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Mass of the active galactic nucleus black hole XMMUJ134736.6+173403

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arXiv 2019年

作者： Goluchová, K. Török, G. Šrámková, E. Abramowicz, Marek A. Stuchlík, Z. Horák, Jiří Institute of Physics Research Centre for Computational Physics and Data Processing Research Centre for Theoretical Physics and Astrophysics Faculty of Philosophy & Science Silesian University in Opava Bezručovo nám. 13 OpavaCZ-746 01 Czech Republic Astronomical Institute Boční II 1401/2a Praha 4-SpořilovCZ-14131 Czech Republic

A recent study of the X-ray source XMMUJ134736.6+173403 has revealed a strong quasi-periodic modulation of the X-ray flux. The observation of two quasiperiodic oscillations (QPOs) that occur on a daily timescale and exhibit a 3:1 frequency ratio strongly supports the evidence for the presence of an active galactic nucleus black hole (AGN BH). Assuming an orbital origin of QPOs, we calculated the upper and lower limit on AGN BH mass M and found M ≈ 107 − 109 Mo. When we compare this to mass estimates of other sources, XMMUJ134736.6+173403 appears to be the most massive source with commensurable QPO frequencies, and its mass represents the current observational upper limit on AGN BH mass based on QPO observations. We note that it will be crucial for the falsification of particular resonance models of QPOs whether only a single QPO with a frequency that completes the harmonic sequence 3: 2: 1 is found in this source, or if a new different pair of QPOs with frequencies in the 3: 2 ratio is found. The former case would agree with the prediction of the 3: 2 epicyclic resonance model and BH mass M ≈ (5a2 + 8a + 8) × 107 Mo, where a is a dimensionless BH spin. Copyright © 2019, The Authors. All rights reserved.

关键词： Stars

Fundamental physics Opportunities with the Next-Generation Event Horizon Telescope

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arXiv 2023年

作者： Ayzenberg, Dimitry Blackburn, Lindy Brito, Richard Britzen, Silke Broderick, Avery E. Carballo-Rubio, Raúl Cardoso, Vitor Chael, Andrew Chatterjee, Koushik Chen, Yifan Cunha, Pedro V.P. Davoudiasl, Hooman Denton, Peter B. Doeleman, Sheperd S. Eichhorn, Astrid Eubanks, Marshall Fang, Yun Foschi, Arianna Fromm, Christian M. Galison, Peter Ghosh, Sushant G. Gold, Roman Gurvits, Leonid I. Hadar, Shahar Held, Aaron Houston, Janice Hu, Yichao Johnson, Michael D. Kocherlakota, Prashant Natarajan, Priyamvada Olivares, Héctor Palumbo, Daniel Pesce, Dominic W. Rajendran, Surjeet Roy, Rittick Saurabh Shao, Lijing Tahura, Shammi Tamar, Aditya Tiede, Paul Vincent, Frédéric H. Visinelli, Luca Wang, Zhiren Wielgus, Maciek Xue, Xiao Yakut, Kadri Yang, Huan Younsi, Ziri Theoretical Astrophysics Eberhard-Karls Universität Tübingen TübingenD-72076 Germany Center for Astrophysics Harvard & Smithsonian 60 Garden Street CambridgeMA02138 United States Harvard University 20 Garden Street CambridgeMA02138 United States CENTRA Departamento de Física Instituto Superior Técnico – IST Universidade de Lisboa – UL Avenida Rovisco Pais 1 Lisboa1049-001 Portugal Max-Planck-Institut für Radioastronomie Auf dem Hügel 69 BonnD-53121 Germany 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 CP3-Origins University of Southern Denmark Campusvej 55 Odense MDK-5230 Denmark Florida Space Institute University of Central Florida 12354 Research Parkway Partnership 1 OrlandoFL32826 United States Niels Bohr International Academy Niels Bohr Institute Blegdamsvej 17 Copenhagen2100 Denmark Princeton Gravity Initiative Jadwin Hall Princeton University PrincetonNJ08544 United States Department of Physics University of Maryland College ParkMD20742 United States Institute for Research in Electronics and Applied Physics University of Maryland College ParkMD20742 United States Harvard-Smithsonian Center for Astrophysics 60 Garden Street CambridgeMA02138 United States Campus de Santiago Aveiro3810-183 Portugal High Energy Theory Group Physics Department Brookhaven National Laboratory UptonNY11973 United States Asteroid Initiatives LLC United States Perimeter Institute for Theoretical Physics WaterlooONN2L2Y5 Canada Kavli Institute for Astronomy and Astrophysics Peking University Beijing100871 China Institut für Theoretische Physik und Astrophysik Universität Würzburg Emil-Fischer-Strasse 31 Würzburg97074 Germany Institut für Theoretische Physik Goethe Universität Frankfurt Max-von

