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arXiv 2023年

作者： Conroy, Nicholas S. Bauböck, Michi Dhruv, Vedant Lee, Daeyoung Broderick, Avery E. Chan, Chi-Kwan Georgiev, Boris Joshi, Abhishek V. Prather, Ben Gammie, Charles F. Department of Astronomy University of Illinois at Urbana-Champaign 1002 West Green Street UrbanaIL61801 United States Department of Physics University of Illinois at Urbana-Champaign 1110 West Green Street UrbanaIL61801 United States Illinois Center for the Advanced Study of the Universe University of Illinois at Urbana-Champaign 1110 West Green St. UrbanaIL61801 United States Perimeter Institute for Theoretical Physics 31 Caroline Street North WaterlooONN2L 2Y5 Canada Department of Physics and Astronomy University of Waterloo 200 University Avenue West WaterlooONN2L 3G1 Canada Waterloo Centre for Astrophysics University of Waterloo WaterlooONN2L 3G1 Canada 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 Los Alamos National Lab Los AlamosNM87545 United States NCSA University of Illinois at Urbana-Champaign 1205 W. Clark St. UrbanaIL61801 United States

The Event Horizon Telescope (EHT) has produced images of M87* and Sagittarius A*, and will soon produce time sequences of images, or movies. In anticipation of this, we describe a technique to measure the rotation rate, or pattern speed Ωp, from movies using an autocorrelation technique. We validate the technique on Gaussian random field models with a known rotation rate and apply it to a library of synthetic images of Sgr A* based on general relativistic magnetohydrodynamics simulations. We predict that EHT movies will have Ωp ≈ 1◦ per GMc−3, which is of order 15% of the Keplerian orbital frequency in the emitting region. We can plausibly attribute the slow rotation seen in our models to the pattern speed of inward-propagating spiral shocks. We also find that Ωp depends strongly on inclination. Application of this technique will enable us to compare future EHT movies with the clockwise rotation of Sgr A* seen in near-infrared flares by GRAVITY. Pattern speed analysis of future EHT observations of M87* and Sgr A* may also provide novel constraints on black hole inclination and spin, as well as an independent measurement of black hole mass. © 2023, CC BY.

关键词： Black holes

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Prediction of the Binding Mechanism of a Selective DNA Methyltransferase 3A Inhibitor by Molecular Simulation

SSRN

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SSRN 2023年

作者： Kudo, Genki Hirao, Takumi Harada, Ryuhei Hirokawa, Takatsugu Shigeta, Yasuteru Yoshino, Ryunosuke Physics Department Graduate School of Pure and Applied Sciences University of Tsukuba 1-1-1 Tennodai Ibaraki Tsukuba305-8571 Japan Master’s Program in Medical Sciences Graduate School of Comprehensive Human Sciences University of Tsukuba Ibaraki Tsukuba305-8575 Japan Division of Biomedical Science Faculty of Medicine University of Tsukuba 1-1-1 Tennodai Ibaraki Tsukuba305-8575 Japan Center for Computational Sciences University of Tsukuba 1-1-1 Tennodai Ibaraki Tsukuba305-8577 Japan Transborder Medical Research Center University of Tsukuba 1-1-1 Tennodai Ibaraki Tsukuba305-8575 Japan Japan

DNA methylation is an epigenetic mechanism that introduces a methyl group at the C5 position of cytosine. This reaction is catalyzed by DNA methyltransferases (DNMTs) and is essential for the regulation of gene transcription. The DNMT1 and DNMT3A or -3B family proteins are known targets for the inhibition of DNA hypermethylation in cancer cells. A selective non-nucleoside DNMT3A inhibitor that mimics S-adenosyl-l-methionine and deoxycytidine has been developed;however, its selectivity mechanism is unclear because the structure of the inhibitor–protein complex has not yet been determined. Therefore, we performed docking and molecular dynamics simulations to predict the structure of the complex formed by the association between DNMT3A and the selective inhibitor. Through our simulations, binding free energy decomposition analysis, structural isoform comparison, and residue scanning revealed that Arg688 of DNMT3A is involved in the interaction with this inhibitor, as seen by its significant contribution to the binding free energy. The presence of Asn1192 at the corresponding residues in DNMT1 results in a loss of affinity for the inhibitor, suggesting that the interactions mediated by Arg688 in DNMT3A are essential for selectivity. Our study findings can be applied in the design of DNMT-selective inhibitors and methylation-specific drug optimization procedures. © 2023, The Authors. All rights reserved.

