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Joint analysis of Dark Energy Survey Year 3 data and CMB lensing from SPT and Planck. I. Construction of CMB lensing maps and modeling choices

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Physical Review D 2023年第2期107卷 023529-023529页

作者： Y. Omori E. J. Baxter C. Chang O. Friedrich A. Alarcon O. Alves A. Amon F. Andrade-Oliveira K. Bechtol M. R. Becker G. M. Bernstein J. Blazek L. E. Bleem H. Camacho A. Campos A. Carnero Rosell M. Carrasco Kind R. Cawthon R. Chen A. Choi J. Cordero T. M. Crawford M. Crocce C. Davis J. DeRose S. Dodelson C. Doux A. Drlica-Wagner K. Eckert T. F. Eifler F. Elsner J. Elvin-Poole S. Everett X. Fang A. Ferté P. Fosalba M. Gatti G. Giannini D. Gruen R. A. Gruendl I. Harrison K. Herner H. Huang E. M. Huff D. Huterer M. Jarvis E. Krause N. Kuropatkin P.-F. Leget P. Lemos A. R. Liddle N. MacCrann J. McCullough J. Muir J. Myles A. Navarro-Alsina S. Pandey Y. Park A. Porredon J. Prat M. Raveri R. P. Rollins A. Roodman R. Rosenfeld A. J. Ross E. S. Rykoff C. Sánchez J. Sanchez L. F. Secco I. Sevilla-Noarbe E. Sheldon T. Shin M. A. Troxel I. Tutusaus T. N. Varga N. Weaverdyck R. H. Wechsler W. L. K. Wu B. Yanny B. Yin Y. Zhang J. Zuntz T. M. C. Abbott M. Aguena S. Allam J. Annis D. Bacon B. A. Benson E. Bertin S. Bocquet D. Brooks D. L. Burke J. E. Carlstrom J. Carretero C. L. Chang R. Chown M. Costanzi L. N. da Costa A. T. Crites M. E. S. Pereira T. de Haan J. De Vicente S. Desai H. T. Diehl M. A. Dobbs P. Doel W. Everett I. Ferrero B. Flaugher D. Friedel J. Frieman J. García-Bellido E. Gaztanaga E. M. George T. Giannantonio N. W. Halverson S. R. Hinton G. P. Holder D. L. Hollowood W. L. Holzapfel K. Honscheid J. D. Hrubes D. J. James L. Knox K. Kuehn O. Lahav A. T. Lee M. Lima D. Luong-Van M. March J. J. McMahon P. Melchior F. Menanteau S. S. Meyer R. Miquel L. Mocanu J. J. Mohr R. Morgan T. Natoli S. Padin A. Palmese F. Paz-Chinchón A. Pieres A. A. Plazas Malagón C. Pryke C. L. Reichardt A. K. Romer J. E. Ruhl E. Sanchez K. K. Schaffer M. Schubnell S. Serrano E. Shirokoff M. Smith Z. Staniszewski A. A. Stark E. Suchyta G. Tarle D. Thomas C. To J. D. Vieira J. Weller R. Williamson Department of Astronomy and Astrophysics University of Chicago Chicago Illinois 60637 USA Kavli Institute for Cosmological Physics University of Chicago Chicago Illinois 60637 USA Department of Physics Stanford University 382 Via Pueblo Mall Stanford California 94305 USA Kavli Institute for Particle Astrophysics and Cosmology P. O. Box 2450 Stanford University Stanford California 94305 USA Institute for Astronomy University of Hawai’i 2680 Woodlawn Drive Honolulu Hawaii 96822 USA Kavli Institute for Cosmology University of Cambridge Madingley Road Cambridge CB3 0HA United Kingdom Argonne National Laboratory 9700 South Cass Avenue Lemont Illinois 60439 USA Department of Physics University of Michigan Ann Arbor Michigan 48109 USA Laboratório Interinstitucional de e-Astronomia - LIneA Rua Gal. José Cristino 77 Rio de Janeiro RJ 20921-400 Brazil Physics Department 2320 Chamberlin Hall University of Wisconsin-Madison 1150 University Avenue Madison Wisconsin 53706-1390 USA Department of Physics and Astronomy University of Pennsylvania Philadelphia Pennsylvania 19104 USA Department of Physics Northeastern University Boston Massachusetts 02115 USA Laboratory of Astrophysics École Polytechnique Fédérale de Lausanne (EPFL) Observatoire de Sauverny 1290 Versoix Switzerland High-Energy Physics Division Argonne National Laboratory 9700 South Cass Avenue. Argonne Illinois 60439 USA Instituto de Física Teórica Universidade Estadual Paulista São Paulo 01140-070 Brazil Department of Physics Carnegie Mellon University Pittsburgh Pennsylvania 15312 USA Instituto de Astrofisica de Canarias E-38205 La Laguna Tenerife Spain Universidad de La Laguna Departamento Astrofísica E-38206 La Laguna Tenerife Spain Center for Astrophysical Surveys National Center for Supercomputing Applications 1205 West Clark Street Urbana Illinois 61801 USA Department of Astronomy University of Illinois at Urbana-Champaign 1002 W. Green Street Urbana Illinois 61801 USA Physic