The Event Horizon Telescope (EHT) Collaboration recently published the first images of the supermassive black holes in the cores of the Messier 87 and Milky Way galaxies. These observations have provided a new means to study supermassive black holes and probe physical processes occurring in the strong-field regime. We review the prospects of future observations and theoretical studies of supermassive black hole systems with the next-generation Event Horizon Telescope (ngEHT), which will greatly enhance the capabilities of the existing EHT array. These enhancements will open up several previously inaccessible avenues of investigation, thereby providing important new insights into the properties of supermassive black holes and their environments. This review describes the current state of knowledge for five key science cases, summarising the unique challenges and opportunities for fundamental physics investigations that the ngEHT will enable. Copyright © 2023, The Authors. All rights reserved.

关键词： Telescopes

Little impact of mergers and galaxy morphology on the production and escape of ionizing photons in the early Universe

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arXiv 2025年

作者： Mascia, S. Pentericci, L. Llerena, M. Calabrò, A. Matthee, J. Flury, S. Pacucci, F. Jaskot, A. Amorín, R.O. Bhatawdekar, R. Castellano, M. Cleri, N. Costantin, L. Davis, K. Di Cesare, C. Dickinson, M. Fontana, A. Guo, Y. Giavalisco, M. Holwerda, B.W. Hu, W. Huertas-Company, M. Jung, Intae Kartaltepe, J. Kashino, D. Koekemoer, Anton M. Lucas, R.A. Lotz, J. Napolitano, L. Jogee, S. Wilkins, S. INAF – Osservatorio Astronomico di Roma via Frascati 33 Monteporzio Catone00078 Italy Am Campus 1 KlosterneuburgA-3400 Austria Institute for Astronomy University of Edinburgh Royal Observatory EdinburghEH9 3HJ United Kingdom Center for Astrophysics Harvard & Smithsonian CambridgeMA02138 United States Department of Physics and Astronomy Williams College WilliamstownMA01267 United States Apartado 3004 Granada18080 Spain Camino Bajo del Castillo s/n Villanueva de la Cañada Madrid28692 Spain Department of Astronomy and Astrophysics The Pennsylvania State University University Park PA16802 United States Institute for Computational and Data Sciences The Pennsylvania State University University Park PA16802 United States Institute for Gravitation and the Cosmos The Pennsylvania State University University Park PA16802 United States Centro de Astrobiología Consejo Superior de Investigaciones Científicas Madrid Spain Department of Physics Unit 3046 University of Connecticut 196A Auditorium Road StorrsCT06269 United States University of Massachusetts Amherst 710 North Pleasant Street AmherstMA01003-9305 United States NSF’s National Optical-Infrared Astronomy Research Laboratory 950 N. Cherry Ave. TucsonAZ85719 United States University of Louisville Department of Physics and Astronomy 102 Natural Science Building LouisvilleKY40292 United States Department of Physics and Astronomy Texas A&M University College StationTX77843-4242 United States George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy Texas A&M University College StationTX United States Instituto de Astrofísica de Canarias C/Vía Láctea s/n La Laguna Spain Space Telescope Science Institute 3700 San Martin Drive BaltimoreMD21218 United States Laboratory for Multiwavelength Astrophysics School of Physics and Astronomy Rochester Institute of Technology 84 Lomb Memorial Drive RochesterNY14623 United States National Astronomical Observatory