关键词： Molecular dynamics

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Bulk-plasmon-mediated free-electron radiation beyond the conventional formation time

arXiv

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arXiv 2022年

作者： Tay, Fuyang Lin, Xiao Shi, Xihang Chen, Hongsheng Kaminer, Ido Zhang, Baile Interdisciplinary Center for Quantum Information State Key Laboratory of Modern Optical Instrumentation ZJUHangzhou Global Science and Technology Innovation Center College of Information Science and Electronic Engineering Zhejiang University Hangzhou310027 China Department of Electrical and Computer Engineering Rice University HoustonTX77005 United States Applied Physics Graduate Program Smalley–Curl Institute Rice University HoustonTX77005 United States International Joint Innovation Center The Electromagnetics Academy Zhejiang University Zhejiang University Haining314400 China Department of Electrical Engineering Technion-Israel Institute of Technology Haifa32000 Israel Jinhua Institute of Zhejiang University Zhejiang University Jinhua321099 China Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University 637371 Singapore Centre for Disruptive Photonic Technologies Nanyang Technological University 637371 Singapore

Free-electron radiation is a fundamental photon emission process that is induced by fast-moving electrons interacting with optical media. Historically, it has been understood that, just like any other photon emission process, free-electron radiation must be constrained within a finite time interval known as the "formation time", whose concept is applicable to both Cherenkov radiation and transition radiation, the two basic mechanisms describing radiation from a bulk medium and from an interface, respectively. Here we reveal an alternative mechanism of free-electron radiation far beyond the previously defined formation time. It occurs when a fast electron crosses the interface between vacuum and a plasmonic medium supporting bulk plasmons. While emitted continuously from the crossing point on the interface — thus consistent with the features of transition radiation — the extra radiation beyond the conventional formation time is supported by a long tail of bulk plasmons following the electron’s trajectory deep into the plasmonic medium. Such a plasmonic tail mixes surface and bulk effects, and provides a sustained channel for electron-interface interaction. These results also settle the historical debate in Ferrell radiation, regarding whether it is a surface or bulk effect, from transition radiation or plasmonic oscillation. Copyright © 2022, The Authors. All rights reserved.

关键词： Plasmonics

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The ALCHEMI atlas: principal component analysis reveals starburst evolution in NGC 253

arXiv

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arXiv 2024年

作者： Harada, Nanase Meier, David S. Martín, Sergio Muller, Sebastien Sakamoto, Kazushi Saito, Toshiki Gorski, Mark D. Henkel, Christian Tanaka, Kunihiko Mangum, Jeffrey G. Aalto, Susanne Aladro, Rebeca Bouvier, Mathilde Colzi, Laura Emig, Kimberly L. Herrero-Illana, Rubén Huang, Ko-Yun Kohno, Kotaro König, Sabine Nakanishi, Kouichiro Nishimura, Yuri Takano, Shuro Rivilla, Víctor M. Viti, Serena Watanabe, Yoshimasa van der Werf, Paul P. Yoshimura, Yuki National Astronomical Observatory of Japan 2-21-1 Osawa Mitaka Tokyo181-8588 Japan Institute of Astronomy and Astrophysics Academia Sinica 11F of AS/NTU Astronomy-Mathematics Building No.1 Sec. 4 Roosevelt Rd Taipei10617 Taiwan Astronomical Science Program Graduate Institute for Advanced Studies SOKENDAI 2-21-1 Osawa Mitaka Tokyo181-1855 Japan New Mexico Institute of Mining and Technology 801 Leroy Place SocorroNM87801 United States National Radio Astronomy Observatory PO Box O 1003 Lopezville Road SocorroNM87801 United States European Southern Observatory Alonso de Córdova 3107 Vitacura Santiago763-0355 Chile Joint ALMA Observatory Alonso de Córdova 3107 Vitacura Santiago763-0355 Chile Department of Space Earth and Environment Chalmers University of Technology Onsala Space Observatory OnsalaSE-439 92 Sweden Department of Physics and Astronomy Northwestern University EvanstonIL60208 United States Max-Planck-Institut für Radioastronomie Auf dem Hügel 69 Bonn53121 Germany Astronomy Department Faculty of Science King Abdulaziz University P. O. Box 80203 Jeddah21589 Saudi Arabia Department of Physics Faculty of Science and Technology Keio University 3-14-1 Hiyoshi Kanagawa Yokohama223-8522 Japan National Radio Astronomy Observatory 520 Edgemont Road CharlottesvilleVA22903-2475 United States Department of Space Earth and Environment Chalmers University of Technology GöteborgSE-412 96 Sweden Leiden Observatory Leiden University P.O. Box 9513 Leiden2300 RA Netherlands CSIC-INTA Ctra. de Ajalvir Km. 4 Torrejón de Ardoz Madrid28850 Spain Campus UAB Carrer de Magrans BarcelonaE-08193 Spain Institute of Astronomy Graduate School of Science The University of Tokyo 2-21-1 Osawa Mitaka Tokyo181-0015 Japan Department of Astronomy The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo113-0033 Japan ALMA Project National Astronomical Observatory of Japan 2-21-1 Osawa Mitaka Tokyo181-8588 Japan Department of Physic

