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arXiv 2023年

作者： Wang, Chaoqian Szolnoki, Attila Department of Computational and Data Sciences George Mason University FairfaxVA22030 United States Institute of Technical Physics and Materials Science Centre for Energy Research P.O. Box 49 BudapestH-1525 Hungary

Due to limited cognitive skills for perceptual error or other emotional reasons, players may keep their current strategies even if there is a more promising choice. Such behavior inertia has already been studied, but its consequences remained unexplored in the weak selection limit. To fill this gap, we consider a spatial public goods game model where inertia is considered during the imitation process. By using the identity-by-descent method, we present analytical forms of the critical synergy factor which determines when cooperation is favored. We find that inertia hinders cooperation, which can be explained by the decelerated coarsening process under weak selection. Interestingly, the critical synergy conditions for different updating protocols, including death-birth and birth-death rules, can be formally linked by the extreme limits of the inertia factor. To explore the robustness of our observations, calculations are made for different lattices and group sizes. Monte Carlo simulations also confirm the results. © 2023, CC0.

关键词： Coarsening

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Pixel-level APS Sensor Integration and Sensitivity Scaling for Vision Based Speed Measurement

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Procedia Engineering 2016年 168卷 1321-1324页

作者： M. Németh Á. Zarándy P. Földesy Computational Optical Sensing and Processing Laboratory Computer and Research Automation Institute Hungarian Academy of Sciences MTA-SZTAKI Budapest Hungary Faculty of Information Technology Péter Pázmány Catholic University PPKE-ITK Budapest Hungary Institute of Technical Physics and Materials Science Centre for Energy Research – HAS Budapest Hungary

A dual-pixel APS sensor architecture is proposed in this paper, for vision based speed measurement applications, based on a novel double exposure method. The sensor integrates two type of imaging elements on pixel level, and is designed to generate two spatially and temporally coherent images. The primary sensor generates a good quality image for vehicle identification, while the output of the secondary sensor is used to calculate speed estimates, based on the intra-frame displacement of the vehicle's headlight. A scaling process has also been developed for the sensitivity of the secondary sensor, based on photodiode parasitic capacitor discharge time.

关键词： CMOS sensor Quantum efficiency Multi exposure Speed estimation Dual-pixel

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Galactic interstellar scintillation observed from four globular cluster pulsars by FAST

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Science China(physics,Mechanics & Astronomy) 2023年第9期66卷 119-127页

作者： Dandan Zhang Zhenzhao Tao Mao Yuan Jumei Yao Pei Wang Qijun Zhi Weiwei Zhu Xun Shi Michael Kramer Di Li Lei Zhang Guangxing Li School of Mathematical Sciences School of Physics and Electronic SciencesGuizhou Normal UniversityGuiyang 550001China National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guiyang 550001China Department of Astronomy Beijing Normal UniversityBeijing 100875China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China South-Western Institute for Astronomy Research(SWIFAR) Yunnan UniversityKunming 650000China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Max-Planck Institut fr Radioastronomie Bonn D-53121Germany Key Laboratory of Radio Astronomy and Technology Chinese Academy of SciencesBeijing 100101China Computational Astronomy Platform Zhejiang LabHangzhou 311121China

We report detections of scintillation arcs for pulsars in globular clusters M5,M13 and M15 for the first time using the Fivehundred-meter Aperture Spherical radio Telescope(FAST).From observations of these arcs at multiple epochs,we infer that screen-like scattering medium exists at distances 4.1_(-0.3)^(+0.2),6.7_(-0.2)^(+0.2)and 1.3_(-1.0)^(+0.7) kpc from Earth in the directions of M5,M13 and M15,*** means M5's and M13's scattering screens are located at 3.0_(-0.2)^(+0.1) and 4.4_(-0.1)^(+0.1) kpc above the galactic plane,whereas,M15's is at 0.6_(-0.5)^(+0.3) kpc below the *** estimate the scintillation timescale and decorrelation bandwidth for each pulsar at each epoch using the one-dimensional auto-correlation in frequency and time of the dynamic *** found that the boundary of the Local Bubble may have caused the scattering of M15,and detected the most distant off-plane scattering screens to date through pulsar scintillation,which provides evidence for understanding the medium circulation in the Milky Way.