Compact, star-forming galaxies with high star formation rate surface densities (ΣSFR) are often efficient Lyman continuum (LyC) emitters at z ≤ 4.5, likely as intense stellar feedback creates low-density channels that allow photons to escape. Irregular or disturbed morphologies, such as those resulting from mergers, can also facilitate LyC escape by creating anisotropic gas distributions. We investigate the influence of galaxy morphology on LyC production and escape at redshifts 5 ≤ z ≤ 7 using observations from various James Webb Space Telescope (JWST) surveys. Our sample consists of 436 sources, which are predominantly low-mass (∼ 108.15M☉), star-forming galaxies with ionizing photon efficiency (ξion) values consistent with canonical expectations. Since direct measurements of fesc are not possible during the Epoch of Reionization (EoR), we predict fesc for high-redshift galaxies by applying survival analysis to a subsample of LyC emitters from the Low-Redshift Lyman Continuum Survey (LzLCS), selected to be direct analogs of reionization-era galaxies. We find that these galaxies exhibit on average modest predicted escape fractions (∼ 0.04). Additionally, we assess the correlation between morphological features and LyC emission. Our findings indicate that neither ξion nor the predicted fesc values show a significant correlation with the presence of merger signatures. This suggests that in low-mass galaxies at z ≥ 5, strong morphological disturbances are not the primary mechanism driving LyC emission and leakage. Instead, compactness and star formation activity likely play a more pivotal role in regulating LyC escape. Copyright © 2025, The Authors. All rights reserved.

关键词： Photons

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

Disks in Nearby Young Stellar Associations Found Via Virtual Reality

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arXiv 2022年

作者： Higashio, Susan Kuchner, Marc J. Silverberg, Steven M. Brandt, Matthew A. Grubb, Thomas G. Gagné, Jonathan Debes, John H. Schlieder, Joshua Wisniewski, John P. Slocum, Stewart Bans, Alissa S. Bhattacharjee, Shambo Biggs, Joseph R. Bosch, Milton K.D. Cernohous, Tadeas Doll, Katharina Luca, Hugo A. Durantini Enachioaie, Alexandru Griffith, Phillip Hamilton, Joshua Holden, Jonathan Hyogo, Michiharu Jung, Dawoon Lau, Lily Piñeiro, Fernanda Piipuu, Art Stiller, Lisa Nasa Goddard Space Flight Center Exoplanets and Stellar Astrophysics Laboratory Code 667 GreenbeltMD20771 United States Center for Research and Exploration in Space Science and Technology NASA/GSFC GreenbeltMD20771 United States Mit Kavli Institute United States Nasa Goddard Space Flight Center Science Data Processing Branch Code 587 GreenbeltMD20771 United States Planétarium Rio Tinto Alcan Espace Pour la Vie 4801 av. Pierre-de Coubertin MontrealQC Canada Institute for Research on Exoplanets Université de Montréal Département de Physique C.P. 6128 Succ. Centre-ville MontrealQCH3C 3J7 Canada Space Telescope Science Institute 3700 San Martin Dr. BaltimoreMD21218 United States Homer L. Dodge Department of Physics and Astronomy University of Oklahoma 440 W. Brooks Street NormanOK73019 United States Department of Computer Science Johns Hopkins University United States Department of Physics Emory University 201 Dowman Drive AtlantaGA30322 United States French National Centre for Scientific Research France Disk Detective IATE-OAC Universidad Nacional de Córdoba-CONICET Laprida 854 CórdobaX5000 BGR Argentina Meisei University 2-1-1 Hodokubo Tokyo Hino191-0042 Japan