Molecular lines are powerful diagnostics of the physical and chemical properties of the interstellar medium (ISM). These ISM properties, which affect future star formation, are expected to differ in starburst galaxies from those of more quiescent galaxies. We investigate the ISM properties in the central molecular zone of the nearby starburst galaxy NGC 253 using the ultra-wide millimeter spectral scan survey from the ALMA Large program ALCHEMI. We present an atlas of velocity-integrated images at a 1′′. 6 resolution of 148 unblended transitions from 44 species, including the first extragalactic detection of HCNH+ and the first interferometric images of C3H+, NO, HCS+. We conduct a principal component analysis (PCA) on these images to extract correlated chemical species and to identify key groups of diagnostic transitions. To the best of our knowledge, our dataset is currently the largest astronomical set of molecular lines to which PCA has been applied. The PCA can categorize transitions coming from different physical components in NGC 253 such as i) young starburst tracers characterized by high-excitation transitions of HC3N and complex organic molecules (COMs) versus tracers of on-going star formation (radio recombination lines) and high-excitation transitions of CCH and CN tracing PDRs, ii) tracers of cloud-collision-induced shocks (low-excitation transitions of CH3OH, HNCO, HOCO+, and OCS) versus shocks from star-formation-induced outflows (high-excitation transitions of SiO), as well as iii) outflows showing emission from HOC+, CCH, H3O+, CO isotopologues, HCN, HCO+, CS, and CN. Our findings show these intensities vary with galactic dynamics, star formation activities, and stellar feedback. © 2024, CC BY.

关键词： Principal component analysis

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Positive- And negative-frequency noise from an ensemble of two-level fluctuators

arXiv

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arXiv 2020年

作者： You, Xinyuan Clerk, Aashish A. Koch, Jens Northwestern–Fermilab Center for Applied Physics and Superconducting Technologies Northwestern University EvanstonIL60208 United States Graduate Program in Applied Physics Northwestern University EvanstonIL60208 United States Pritzker School of Molecular Engineering University of Chicago 5640 South Ellis Avenue ChicagoIL60637 United States Department of Physics and Astronomy Northwestern University EvanstonIL60208 United States

The analysis of charge noise based on the Bloch–Redfield treatment of an ensemble of dissipative two-level fluctuators generally results in a violation of the fluctuation–dissipation theorem. The standard Markov approximation can be identified as the main origin of this failure. The resulting decoherence rates only involve the bath response at the fluctuator frequency, and thus completely neglect the effects of frequency broadening. A systematic and computationally convenient way to overcome this issue is to employ the spectator-qubit method: by coupling an auxiliary qubit to the two-level fluctuator ensemble, an analytical approximation for S(ω) fully consistent with the fluctuation–dissipation theorem can be obtained. We discuss the resulting characteristics of the noise which exhibits distinct behavior over several frequency ranges, including a 1/f to 1/f2 crossover with a T3 temperature dependence of the crossover frequency. Copyright © 2020, The Authors. All rights reserved.

关键词： Qubits

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Measurement of ϕ-meson production in Cu+Au collisions at sNN=200 GeV and U+U collisions at sNN=193 GeV

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Physical Review C 2023年第1期107卷 014907-014907页