Joint analyses of cross-correlations between measurements of galaxy positions, galaxy lensing, and lensing of the cosmic microwave background (CMB) offer powerful constraints on the large-scale structure of the Universe. In a forthcoming analysis, we will present cosmological constraints from the analysis of such cross-correlations measured using Year 3 data from the Dark Energy Survey (DES), and CMB data from the South Pole Telescope (SPT) and Planck. Here we present two key ingredients of this analysis: (1) an improved CMB lensing map in the SPT-SZ survey footprint and (2) the analysis methodology that will be used to extract cosmological information from the cross-correlation measurements. Relative to previous lensing maps made from the same CMB observations, we have implemented techniques to remove contamination from the thermal Sunyaev Zel’dovich effect, enabling the extraction of cosmological information from smaller angular scales of the cross-correlation measurements than in previous analyses with DES Year 1 data. We describe our model for the cross-correlations between these maps and DES data, and validate our modeling choices to demonstrate the robustness of our analysis. We then forecast the expected cosmological constraints from the galaxy survey-CMB lensing auto and cross-correlations. We find that the galaxy-CMB lensing and galaxy shear-CMB lensing correlations will on their own provide a constraint on S8=σ8Ωm/0.3 at the few percent level, providing a powerful consistency check for the DES-only constraints. We explore scenarios where external priors on shear calibration are removed, finding that the joint analysis of CMB lensing cross-correlations can provide constraints on the shear calibration amplitude at the 5% to 10% level.

关键词： Cosmic microwave background Cosmological parameters Dark matter Evolution of the Universe Gravitational lenses Large scale structure of the Universe

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Joint analysis of Dark Energy Survey Year 3 data and CMB lensing from SPT and Planck. II. Cross-correlation measurements and cosmological constraints

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Physical Review D 2023年第2期107卷 023530-023530页