关键词： pulsars scintillation globular clusters

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Dense matter with eXTP

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Science China(physics,Mechanics & Astronomy) 2019年第2期62卷 28-44页

作者： Anna L.Watts WenFei Yu Juri Poutanen Shu Zhang Sudip Bhattacharyya Slavko Bogdanov Long Ji Alessandro Patruno Thomas E.Riley Pavel Bakala Altan Baykal Federico Bernardini Ignazio Bombaci Edward Brown Yuri Cavecchi Deepto Chakrabarty Jér?me Chenevez Nathalie Degenaar Melania Del Santo Tiziana Di Salvo Victor Doroshenko Maurizio Falanga Robert D.Ferdman Marco Feroci Angelo F.Gambino MingYu Ge Svenja K.Greif Sebastien Guillot Can Gungor Dieter H.Hartmann Kai Hebeler Alexander Heger Jeroen Homan Rosario Iaria Jean in 't Zand Oleg Kargaltsev Aleksi KurkelaTheoretical physics Department CERN XiaoYu Lai Ang Li XiangDong Li ZhaoSheng Li Manuel Linares FangJun Lu Simin Mahmoodifar Mariano Méndez M.Coleman Miller Sharon Morsink Joonas N?ttil? Andrea Possenti Chanda Prescod-Weinstein JinLu Qu Alessandro Riggio Tuomo Salmi Andrea Sanna Andrea Santangelo Hendrik Schatz Achim Schwenk LiMing Song Eva?rámková Benjamin Stappers Holger Stiele Tod Strohmayer Ingo Tews Laura Tolos Gabriel T?r?k David Tsang Martin Urbanec Andrea Vacchi RenXin Xu YuPeng Xu Silvia Zane GuoBao Zhang ShuangNan Zhang WenDa Zhang ShiJie Zheng Xia Zhou Anton Pannekoek Institute for Astronomy University of Amsterdam Shanghai Astronomical Observatory Tuorla Observatory Department of Physics and Astronomy University of Turku Nordita KTH Royal Institute of Technology and Stockholm University Institute of High Energy Physics Chinese Academy Sciences Tata Institute of Fundamental Research Columbia Astrophysics Laboratory Columbia University Institut für Astronomie und Astrophysik Tübingen Universit?t Tübingen Leiden Observatory Leiden University Research Center for Computational Physics and Data Processing Silesian University in Opava Physics Department Middle East Technical University INAF Osservatorio Astronomico di Roma New York University Abu Dhabi Dipartimento di Fisica Enrico Fermi University of Pisa INFN Italian National Institute for Nuclear Physics Department of Physics and Astronomy Michigan State University Department of Astrophysical Sciences Princeton University Mathematical Sciences and STAG Research Centre University of Southampton MIT Kavli Institute for Astrophysics and Space Research DTU Space Technical University of Denmark INAF/IASF Palermo via Ugo La Malfa 153 Universita degli Studi di Palermo Dipartimento di Fisica e Chimica International Space Science Institute (ISSI) Faculty of Science University of East Anglia INAF Istituto di Astrofisica e Planetologie Spaziali Institut für Kernphysik Technische Universit?t Darmstadt ExtreMe Matter Institute EMMI GSI Helmholtzzentrum für Schwerionenforschung GmbH Instituto de Astrof'?sica Pontificia Universidad Católica de Chile Department of Physics & Astronomy Kinard Lab of Physics Clemson University School of Physics and Astronomy Monash University SRON Netherlands Institute for Space Research Department of Physics The George Washington University Faculty of Science and Technology University of Stavanger School of Physics and Mechanical & Electrical Engineering Hubei University of Education Department of Astronomy Xiamen University (Haiyun Campus) School of Astronomy and Space

In this White Paper we present the potential of the Enhanced X-ray Timing and Polarimetry(eXTP) mission for determining the nature of dense matter; neutron star cores host an extreme density regime which cannot be replicated in a terrestrial laboratory. The tightest statistical constraints on the dense matter equation of state will come from pulse profile modelling of accretion-powered pulsars, burst oscillation sources, and rotation-powered pulsars. Additional constraints will derive from spin measurements, burst spectra, and properties of the accretion flows in the vicinity of the neutron star. Under development by an international Consortium led by the Institute of High Energy physics of the Chinese Academy of Sciences, the eXTP mission is expected to be launched in the mid 2020 s.