作者： N. J. Abdulameer U. Acharya C. Aidala N. N. Ajitanand Y. Akiba R. Akimoto J. Alexander M. Alfred M. Alibordi K. Aoki N. Apadula H. Asano E. T. Atomssa T. C. Awes B. Azmoun V. Babintsev M. Bai X. Bai B. Bannier K. N. Barish S. Bathe V. Baublis C. Baumann S. Baumgart A. Bazilevsky M. Beaumier R. Belmont A. Berdnikov Y. Berdnikov L. Bichon D. Black B. Blankenship D. S. Blau J. S. Bok V. Borisov K. Boyle M. L. Brooks J. Bryslawskyj H. Buesching V. Bumazhnov S. Butsyk S. Campbell V. Canoa Roman C.-H. Chen M. Chiu C. Y. Chi I. J. Choi J. B. Choi S. Choi P. Christiansen T. Chujo V. Cianciolo B. A. Cole M. Connors R. Corliss Y. Corrales Morales N. Cronin N. Crossette M. Csanád T. Csörgő L. D'Orazio A. Datta M. S. Daugherity G. David C. T. Dean K. Dehmelt A. Denisov A. Deshpande E. J. Desmond L. Ding V. Doomra J. H. Do O. Drapier A. Drees K. A. Drees J. M. Durham A. Durum T. Engelmore A. Enokizono R. Esha K. O. Eyser B. Fadem W. Fan D. E. Fields M. Finger, Jr. M. Finger D. Firak D. Fitzgerald F. Fleuret S. L. Fokin J. E. Frantz A. Franz A. D. Frawley Y. Fukao T. Fusayasu K. Gainey C. Gal P. Garg A. Garishvili I. Garishvili M. Giles F. Giordano A. Glenn X. Gong M. Gonin Y. Goto R. Granier de Cassagnac N. Grau S. V. Greene M. Grosse Perdekamp T. Gunji H. Guragain Y. Gu T. Hachiya J. S. Haggerty K. I. Hahn H. Hamagaki J. Hanks M. Harvey S. Hasegawa K. Hashimoto R. Hayano T. K. Hemmick T. Hester X. He J. C. Hill A. Hodges R. S. Hollis K. Homma B. Hong T. Hoshino J. Huang T. Ichihara Y. Ikeda K. Imai Y. Imazu M. Inaba A. Iordanova D. Isenhower A. Isinhue D. Ivanishchev B. V. Jacak S. J. Jeon M. Jezghani X. Jiang Z. Ji B. M. Johnson K. S. Joo D. Jouan D. S. Jumper J. Kamin S. Kanda B. H. Kang J. H. Kang J. S. Kang J. Kapustinsky D. Kawall A. V. Kazantsev J. A. Key V. Khachatryan P. K. Khandai A. Khanzadeev A. Khatiwada K. M. Kijima C. Kim D. J. Kim E.-J. Kim T. Kim Y.-J. Kim Y. K. Kim D. Kincses A. Kingan E. Kistenev J. Klatsky D. Kleinjan P. Kline T. Koblesky M. Kofarago B. Komkov J. Koster D. Kotchetkov D. Kotov L. Kovacs F. Debrecen University H-4010 Debrecen Egyetem tér 1 Hungary Georgia State University Atlanta Georgia 30303 USA Los Alamos National Laboratory Los Alamos New Mexico 87545 USA Department of Physics University of Michigan Ann Arbor Michigan 48109-1040 USA Chemistry Department Stony Brook University SUNY Stony Brook New York 11794-3400 USA RIKEN Nishina Center for Accelerator-Based Science Wako Saitama 351-0198 Japan RIKEN BNL Research Center Brookhaven National Laboratory Upton New York 11973-5000 USA Center for Nuclear Study Graduate School of Science University of Tokyo 7-3-1 Hongo Bunkyo Tokyo 113-0033 Japan Department of Physics and Astronomy Howard University Washington DC 20059 USA Mississippi State University Mississippi State Mississippi 39762 USA KEK High Energy Accelerator Research Organization Tsukuba Ibaraki 305-0801 Japan Iowa State University Ames Iowa 50011 USA Department of Physics and Astronomy Stony Brook University SUNY Stony Brook New York 11794-3800 USA Kyoto University Kyoto 606-8502 Japan Oak Ridge National Laboratory Oak Ridge Tennessee 37831 USA Physics Department Brookhaven National Laboratory Upton New York 11973-5000 USA IHEP Protvino State Research Center of Russian Federation Institute for High Energy Physics Protvino 142281 Russia Collider-Accelerator Department Brookhaven National Laboratory Upton New York 11973-5000 USA Science and Technology on Nuclear Data Laboratory China Institute of Atomic Energy Beijing 102413 People's Republic of China University of California-Riverside Riverside California 92521 USA Baruch College City University of New York New York New York 10010 USA PNPI Petersburg Nuclear Physics Institute Gatchina Leningrad Region 188300 Russia University of Colorado Boulder Colorado 80309 USA Physics and Astronomy Department University of North Carolina at Greensboro Greensboro North Carolina 27412 USA Vanderbilt University Nashville Tennessee 37235 USA Saint Petersburg State Polyte

The PHENIX experiment reports systematic measurements at the Relativistic Heavy Ion Collider of ϕ-meson production in asymmetric Cu+Au collisions at sNN=200GeV and in U+U collisions at sNN=193GeV. Measurements were performed via the ϕ→K+K− decay channel at midrapidity |η|<0.35. Features of ϕ-meson production measured in Cu+Cu, Cu+Au, Au+Au, and U+U collisions were found to not depend on the collision geometry, which was expected because the yields are averaged over the azimuthal angle and follow the expected scaling with nuclear-overlap size. The elliptic flow of the ϕ meson in Cu+Au, Au+Au, and U+U collisions scales with second-order-participant eccentricity and the length scale of the nuclear-overlap region (estimated with the number of participating nucleons). At moderate pT, ϕ-meson production measured in Cu+Au and U+U collisions is consistent with coalescence-model predictions, whereas at high pT the production is in agreement with expectations for in-medium energy loss of parent partons prior to their fragmentation. The elliptic flow for ϕ mesons measured in Cu+Au and U+U collisions is well described by a (2+1)-dimensional viscous-hydrodynamic model with specific-shear viscosity η/s=1/4π.

关键词： Leptonic, semileptonic & radiative decays Particle production Relativistic heavy-ion collisions Strange quark Vector mesons Hadron colliders

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Erratum to: Higgs boson production cross-section measurements and their EFT interpretation in the 4 ℓ decay channel at s = 13 TeV with the ATLAS detector

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The European Physical Journal C 2021年第5期81卷 1-15页