作者： C. Chang Y. Omori E. J. Baxter C. Doux A. Choi S. Pandey A. Alarcon O. Alves A. Amon F. Andrade-Oliveira K. Bechtol M. R. Becker G. M. Bernstein F. Bianchini J. Blazek L. E. Bleem H. Camacho A. Campos A. Carnero Rosell M. Carrasco Kind R. Cawthon R. Chen J. Cordero T. M. Crawford M. Crocce C. Davis J. DeRose S. Dodelson A. Drlica-Wagner K. Eckert T. F. Eifler F. Elsner J. Elvin-Poole S. Everett X. Fang A. Ferté P. Fosalba O. Friedrich M. Gatti G. Giannini D. Gruen R. A. Gruendl I. Harrison K. Herner H. Huang E. M. Huff D. Huterer M. Jarvis A. Kovacs E. Krause N. Kuropatkin P.-F. Leget P. Lemos A. R. Liddle N. MacCrann J. McCullough J. Muir J. Myles A. Navarro-Alsina Y. Park A. Porredon J. Prat M. Raveri R. P. Rollins A. Roodman R. Rosenfeld A. J. Ross E. S. Rykoff C. Sánchez J. Sanchez L. F. Secco I. Sevilla-Noarbe E. Sheldon T. Shin M. A. Troxel I. Tutusaus T. N. Varga N. Weaverdyck R. H. Wechsler W. L. K. Wu B. Yanny B. Yin Y. Zhang J. Zuntz T. M. C. Abbott M. Aguena S. Allam J. Annis D. Bacon B. A. Benson E. Bertin S. Bocquet D. Brooks D. L. Burke J. E. Carlstrom J. Carretero C. L. Chang R. Chown M. Costanzi L. N. da Costa A. T. Crites M. E. S. Pereira T. de Haan J. De Vicente S. Desai H. T. Diehl M. A. Dobbs P. Doel W. Everett I. Ferrero B. Flaugher D. Friedel J. Frieman J. García-Bellido E. Gaztanaga E. M. George T. Giannantonio N. W. Halverson S. R. Hinton G. P. Holder D. L. Hollowood W. L. Holzapfel K. Honscheid J. D. Hrubes D. J. James L. Knox K. Kuehn O. Lahav A. T. Lee M. Lima D. Luong-Van M. March J. J. McMahon P. Melchior F. Menanteau S. S. Meyer R. Miquel L. Mocanu J. J. Mohr R. Morgan T. Natoli S. Padin A. Palmese F. Paz-Chinchón A. Pieres A. A. Plazas Malagón C. Pryke C. L. Reichardt M. Rodríguez-Monroy A. K. Romer J. E. Ruhl E. Sanchez K. K. Schaffer M. Schubnell S. Serrano E. Shirokoff M. Smith Z. Staniszewski A. A. Stark E. Suchyta G. Tarle D. Thomas C. To J. D. Vieira J. Weller R. Williamson Department of Astronomy and Astrophysics University of Chicago Chicago Illinois 60637 USA Kavli Institute for Cosmological Physics University of Chicago Chicago Illinois 60637 USA Department of Physics Stanford University 382 Via Pueblo Mall Stanford California 94305 USA Kavli Institute for Particle Astrophysics & Cosmology P. O. Box 2450 Stanford University Stanford California 94305 USA Institute for Astronomy University of Hawai‘i 2680 Woodlawn Drive Honolulu Hawaii 96822 USA Department of Physics and Astronomy University of Pennsylvania Philadelphia Pennsylvania 19104 USA California Institute of Technology 1200 East California Blvd MC 249-17 Pasadena California 91125 USA Argonne National Laboratory 9700 South Cass Avenue Lemont Illinois 60439 USA Department of Physics University of Michigan Ann Arbor Michigan 48109 USA Laboratório Interinstitucional de e-Astronomia - LIneA Rua Gal. José Cristino 77 Rio de Janeiro RJ - 20921-400 Brazil Physics Department 2320 Chamberlin Hall University of Wisconsin-Madison 1150 University Avenue Madison Wisconsin 53706-1390 School of Physics University of Melbourne Parkville Victoria 3010 Australia Department of Physics Northeastern University Boston Massachusetts 02115 USA Laboratory of Astrophysics École Polytechnique Fédérale de Lausanne (EPFL) Observatoire de Sauverny 1290 Versoix Switzerland Instituto de Física Teórica Universidade Estadual Paulista São Paulo Brazil Department of Physics Carnegie Mellon University Pittsburgh Pennsylvania 15312 USA Instituto de Astrofisica de Canarias E-38205 La Laguna Tenerife Spain Universidad de La Laguna Dpto. Astrofísica E-38206 La Laguna Tenerife Spain Center for Astrophysical Surveys National Center for Supercomputing Applications 1205 West Clark St. Urbana Illinois 61801 USA Department of Astronomy University of Illinois at Urbana-Champaign 1002 W. Green Street Urbana Illinois 61801 USA Physics Department William Jewell College Liberty Missouri 6

Cross-correlations of galaxy positions and galaxy shears with maps of gravitational lensing of the cosmic microwave background (CMB) are sensitive to the distribution of large-scale structure in the Universe. Such cross-correlations are also expected to be immune to some of the systematic effects that complicate correlation measurements internal to galaxy surveys. We present measurements and modeling of the cross-correlations between galaxy positions and galaxy lensing measured in the first three years of data from the Dark Energy Survey with CMB lensing maps derived from a combination of data from the 2500 deg2 SPT-SZ survey conducted with the South Pole Telescope and full-sky data from the Planck satellite. The CMB lensing maps used in this analysis have been constructed in a way that minimizes biases from the thermal Sunyaev Zel’dovich effect, making them well suited for cross-correlation studies. The total signal-to-noise of the cross-correlation measurements is 23.9 (25.7) when using a choice of angular scales optimized for a linear (nonlinear) galaxy bias model. We use the cross-correlation measurements to obtain constraints on cosmological parameters. For our fiducial galaxy sample, which consist of four bins of magnitude-selected galaxies, we find constraints of Ωm=0.272−0.052+0.032 and S8≡σ8Ωm/0.3=0.736−0.028+0.032 (Ωm=0.245−0.044+0.026 and S8=0.734−0.028+0.035) when assuming linear (nonlinear) galaxy bias in our modeling. Considering only the cross-correlation of galaxy shear with CMB lensing, we find Ωm=0.270−0.061+0.043 and S8=0.740−0.029+0.034. Our constraints on S8 are consistent with recent cosmic shear measurements, but lower than the values preferred by primary CMB measurements from Planck.