关键词： neutron X-rays dense matter equation of state

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hddata360r: A high-dimensional panel data compiler for governance, trade, and competitiveness indicators of World Bank Group platforms

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SoftwareX 2023年 21卷

作者： Kurbucz, Marcell T. Department of Computational Sciences Wigner Research Centre for Physics 29-33 Konkoly-Thege Miklós Street BudapestH-1121 Hungary Institute of Data Analytics and Information Systems Corvinus University of Budapest 8 Fővám Square BudapestH-1093 Hungary

The World Bank Group's Govdata360 and TCdata360 platforms are widely employed in socio-economic research. The thousands of governance, trade, and competitiveness indicators they contain served as the basis for much research in the field of economic, developmental, and cultural studies, coronavirus disease 2019-related research, and tourism, to state a few. The presented R package called hddata360r collects thousands of up-to-date annual indicators from these platforms for all countries worldwide. Furthermore, it allows missing value imputation with data from previous years, and optionally, it exports the generated dataset into tab-separated value (TSV) files. The hddata360r R package with a sample dataset it generates is available publicly on GitHub and Mendeley data. © 2022 The Author(s)

关键词： Commerce

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Fast digital spectrometer for mixed radiation fields

Fast digital spectrometer for mixed radiation fields

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IEEE Sensors

作者： Martin Pavelek Zdenek Matej Ondrej Herman Filip Mravec Martin Veskrna Vaclav Pfenosil Frantisek Cvachovec Michal Kost'al Department of Machine Learning and Data Processing Masaryk University Brno Czech Republic Masarykova univerzita Brno JihomoravskÃ½ CZ Department of Mathematics and Physics University of Defence Brno Czech Republic Research Centre Rez Husinec-Řež Czech Republic

We present a digital system for measurement of neutron spectra in mixed gamma-neutron fields. The signal from a standard scintillation detector is sampled at rate up to 1 GHz, using 12-bit analog-to-digital converters. First stage of the signal processing is performed on a Virtex 6 FPGA and partial results are streamed through a fast Ethernet link to a computer, where the final processing takes place. The combination of high performance ADCs and flexible FPGA fabric allows the system to reliably process up to 100,000 detection events per second. This greatly reduces the time needed for data acquisition, compared to its analog predecessor that reached count rates approximately 30 times lower. The second main advantage over old analog spectrometers and earlier digital systems with similar parameters is a great reduction of storage space requirements, achieved by performing particle discrimination on-the-fly using the FPGA. A typical experiment that previously required several gigabytes of storage space to store all the raw data samples now requires only a few megabytes to store the measured energy and discrimination parameter for each detected particle.

关键词： Neutrons Field programmable gate arrays Detectors Photonics Standards Reliability Atmospheric measurements

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Accretion in strong field gravity with eXTP

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Science China(physics,Mechanics & Astronomy) 2019年第2期62卷 45-73页