作者： Aad, G. Abbott, B. Abbott, D. C. Abud, A. Abed Abeling, K. Abhayasinghe, D. K. Abidi, S. H. AbouZeid, O. S. Abraham, N. L. Abramowicz, H. Abreu, H. Abulaiti, Y. Acharya, B. S. Achkar, B. Adam, L. Bourdarios, C. Adam Adamczyk, L. Adamek, L. Adelman, J. Adersberger, M. Adiguzel, A. Adorni, S. Adye, T. Affolder, A. A. Afik, Y. Agapopoulou, C. Agaras, M. N. Aggarwal, A. Agheorghiesei, C. Aguilar-Saavedra, J. A. Ahmad, A. Ahmadov, F. Ahmed, W. S. Ai, X. Aielli, G. Akatsuka, S. Åkesson, T. P. A. Akilli, E. Akimov, A. V. Khoury, K. Al Alberghi, G. L. Albert, J. Verzini, M. J. Alconada Alderweireldt, S. Aleksa, M. Aleksandrov, I. N. Alexa, C. Alexopoulos, T. Alfonsi, A. Alfonsi, F. Alhroob, M. Ali, B. Ali, S. Aliev, M. Alimonti, G. Allaire, C. Allbrooke, B. M. M. Allen, B. W. Allport, P. P. Aloisio, A. Alonso, F. Alpigiani, C. Camelia, E. Alunno Estevez, M. Alvarez Alviggi, M. G. Coutinho, Y. Amaral Ambler, A. Ambroz, L. Amelung, C. Amidei, D. Santos, S. P. Amor Dos Amoroso, S. Amrouche, C. S. An, F. Anastopoulos, C. Andari, N. Andeen, T. Anders, J. K. Andrean, S. Y. Andreazza, A. Andrei, V. Anelli, C. R. Angelidakis, S. Angerami, A. Anisenkov, A. V. Annovi, A. Antel, C. Anthony, M. T. Antipov, E. Antonelli, M. Antrim, D. J. A. Anulli, F. Aoki, M. Pozo, J. A. Aparisi Aparo, M. A. Bella, L. Aperio Barrio, N. Aranzabal Ferraz, V. Araujo Pereira, R. Araujo Arcangeletti, C. Arce, A. T. H. Arduh, F. A. Arguin, J-F. Argyropoulos, S. Arling, J.-H. Armbruster, A. J. Armstrong, A. Arnaez, O. Arnold, H. Tame, Z. P. Arrubarrena Artoni, G. Asai, K. Asai, S. Asawatavonvanich, T. Asbah, N. Asimakopoulou, E. M. Asquith, L. Assahsah, J. Assamagan, K. Astalos, R. Atkin, R. J. Atkinson, M. Atlay, N. B. Atmani, H. Augsten, K. Austrup, V. A. Avolio, G. Ayoub, M. K. Azuelos, G. Bachacou, H. Bachas, K. Backes, M. Backman, F. Bagnaia, P. Bahmani, M. Bahrasemani, H. Bailey, A. J. Bailey, V. R. Baines, J. T. Bakalis, C. Baker, O. K. Bakker, P. J. Bakos, E. Gupta, D. Bakshi Balaji, S. Baldin, E. M. Balek, P. Balli, F. Balunas, W. K. Balz, J. Ban CPPM Aix-Marseille Université CNRS/IN2P3 Marseille France Homer L. Dodge Department of Physics and Astronomy University of Oklahoma Norman USA Department of Physics University of Massachusetts Amherst USA CERN Geneva Switzerland II. Physikalisches Institut Georg-August-Universität Göttingen Göttingen Germany Department of Physics Royal Holloway University of London Egham UK Department of Physics University of Toronto Toronto Canada Niels Bohr Institute University of Copenhagen Copenhagen Denmark Department of Physics and Astronomy University of Sussex Brighton UK 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 USA INFN Gruppo Collegato di Udine Sezione di Trieste Udine Italy ICTP Trieste Italy Department of Physics King’s CollegeLondon London UK Institut für Physik Universität Mainz Mainz Germany LAPP Université Grenoble Alpes Université Savoie Mont Blanc CNRS/IN2P3 Annecy France Faculty of Physics and Applied Computer Science AGH University of Science and Technology Krakow Poland Department of Physics Northern Illinois University DeKalb 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 UK Santa Cruz Institute for Particle Physics University of California Santa Cruz Santa Cruz USA IJCLab Université Paris-Saclay CNRS/IN2P3 91405 Orsay France LPC Université Clermont Auvergne CNRS/IN2P3 Clermont-Ferrand France Institute for Mathematics Astrophysics and Particle Physics Radboud University Nijmegen/Nikhef Nijmegen The Netherlands Department of Physics Alexandru Ioan Cuza University of Iasi Iasi Romania Lab

A Correction to this paper has been published: https://***/10.1140/epjc/s10052-020-8227-9