The Disk Detective citizen science project recently released a new catalog of disk candidates found by visual inspection of images from NASA's Wide-Field Infrared Survey Explorer (WISE) mission and other surveys. We applied this new catalog of well-vetted disk candidates to search for new members of nearby young stellar associations (YSAs) using a novel technique based on Gaia data and virtual reality (VR). We examined AB Doradus, Argus, β Pictoris, Carina, Columba, Octans-Near, TucanaHorologium, and TW Hya by displaying them in VR together with other nearby stars, color-coded to show infrared excesses found via Disk Detective. Using this method allows us to find new association members in mass regimes where isochrones are degenerate. We propose ten new YSA members with infrared excesses: three of AB Doradus (HD 44775, HD 40540 and HD 44510), one of β Pictoris (HD 198472), two of Octans-Near (HD 157165 and BD+35 2953), and four disk-hosting members of a combined population of Carina, Columba and Tucana-Horologium: CPD-57 937, HD 274311, HD 41992, and WISEA J092521.90-673224.8. This last object (J0925) appears to be an extreme debris disk with a fractional infrared luminosity of 3.7 × 10-2. We also propose two new members of AB Doradus that do not show infrared excesses: TYC 6518-1857-1 and CPD-25 1292. We find HD 15115 appears to be a member of Tucana-Horologium rather than β Pictoris. We advocate for membership in Columba-Carina of HD 30447, CPD-35 525, and HD 35841. Finally, we propose that three M dwarfs, previously considered members of Tuc-Hor are better considered a separate association, tentatively called "Smethells 165". © 2022, CC BY.

关键词： Stars

The first JWST spectrum of a GRB afterglow: No bright supernova in observations of the brightest GRB of all time, GRB 221009A

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arXiv 2023年

作者： Levan, A.J. Lamb, G.P. Schneider, B. Hjorth, J. Zafar, T. Postigo, A. de Ugarte Sargent, B. Mullally, S.E. Izzo, L. D’Avanzo, P. Burns, E. Fernández, J.F. Agüí Barclay, T. Bernardini, M.G. Bhirombhakdi, K. Bremer, M. Brivio, R. Campana, S. Chrimes, A.A. D’Elia, V. Della Valle, M. De Pasquale, M. Ferro, M. Fong, W. Fruchter, A.S. Fynbo, J.P.U. Gaspari, N. Gompertz, B.P. Hartmann, D.H. Hedges, C.L. Heintz, K.E. Hotokezaka, K. Jakobsson, P. Kann, D.A. Kennea, J.A. Laskar, T. Floc’h, E. Le Malesani, D.B. Melandri, A. Metzger, B.D. Oates, S.R. Pian, E. Piranomonte, S. Pugliese, G. Racusin, J.L. Rastinejad, J.C. Ravasio, M.E. Rossi, A. Saccardi, A. Salvaterra, R. Sbarufatti, B. Starling, R.L.C. Tanvir, N.R. Thöne, C.C. van der Horst, A.J. Vergani, S.D. Watson, D. Wiersema, K. Wijers, R.A.M.J. Xu, Dong Department of Astrophysics IMAPP Radboud University Nijmegen6525 AJ Netherlands Department of Physics University of Warwick CoventryCV4 7AL United Kingdom Astrophysics Research Institute Liverpool John Moores University 146 Brownlow Hill LiverpoolL3 5RF United Kingdom Kavli Institute for Astrophysics and Space Research Massachusetts Institute of Technology 77 Massachusetts Ave CambridgeMA02139 United States DARK Niels Bohr Institute University of Copenhagen Jagtvej 128 Copenhagen2200 Denmark Australian Astronomical Optics Macquarie University 105 Delhi Road North RydeNSW2113 Australia Artemis Université Côte d’Azur Observatoire de la Côte d’Azur CNRS NiceF-06304 France Space Telescope Science Institute 3700 San Martin Drive BaltimoreMD21218 United States Center for Astrophysical Sciences The William H. Miller III Department of Physics and Astronomy Johns Hopkins University BaltimoreMD21218 United States INAF Osservatorio Astronomico di Brera Via E. Bianchi 46 LC MerateI-23807 Italy Department of Physics and Astronomy Louisiana State University Baton RougeLA70803 United States Instituto de Astrofísica de Andalucía CSIC Glorieta de la Astronomía s/n Granada18008 Spain NASA Goddard Space Flight Center GreenbeltMD20771 United States University of Maryland Baltimore County BaltimoreMD21250 United States 300 Rue de la Piscine Saint Martin d’HèresF-38406 France Universitá degli Studi dell’Insubria Dipartimento di Scienza e Alta Tecnologia via Valleggio 11 Como22100 Italy ASI Italian Space Agency Space Science Data Centre Via del Politecnico snc Rome00133 Italy Monte Porzio CatoneI-00040 Italy Capodimonte Astronomical Observatory INAF-Napoli Salita Moiariello 16 NapoliI-80131 Italy University of Messina Mathematics Informatics Physics and Earth Science Department Via F.D. D’Alcontres 31 Polo Papardo Messina98166 Italy Department of Physics and Astronomy Northwestern University EvanstonIL60208 United States T