作者： Alessandra De Rosa Phil Uttley LiJun Gou Yuan Liu Cosimo Bambi Didier Barret Tomaso Belloni Emanuele Berti Stefano Bianchi Ilaria Caiazzo Piergiorgio Casella Marco Feroci Valeria Ferrari Leonardo Gualtieri Jeremy Heyl Adam Ingram Vladimir Karas FangJun Lu Bin Luo Giorgio Matt Sara Motta Joseph Neilsen Paolo Pani Andrea Santangelo XinWen Shu JunFeng Wang Jian-Min Wang YongQuan Xue YuPeng Xu WeiMin Yuan YeFei Yuan Shuang-Nan Zhang Shu Zhang Ivan Agudo Lorenzo Amati Nils Andersson Cristina Baglio Pavel Bakala Altan Baykal Sudip Bhattacharyya Ignazio Bombaci NiccolóBucciantini Fiamma Capitanio Riccardo Ciolfi Wei K.Cui Filippo D'Ammando Thomas Dauser Melania Del Santo Barbara De Marco Tiziana Di Salvo Chris Done Michal Dovciak Andrew C.Fabian Maurizio Falanga Angelo Francesco Gambino Bruce Gendre Victoria Grinberg Alexander Heger Jeroen Homan Rosario Iaria JiaChen Jiang ChiChuan Jin Elmar Koerding Manu Linares Zhu Liu Thomas J.Maccarone Julien Malzac Antonios Manousakis Frédéric Marin Andea Marinucci Missagh Mehdipour Mariano Méndez Simone Migliari Cole Miller Giovanni Miniutti Emanuele Nardini Paul T.O'Brien Julian P.Osborne Pierre Olivier Petrucci Andrea Possenti Alessandro Riggio Jerome Rodriguez Andrea Sanna LiJing Shao Malgosia Sobolewska Eva Sramkova Abigail L.Stevens Holger Stiele Giulia Stratta Zdenek Stuchlik Jiri Svoboda Fabrizio Tamburini Thomas M.Tauris Francesco Tombesi Gabriel Torok Martin Urbanec Frederic Vincent QingWen Wu Feng Yuan Jean J.M.in't Zand Andrzej A.Zdziarski XinLin Zhou INAF-Istituto di Astrofisica e Planetologie Spaziali Via Fosso del Cavaliere Anton Pannekoek Institute for Astronomy University of Amsterdam National Astronomical Observatories Chinese Academy of Science Institute of High Energy Physics Chinese Academy of Science Center for Field Theory and Particle Physics and Department of Physics Fudan University IRAP Universitéde ToulouseCNRSUPSCNES INAF-Osservatorio Astronomico di Brera Department of Physics and Astronomy The University of MississippiUniversity Dipartimento di Matematica e Fisica Universitàdegli studi Roma Tre University of British Columbia INAF-Osservatorio Astronomico di Roma INFN-Roma 2 c/o Dipartimento di Fisica II Universit?di Roma"Tor Vergata" Dipartimento di Fisica Universitàdegli Studi di Roma"La Sapienza"&Sezione INFN Roma1 Department of Physics University of OxfordClarendon Laboratory Astronomical Institute Academy of Sciences School of Astronomy and Space Science Nanjing University MIT Kavli Institute for Astrophysics and Space Research Institut für Astronomie und Astrophysik Eberhard Karls Universität Department of Physics Anhui Normal University Department of Astronomy and Institute of Theoretical Physics and Astrophysics Xiamen University CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of China Instituto de Astrofísica de Andalucia(CSIC) Glorieta de la Astronomía s/n INAF-Istituto di Astrofisica Spaziale e Fisica cosmica di Bologna Mathematical Sciences and STAG Research Centre University of Southampton New York University Abu Dhabi Institute of Physics and Research Centre for Computational Physics and Data Processing Faculty of Philosophy&ScienceSilesian University in OpavaíBezru?ovo nám. Department of Physics Middle East Technical University Department of Astronomy and Astrophysics Tata Institute of Fundamental Research Dipartimento di Fisica Universit?di Pisa&INFN INAF-Osservatorio Astrofisico di Arcetri INAF-Osservatorio Astronomico di Padova INFN-TIFPA Trento Ins

In this paper we describe the potential of the enhanced X-ray Timing and Polarimetry(eXTP) mission for studies related to accretion flows in the strong field gravity regime around both stellar-mass and supermassive black-holes. eXTP has the unique capability of using advanced "spectral-timing-polarimetry" techniques to analyze the rapid variations with three orthogonal diagnostics of the flow and its geometry, yielding unprecedented insight into the inner accreting regions, the effects of strong field gravity on the material within them and the powerful outflows which are driven by the accretion process.

关键词： X-ray black holes physics accretion

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Fitting the light curves of Sagittarius A* with a hot-spot model

arXiv

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arXiv 2023年

作者： Yfantis, A.I. Mościbrodzka, M.A. Wielgus, M. Vos, J.T. Jimenez-Rosales, A. Department of Astrophysics IMAPP Radboud University P.O. Box 9010 Nijmegen6500 GL Netherlands Max-Planck-Institut für Radioastronomie Auf dem Hügel 69 Bonn53121 Germany Research Centre for Computational Physics and Data Processing Institute of Physics Silesian University in Opava Bezručovo nám. 13 OpavaCZ-746 01 Czech Republic

Context. Sagittarius A* (Sgr A*) exhibits frequent flaring activity across the electromagnetic spectrum. Signatures of an orbiting hot spot have been identified in the polarized millimeter wavelength light curves observed with ALMA in 2017 immediately after an X-ray flare. The nature of these hot spots remains uncertain. Aims. We expanded existing theoretical hot-spot models created to describe the Sgr A* polarized emission at millimeter wavelengths. We sampled the posterior space, identifying best-fitting parameters and characterizing uncertainties. Methods. Using the numerical radiative transfer code ipole, we defined a semi-analytical model describing a ball of plasma orbiting Sgr A*, threaded with a magnetic field and emitting synchrotron radiation. We then explored the posterior space in the Bayesian framework of dynesty. We fit the static background emission separately, using a radiatively inefficient accretion flow model. Results. We considered eight models with a varying level of complexity, distinguished by choices regarding dynamically important cooling, non-Keplerian motion, and magnetic field polarity. All models converge to realizations that fit the data, but one model without cooling, non-Keplerian motion, and magnetic field pointing toward us improved the fit significantly and also matched the observed circular polarization. Conclusions. Our models represent observational data well and allow testing various effects in a systematic manner. From our analysis, we have inferred an inclination of ∼ 155 − 160 deg, which corroborates previous estimates, a preferred period of ∼ 90 minutes, and an orbital radius of 9 − 12.0 gravitational radii. Our non-Keplerian models indicate a preference for an orbital velocity of 0.6-0.9 times the Keplerian value. Last, all our models agree on a high dimensionless spin value (a∗ > 0.8), but the impact of spin on the corresponding light curves is subdominant with respect to other parameters. © 2023, CC BY.