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Cosmic-ray acceleration and escape from supernova remnant W44 as probed by Fermi-LAT and MAGIC

arXiv

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arXiv 2025年

作者： Abe, S. Abhir, J. Abhishek, A. Acciari, V.A. Aguasca-Cabot, A. Agudo, I. Aniello, T. Ansoldi, S. Antonelli, L.A. Arbet Engels, A. Arcaro, C. Asano, K. Babić, A. Baquero, A. Barres de Almeida, U. Barrio, J.A. Batković, I. Bautista, A. Baxter, J. Becerra González, J. Bednarek, W. Bernardini, E. Bernete, J. Berti, A. Besenrieder, J. Bigongiari, C. Biland, A. Blanch, O. Bonnoli, G. Bošnjak, Ž. Bronzini, E. Burelli, I. Busetto, G. Campoy-Ordaz, A. Carosi, A. Carosi, R. Carretero-Castrillo, M. Castro-Tirado, A.J. Cerasole, D. Ceribella, G. Chai, Y. Chilingarian, A. Cifuentes, A. Colombo, E. Contreras, J.L. Cortina, J. Covino, S. D'Amico, G. D'Elia, V. Da Vela, P. Dazzi, F. De Angelis, A. De Lotto, B. de Menezes, R. Del Popolo, A. Delfino, M. Delgado, J. Delgado Mendez, C. Di Pierro, F. Dominis Prester, D. Donini, A. Dorner, D. Doro, M. Elsaesser, D. Emery, G. Escudero, J. Fariña, L. Fattorini, A. Foffano, L. Font, L. Fröse, S. Fukazawa, Y. García López, R.J. Garczarczyk, M. Gasparyan, S. Gaug, M. Giesbrecht Paiva, J.G. Giglietto, N. Gliwny, P. Godinović, N. Gozzini, S.R. Gradetzke, T. Grau, R. Green, J.G. Günther, P. Hadasch, D. Hahn, A. Hassan, T. Heckmann, L. Herrera, J. Hrupec, D. Hütten, M. Imazawa, R. Ishio, K. Jiménez Martínez, I. Jormanainen, J. Kayanoki, T. Kerszberg, D. Kluge, G.W. Kobayashi, Y. Kouch, P.M. Kubo, H. Kushida, J. Láinez, M. Lamastra, A. Leone, F. Lindfors, E. Linhoff, L. Lombardi, S. Longo, F. López-Coto, R. López-Moya, M. López-Oramas, A. Loporchio, S. Lorini, A. Lyard, E. Machado de Oliveira Fraga, B. Majumdar, P. Makariev, M. Maneva, G. Mang, N. Manganaro, M. Mangano, S. Mannheim, K. Mariotti, M. Martínez, M. Martínez-Chicharro, M. Mas-Aguilar, A. Mazin, D. Menchiari, S. Mender, S. Miceli, D. Miener, T. Miranda, J.M. Mirzoyan, R. Molero González, M. Molina, E. Mondal, H.A. Moralejo, A. Morcuende, D. Nakamori, T. Nanci, C. Nava, L. Neustroev, V. Nickel, L. Nievas Rosillo, M. Nigro, C. Nikolić, L. Nishijima, K. Njoh Ekoume, T. The University of Tokyo Chiba Kashiwa277-8582 Japan ETH Zürich ZürichCH-8093 Switzerland Università di Siena INFN Pisa SienaI-53100 Italy Instituto de Astrofísica de Canarias Dpto. de Astrofísica Universidad de La Laguna Tenerife La LagunaE-38200 Spain Universitat de Barcelona ICCUB IEEC-UB BarcelonaE-08028 Spain Instituto de Astrofísica de Andalucía-CSIC Glorieta de la Astronomía s/n Granada18008 Spain RomeI-00136 Italy Università di Udine INFN Trieste UdineI-33100 Italy Max-Planck-Institut für Physik GarchingD-85748 Germany Università di Padova INFN PadovaI-35131 Italy Zagreb10000 Croatia IPARCOS Institute EMFTEL Department Universidad Complutense de Madrid MadridE-28040 Spain 22290-180 URCA RJ Rio de Janeiro22290-180 Brazil University of Lodz Faculty of Physics and Applied Informatics Department of Astrophysics Lodz90-236 Poland Centro de Investigaciones Energéticas Medioambientales y Tecnológicas MadridE-28040 Spain Bellaterra BarcelonaE-08193 Spain Departament de Física CERES-IEEC Universitat Autònoma de Barcelona BellaterraE-08193 Spain Università di Pisa INFN Pisa PisaI-56126 Italy INFN MAGIC Group INFN Sezione di Bari Dipartimento Interateneo di Fisica Università e del Politecnico di Bari BariI-70125 Italy Armenian MAGIC Group A. Alikhanyan National Science Laboratory Yerevan0036 Armenia Department for Physics and Technology University of Bergen Norway INFN MAGIC Group INFN Sezione di Torino Università degli Studi di Torino TorinoI-10125 Italy INFN MAGIC Group INFN Sezione di Catania Dipartimento di Fisica e Astronomia University of Catania CataniaI-95123 Italy Croatian MAGIC Group University of Rijeka Faculty of Physics Rijeka51000 Croatia Universität Würzburg WürzburgD-97074 Germany Technische Universität Dortmund DortmundD-44221 Germany University of Geneva Chemin d'Ecogia 16 VersoixCH-1290 Switzerland Japanese MAGIC Group: Physics Program Graduate School of Advanced Science and Engin