We present JWST and Hubble Space Telescope (HST) observations of the afterglow of GRB 221009A, the brightest gamma-ray burst (GRB) ever observed. This includes the first mid-IR spectra of any GRB, obtained with JWST/NIRSPEC (0.6-5.5 micron) and MIRI (5-12 micron), 12 days after the burst. Assuming that the intrinsic spectral slope is a single power-law, with Fν ∝ ν−β, we obtain β ≈ 0.35, modified by substantial dust extinction with AV = 4.9. This suggests extinction above the notional Galactic value, possibly due to patchy extinction within the Milky Way or dust in the GRB host galaxy. It further implies that the X-ray and optical/IR regimes are not on the same segment of the synchrotron spectrum of the afterglow. If the cooling break lies between the X-ray and optical/IR, then the temporal decay rates would only match a post jet-break model, with electron index p Copyright © 2023, The Authors. All rights reserved.

关键词： Supernovae

Correction: An electrodeposited superaerophobic nickel catalyst on pencil-drawn paper: a novel approach for highly efficient and stable hydrogen evolution

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Inorganic Chemistry Frontiers 2024年第12期11卷 3654-3654页

作者： Qian Sun Xiaoyu Hao Tianyi Zhang Zelin Ma Kui Hu Ming Yang Xiaolei Huang Xuqing Liu State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal Materials Northwestern Polytechnical University Xi'an Shaanxi 710072 P. R. China Department of Chemistry University of Manchester Manchester UK Department of Applied Physics The Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong SAR China Research Centre on Data Sciences & Artificial Intelligence The Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong SAR China Institute of Material and Chemistry Ganjiang Innovation Academy Chinese Academy of Sciences Ganzhou China Shandong Laboratory of Yantai Advanced Materials and Green Manufacture Yantai China

Correction for ‘An electrodeposited superaerophobic nickel catalyst on pencil-drawn paper: a novel approach for highly efficient and stable hydrogen evolution’ by Qian Sun et al., Inorg. Chem. Front., 2024, https://...

Correction for ‘An electrodeposited superaerophobic nickel catalyst on pencil-drawn paper: a novel approach for highly efficient and stable hydrogen evolution’ by Qian Sun et al., Inorg. Chem. Front., 2024, https://***/10.1039/D4QI00101J.

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Reflection-asymmetric wormholes and their double shadows

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arXiv 2020年

作者： Wielgus, Maciek Horák, Jiří Vincent, Frederic Abramowicz, Marek Black Hole Initiative at Harvard University 20 Garden Street CambridgeMA02138 United States Center for Astrophysics Harvard & Smithsonian 60 Garden Street CambridgeMA02138 United States Astronomical Institute Academy of Sciences Bočni II 1401 PragueCZ-14131 Czech Republic LESIA Observatoire de Paris Université PSL CNRS Sorbonne Universités UPMC Univ. Paris 06 Univ. de Paris Sorbonne Paris Cité 5 place Jules Janssen Meudon92195 France Nicolaus Copernicus Astronomical Centre Polish Academy of Sciences Bartycka 18 Warsaw00-716 Poland Research Center for Computational Physics and Data Processing Institute of Physics Silesian University in Opava Czech Republic Department of Physics Göteborg University Sweden

