. Abreu Y. Abulaiti B. S. Acharya S. Adachi L. Adam C. Adam Bourdarios L. Adamczyk L. Adamek J. Adelman M. Adersberger A. Adiguzel S. Adorni T. Adye A. A. Affolder Y. Afik C. Agapopoulou M. N. Agaras A. Aggarwal C. Agheorghiesei J. A. Aguilar-Saavedra F. Ahmadov G. Aielli S. Akatsuka T. P. A. Åkesson E. Akilli A. V. Akimov K. Al Khoury G. L. Alberghi J. Albert M. J. Alconada Verzini S. Alderweireldt M. Aleksa I. N. Aleksandrov C. Alexa D. Alexandre T. Alexopoulos A. Alfonsi M. Alhroob B. Ali G. Alimonti J. Alison S. P. Alkire C. Allaire B. M. M. Allbrooke B. W. Allen P. P. Allport A. Aloisio A. Alonso F. Alonso C. Alpigiani A. A. Alshehri M. I. Alstaty M. Alvarez Estevez B. Alvarez Gonzalez D. Álvarez Piqueras M. G. Alviggi Y. Amaral Coutinho A. Ambler L. Ambroz C. Amelung D. Amidei S. P. Amor Dos Santos S. Amoroso C. S. Amrouche F. An C. Anastopoulos N. Andari T. Andeen C. F. Anders J. K. Anders A. Andreazza V. Andrei C. R. Anelli S. Angelidakis I. Angelozzi A. Angerami A. V. Anisenkov A. Annovi C. Antel M. T. Anthony M. Antonelli D. J. A. Antrim F. Anulli M. Aoki J. A. Aparisi Pozo L. Aperio Bella G. Arabidze J. P. Araque V. Araujo Ferraz R. Araujo Pereira A. T. H. Arce F. A. Arduh J-F. Arguin S. Argyropoulos J.-H. Arling A. J. Armbruster L. J. Armitage A. Armstrong O. Arnaez H. Arnold A. Artamonov G. Artoni S. Artz S. Asai N. Asbah E. M. Asimakopoulou L. Asquith K. Assamagan R. Astalos R. J. Atkin M. Atkinson N. B. Atlay H. Atmani K. Augsten G. Avolio R. Avramidou M. K. Ayoub A. M. Azoulay G. Azuelos A. E. Baas M. J. Baca H. Bachacou K. Bachas M. Backes F. Backman P. Bagnaia M. Bahmani H. Bahrasemani A. J. Bailey V. R. Bailey J. T. Baines M. Bajic C. Bakalis O. K. Baker P. J. Bakker D. Bakshi Gupta S. Balaji E. M. Baldin P. Balek F. Balli W. K. Balunas J. Balz E. Banas A. Bandyopadhyay Sw. Banerjee A. A. E. Bannoura L. Barak W. M. Barbe E. L. Barberio D. Barberis M. Barbero Faculté des Sciences Université Mohamed Premier and LPTPM Oujda Morocco CPPM Aix-Marseille Université CNRS/IN2P3 Marseille France Homer L. Dodge Department of Physics and Astronomy University of Oklahoma Norman Oklahoma USA Department of Physics University of Massachusetts Amherst Massachusetts USA Institute of Physics Azerbaijan Academy of Sciences Baku Azerbaijan INFN Sezione di Pavia Pavia Italy Dipartimento di Fisica Università di Pavia Pavia Italy Department of Physics Royal Holloway University of London Egham United Kingdom Department of Physics University of Toronto Toronto Ontario Canada Niels Bohr Institute University of Copenhagen Copenhagen Denmark Department of Physics and Astronomy University of Sussex Brighton United Kingdom Raymond and Beverly Sackler School of Physics and Astronomy Tel Aviv University Tel Aviv Israel Department of Physics Technion Israel Institute of Technology Haifa Israel High Energy Physics Division Argonne National Laboratory Argonne Illinois USA INFN Gruppo Collegato di Udine Sezione di Trieste Udine Italy ICTP Trieste Italy International Center for Elementary Particle Physics and Department of Physics University of Tokyo Tokyo Japan Institut für Physik Universität Mainz Mainz Germany LAL Université Paris-Sud CNRS/IN2P3 Université Paris-Saclay Orsay France AGH University of Science and Technology Faculty of Physics and Applied Computer Science Krakow Poland Department of Physics Northern Illinois University DeKalb Illinois USA Fakultät für Physik Ludwig-Maximilians-Universität München München Germany Department of Physics Bogazici University Istanbul Turkey Département de Physique Nucléaire et Corpusculaire Université de Genève Genève Switzerland Particle Physics Department Rutherford Appleton Laboratory Didcot United Kingdom Santa Cruz Institute for Particle Physics University of California Santa Cruz Santa Cruz California USA LPC Université Clermont Auvergne CNRS/IN2P3 Clermont-Ferrand

Dark matter particles, if sufficiently light, may be produced in decays of the Higgs boson. This Letter presents a statistical combination of searches for H→invisible decays where H is produced according to the standard model via vector boson fusion, Z(ℓℓ)H, and W/Z(had)H, all performed with the ATLAS detector using 36.1 fb−1 of pp collisions at a center-of-mass energy of s=13 TeV at the LHC. In combination with the results at s=7 and 8 TeV, an exclusion limit on the H→invisible branching ratio of 0.26(0.17−0.05+0.07) at 95% confidence level is observed (expected).

关键词： Extensions of Higgs sector Invisible decays Particle dark matter