Context. The supernova remnant (SNR) W44 and its surroundings are a prime target for studying the acceleration of cosmic rays (CRs). Several previous studies established an extended gamma-ray emission that is set apart from the radio shell of W44. This emission is thought to originate from escaped high-energy CRs that interact with a surrounding dense molecular cloud complex. Aims. We present a detailed analysis of Fermi-LAT data with an emphasis on the spatial and spectral properties of W44 and its surroundings. We also report the results of the observations performed with the MAGIC telescopes of the northwestern region of W44. Finally, we present an interpretation model to explain the gamma-ray emission of the SNR and its surroundings. Methods. We first performed a detailed spatial analysis of 12 years of Fermi-LAT data at energies above 1 GeV, in order to exploit the better angular resolution, while we set a threshold of 100 MeV for the spectral analysis. We performed a likelihood analysis of 174 hours of MAGIC data above 130 GeV using the spatial information obtained with Fermi-LAT. Results. The combined spectra of Fermi-LAT and MAGIC, extending from 100 MeV to several TeV, were used to derive constraints on the escape of CRs. Using a time-dependent model to describe the particle acceleration and escape from the SNR, we show that the maximum energy of the accelerated particles has to be 40 GeV. However, our gamma-ray data suggest that a small number of lower-energy particles also needs to escape. We propose a novel model, the broken-shock scenario, to account for this effect and explain the gamma-ray emission. Copyright © 2025, The Authors. All rights reserved.

关键词： Cosmic rays

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Functional observability and target state estimation in large-scale networks

arXiv

引用

arXiv 2022年

作者： Montanari, Arthur N. Duan, Chao Aguirre, Luis A. Motter, Adilson E. Department of Physics and Astronomy Northwestern University EvanstonIL60208 United States Graduate Program in Electrical Engineering Federal University of Minas Gerais Belo HorizonteMG 31270-901 Brazil Luxembourg Centre for Systems Biomedicine University of Luxembourg BelvauxL-4367 Luxembourg Departament of Electronic Engineering Federal University of Minas Gerais Belo HorizonteMG 31270-901 Brazil Northwestern Institute on Complex Systems Northwestern University EvanstonIL60208 United States

The quantitative understanding and precise control of complex dynamical systems can only be achieved by observing their internal states via measurement and/or estimation. In large-scale dynamical networks, it is often difficult or physically impossible to have enough sensor nodes to make the system fully observable. Even if the system is in principle observable, high-dimensionality poses fundamental limits on the computational tractability and performance of a full-state observer. To overcome the curse of dimensionality, we instead require the system to be functionally observable, meaning that a targeted subset of state variables can be reconstructed from the available measurements. Here, we develop a graph-based theory of functional observability, which leads to highly scalable algorithms to i) determine the minimal set of required sensors and ii) design the corresponding state observer of minimum order. Compared to the full-state observer, the proposed functional observer achieves the same estimation quality with substantially less sensing and computational resources, making it suitable for large-scale networks. We apply the proposed methods to the detection of cyber-attacks in power grids from limited phase measurement data and the inference of the prevalence rate of infection during an epidemic under limited testing conditions. The applications demonstrate that the functional observer can significantly scale up our ability to explore otherwise inaccessible dynamical processes on complex networks. Copyright © 2022, The Authors. All rights reserved.

关键词： State estimation

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MAGIC and H.E.S.S. detect VHE gamma rays from the blazar OT 081 for the first time: a deep multiwavelength study 37

MAGIC and H.E.S.S. detect VHE gamma rays from the blazar OT ...