We discuss construction and observational properties of wormholes obtained by connecting two Reissner–Nordström spacetimes with distinct mass and charge parameters. These objects are spherically symmetric, but not reflection-symmetric, as the connected spacetimes differ. The reflection-asymmetric wormholes may reflect a significant fraction of the infalling radiation back to the spacetime of its origin. We interpret this effect in a simple framework of the effective photon potential. Depending on the model parameters, image of such a wormhole seen by a distant observer (its "shadow") may contain a photon ring formed on the observer’s side, photon ring formed on the other side of the wormhole, or both photon rings. These unique topological features would allow us to firmly distinguish this class of objects from black holes using radioastronomical observations. Copyright © 2020, The Authors. All rights reserved.

关键词： Photons

A binary tree approach to template placement for searches for gravitational waves from compact binary mergers

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arXiv 2022年

作者： Hanna, Chad Kennington, James Sakon, Shio Privitera, Stephen Fernandez, Miguel Wang, Jonathan Messick, Cody Pace, Alex Cannon, Kipp Joshi, Prathamesh Huxford, Rachael Caudill, Sarah Chan, Chiwai Cousins, Bryce Creighton, Jolien D.E. Ewing, Becca Fong, Heather Godwin, Patrick Magee, Ryan Meacher, Duncan Morisaki, Soichiro Mukherjee, Debnandini Ohta, Hiroaki Sachdev, Surabhi Singh, Divya Tapia, Ron Tsukada, Leo Tsuna, Daichi Tsutsui, Takuya Ueno, Koh Viets, Aaron Wade, Leslie Wade, Madeline Department of Physics The Pennsylvania State University University ParkPA16802 United States Institute for Gravitation and the Cosmos The Pennsylvania State University University ParkPA16802 United States Department of Astronomy and Astrophysics The Pennsylvania State University University ParkPA16802 United States Institute for Computational and Data Sciences The Pennsylvania State University University ParkPA16802 United States Albert-Einstein-Institut Max-Planck-Institut für Gravitationsphysik Potsdam-GolmD-14476 Germany Department of Physics University of Michigan Ann ArborMI48109 United States RESCEU The University of Tokyo Tokyo113-0033 Japan Nikhef Science Park Amsterdam1098 XG Netherlands Leonard E. Parker Center for Gravitation Cosmology and Astrophysics University of Wisconsin-Milwaukee MilwaukeeWI53201 United States Graduate School of Science The University of Tokyo Tokyo113-0033 Japan Institute for Cosmic Ray Research The University of Tokyo 5-1-5 Kashiwanoha Chiba Kashiwa277-8582 Japan LIGO Laboratory California Institute of Technology MS 100-36 PasadenaCA91125 United States Department of Physics Hayes Hall Kenyon College GambierOH43022 United States

We demonstrate a new geometric method for fast template placement for searches for gravitational waves from the inspiral, merger and ringdown of compact binaries. The method is based on a binary tree decomposition of the template bank parameter space into non-overlapping hypercubes. We use a numerical approximation of the signal overlap metric at the center of each hypercube to estimate the number of templates required to cover the hypercube and determine whether to further split the hypercube. As long as the expected number of templates in a given cube is greater than a given threshold, we split the cube along its longest edge according to the metric. When the expected number of templates in a given hypercube drops below this threshold, the splitting stops and a template is placed at the center of the hypercube. Using this method, we generate aligned-spin template banks covering the mass range suitable for a search of Advanced LIGO data. The aligned-spin bank required ∼ 24 CPU-hours and produced 2 million templates. In general, we find that other methods, namely stochastic placement, produces a more strictly bounded loss in match between waveforms, with the same minimal match between waveforms requiring about twice as many templates with our proposed algorithm. Though we note that the average match is higher, which would lead to a higher detection efficiency. Our primary motivation is not to strictly minimize the number of templates with this algorithm, but rather to produce a bank with useful geometric properties in the physical parameter space coordinates. Such properties are useful for population modeling and parameter estimation. Copyright © 2022, The Authors. All rights reserved.

关键词： Gravity waves