关键词： Polarization

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Puffy accretion disks: sub-Eddington, optically thick, and stable

arXiv

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arXiv 2019年

作者： Lančová, Debora Abarca, David Kluźniak, Wlodek Wielgus, Maciek Sadowski, Aleksander Narayan, Ramesh Schee, Jan Török, Gabriel Abramowicz, Marek Research Center for Computational Physics and Data Processing Research Centre of Theoretical Physics and Astrophysics Institute of Physics Silesian University in Opava Czech Republic Black Hole Initiative at Harvard University 20 Garden Street CambridgeMA02138 United States Nicolaus Copernicus Astronomical Centre Polish Academy of Sciences Bartycka 18 Warsaw00-716 Poland Center for Astrophysics Harvard & Smithsonian 60 Garden Street CambridgeMA02138 United States Akuna Capital 333 South Wabash Av. ChicagoIL60604 United States Department of Physics Göteborg University Sweden

We report on a new class of solutions of black hole accretion disks that we have found through three-dimensional, global, radiative magnetohydrodynamic simulations in general relativity. It combines features of the canonical thin, slim and thick disk models but differs in crucial respects from each of them. We expect these new solutions to provide a more realistic description of black hole disks than the slim disk model. We are presenting a disk solution for a non-spinning black hole at a sub-Eddington mass accretion rate, M = 0.6 M Edd. By the density scale-height measure the disk appears to be thin, having a high density core near the equatorial plane of height hρ ∼ 0.1 r, but most of the inflow occurs through a highly advective, turbulent, optically thick, Keplerian region that sandwiches the core and has a substantial geometrical thickness comparable to the radius, H ∼ r. The accreting fluid is supported above the midplane in large part by the magnetic field, with the gas and radiation to magnetic pressure ratio β ∼ 1, this makes the disk thermally stable, even though the radiation pressure strongly dominates over gas pressure. A significant part of the radiation emerging from the disk is captured by the black hole, so the disk is less luminous than a thin disk would be at the same accretion rate. Copyright © 2019, The Authors. All rights reserved.

关键词： Relativity

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Accretion tori around rotating neutron stars Paper I: Structure, shape and size

arXiv

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arXiv 2024年

作者： Matuszková, Monika Török, Gabriel Lančová, Debora Klimovičová, Kateřina Horák, Jiří Urbanec, Martin Šrámková, Eva Straub, Odele Urbancová, Gabriela Karas, Vladimír Research Centre for Computational Physics and Data Processing Institute of Physics Silesian University in Opava Bezručovo nám. 13 OpavaCZ-746 01 Czech Republic Astronomical Institute the Czech Academy of Sciences Boční II 1401 PragueCZ-14100 Czech Republic ORIGINS Excellence Cluster Boltzmannstr. 2 Garching85748 Germany Max Planck Institute for Extraterrestrial Physics Gießenbachstraße 1 Garching85748 Germany

We present a full general relativistic analytic solution for a radiation-pressure supported equilibrium fluid torus orbiting a rotating neutron star (NS). Previously developed analytical methods are thoroughly applied in the Hartle-Thorne geometry, including the effects of both the NS’s angular momentum and quadrupole moment. The structure, size and shape of the torus are explored, focusing especially on the critically thick solution – the cusp tori. For the astrophysically relevant range of NS parameters, we examine how our findings differ from those obtained for the Schwarzschild spacetime. The solutions for rotating stars display signatures of the interplay between relativistic and Newtonian effects where the impact of NS angular momentum and quadrupole moment are almost counterbalanced at the given radius. Nevertheless, the spacetime parameters still strongly influence the size of tori, which can be shown in a coordinate-independent way. Finally, we discuss the importance of the size of the central NS, determining whether or not the surrounding torus may exist. We provide a set of tools in a Wolfram Mathematica code, which poses a basis allowing for a further investigation of the impact of the NSs’ superdense matter equation of state on the spectral and temporal behaviour of accretion tori. © 2024, CC BY.

关键词： Neutrons

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