引用

37th International Cosmic Ray Conference, ICRC 2021

作者： Seglar-Arroyo, M. Sanchez, D. Esteban Gutierrez, A. Agudo, I. Ciprini, S. Filippenko, A.V. Hovatta, T. Jermak, H. Kopatskaya, E.N. Lähteenmäki, A. Larionov, V.M. Larionova, L.V. Morozova, D.A. Pahljina, M. Tornikoski, M. Troitsky, I. Verrecchia, F. Xiao, H.B. Zheng, W. Acciari, V.A. Ansoldi, S. Antonelli, L.A. Arbet Engels, A. Artero, M. Asano, K. Baack, D. Babić, A. Baquero, A. Barres de Almeida, U. Barrio, J.A. Batković, I. Becerra González, J. Bednarek, W. Bellizzi, L. Bernardini, E. Bernardos, M. Berti, A. Besenrieder, J. Bhattacharyya, W. Bigongiari, C. Biland, A. Blanch, O. Bökenkamp, H. Bonnoli, G. Bošnjak, Ž. Busetto, G. Carosi, R. Ceribella, G. Cerruti, M. Chai, Y. Chilingarian, A. Cikota, S. Colak, S.M. Colombo, E. Contreras, J.L. Cortina, J. Covino, S. D'Amico, G. D'Elia, V. Da Vela, P. Dazzi, F. De Angelis, A. De Lotto, B. Delfino, M. Delgado, J. Delgado Mendez, C. Depaoli, D. Di Pierro, F. Di Venere, L. Do Souto Espiñeira, E. Dominis Prester, D. Donini, A. Dorner, D. Doro, M. Elsaesser, D. Fallah Ramazani, V. Fattorini, A. Fonseca, M.V. Font, L. Fruck, C. Fukami, S. Fukazawa, Y. García López, R.J. Garczarczyk, M. Gasparyan, S. Gaug, M. Giglietto, N. Giordano, F. Gliwny, P. Godinović, N. Green, J.G. Green, D. Hadasch, D. Hahn, A. Heckmann, L. Herrera, J. Hoang, J. Hrupec, D. Hütten, M. Inada, T. Ishio, K. Iwamura, Y. Jiménez Martínez, I. Jormanainen, J. Jouvin, L. Karjalainen, M. Kerszberg, D. Kobayashi, Y. Kubo, H. Kushida, J. Lamastra, A. Lelas, D. Leone, F. Lindfors, E. Linhoff, L. Lombardi, S. Longo, F. López-Coto, R. López-Moya, M. López-Oramas, A. Loporchio, S. Machado de Oliveira Fraga, B. Maggio, C. Majumdar, P. Makariev, M. Mallamaci, M. Maneva, G. Manganaro, M. Mannheim, K. Maraschi, L. Mariotti, M. Martínez, M. Mazin, D. Menchiari, S. Mender, S. Mićanović, S. Miceli, D. Miener, T. Miranda, J.M. Mirzoyan, R. Molina, E. Moralejo, A. Morcuende, D. Moreno, V. Moretti, E. Nakamori, T. Nava, L. Neustroev, V. University of Rijeka Department of Physics Radmile Matejčić 2 Rijeka Croatia IRFU CEA Université Paris-Saclay Gif-sur-YvetteF-91191 France CNRS LAPP France CSIC Granada Spain Roma Tor Vergata Section RomeI-00133 Italy ASI Space Science Data Center RomeI-00133 Italy Department of Astronomy University of California BerkeleyCA94720-3411 United States Miller Institute for Basic Research in Science University of California BerkeleyCA94720 United States Aalto University Tuorla observatory Finland Liverpool John Moores University United Kingdom St. Petersburg State University Russia Aalto University Finland INAF Osservatorio Astronomico di Roma via Frascati 33 Monte Porzio CatoneI-00078 Italy Guangzhou University China Instituto de Astrofísica de Canarias Dpto. de Astrofísica Universidad de La Laguna Tenerife La LagunaE-38200 Spain Università di Udine INFN Trieste UdineI-33100 Italy RomeI-00136 Italy ETH Zürich ZürichCH-8093 Switzerland E-08193 Spain The University of Tokyo Chiba Kashiwa277-8582 Japan Technische Universität Dortmund DortmundD-44221 Germany Zagreb10000 Croatia IPARCOS Institute EMFTEL Department Universidad Complutense de Madrid MadridE-28040 Spain URCA RJ Rio de Janeiro22290-180 Brazil Università di Padova INFN PadovaI-35131 Italy University of Lodz Faculty of Physics and Applied Informatics Department of Astrophysics Lodz90-236 Poland Università di Siena INFN Pisa SienaI-53100 Italy ZeuthenD-15738 Germany Max-Planck-Institut für Physik MünchenD-80805 Germany Instituto de Astrofísica de Andalucía-CSIC Glorieta de la Astronomía s/n Granada18008 Spain Università di Pisa INFN Pisa PisaI-56126 Italy Universitat de Barcelona ICCUB IEEC-UB BarcelonaE-08028 Spain Armenian MAGIC Group A. Alikhanyan National Science Laboratory Yerevan0036 Armenia Centro de Investigaciones Energéticas Medioambientales y Tecnológicas MadridE-28040 Spain INFN MAGIC Group INFN Sezione di Torino Università d

OT 081 is a luminous blazar well known for its variability in many energy bands. The very-high-energy (VHE;E > 100 GeV) gamma-ray emission from the source was discovered by MAGIC and H.E.S.S. during flaring activity in July 2016, after a trigger from the Large Area Telescope (LAT) onboard the Fermi satellite. By analysing the multiwavelength light curves and the broadband spectral energy distribution (SED), we study the activity of the source and investigate four individual states of activity in the window from MJD 57575 to 57602. The intrinsic gamma-ray spectrum can be described by a power law with spectral indices of 3.27 ± 0.44 (MAGIC) and 3.39 ± 0.58 (H.E.S.S.) over energy ranges 60-300 GeV and 120-500 GeV, respectively. The combined contemporaneous high-energy (HE;E > 100 MeV) through VHE SED shows curvature and can be described by a log-parabola shape. A simple one-zone synchrotron self-Compton (SSC) model is not sufficient to describe the broadband SED. The presence of broad emission lines in the optical spectrum of the source challenges the categorisation of OT 081 as a BL Lac and, together with the emission scenarios tested, points to the possibility that the source is transitional in nature between a BL Lac and a flat-spectrum radio quasar. © Copyright owned by the author(s) under the terms of the Creative Commons.

关键词： Germanium alloys

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