关键词： Cosmic microwave background Cosmological parameters Large scale structure of the Universe

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INTRODUCTION

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Bulletin of the American Meteorological Society 2024年第8期105卷 S1-S11页

作者： Boyer, T. Blunden, J. Dunn, R.J.H. NOAA/NESDIS National Centers for Environmental Information Silver Spring Maryland NOAA/NESDIS National Centers for Environmental Information Asheville North Carolina Met Office Hadley Centre Exeter United Kingdom European Centre for Medium-Range Weather Forecasts Reading United Kingdom University of Maryland College Park Maryland Scripps Institution of Oceanography University of California San Diego La Jolla California NOAA/NWS National Centers for Environmental Prediction Climate Prediction Center College Park Maryland Brandenburg University of Technology (BTU) Cottbus-Senftenberg Germany Servicio Meteorológico Nacional Buenos Aires Argentina NOAA/OAR Physical Sciences Laboratory Boulder Colorado European Centre for Medium-Range Weather Forecasts Bonn Germany Center for Geophysical Research and School of Physics University of Costa Rica San José Costa Rica Department of Meteorology and National Centre for Earth Observation University of Reading Reading United Kingdom Centro Nacional de Monitoramento e Alertas de Desastres Naturais CEMADEN São Paulo Brazil Université Grenoble Alpes Institut des Géosciences de l’Environnement IRD CNRS Grenoble INP Grenoble France Hampton University Hampton Virginia Seychelles Meteorological Authority Mahe Seychelles Section for Glaciers Ice and Snow Norwegian Water Resources and Energy Directorate Oslo Norway National Research Institute for Agriculture Food and Environment (INRAE) CARRTEL Université Savoie Mont Blanc Thonon les Bains France Graduate School of Agriculture Osaka Metropolitan University Sakai Japan Science Faculty Universidad Nacional de Colombia Bogotá Colombia University of Bremen Bremen Germany NOAA Global Monitoring Laboratory Boulder Colorado Servicio Nacional de Meteorología e Hidrología del Perú Lima Perú Centro de Investigaciones sobre Desertificación – Spanish National Research Council (CSIC-UV-GVA) Valencia Spain Hydro-Climate Extremes Lab (H-CEL) Ghent University Ghent Belgium Department o

In 2023, La Niña conditions that generally prevailed in the eastern Pacific Ocean from mid-2020 into early 2023 gave way to a strong El Niño by October. Atmospheric concentrations of Earth’s major greenhouse gases—carbon dioxide, methane, and nitrous oxide—all increased to record-high levels. The annual global average carbon dioxide concentration in the atmosphere rose to 419.3±0.1 ppm, which is 50% greater than the pre-industrial level. The growth from 2022 to 2023 was 2.8 ppm, the fourth highest in the record since the 1960s. The combined short-term effects of El Niño and the long-term effects of increasing levels of heat-trapping gases in the atmosphere contributed to new records for many essential climate variables reported here. The annual global temperature across land and oceans was the highest in records dating as far back as 1850, with the last seven months (June–December) having each been record warm. Over land, the globally averaged temperature was also record high. Dozens of countries reported record or near-record warmth for the year, including China and continental Europe as a whole (warmest on record), India and Russia (second warmest), and Canada (third warmest). Intense and widespread heatwaves were reported around the world. In Vietnam, an all-time national maximum temperature record of 44.2°C was observed at Tuong Duong on 7 May, surpassing the previous record of 43.4°C at Huong Khe on 20 April 2019. In Brazil, the air temperature reached 44.8°C in Araçuaí in Minas Gerais on 20 November, potentially a new national record and 12.8°C above normal. The effect of rising temperatures was apparent in the cryosphere, where snow cover extent by June 2023 was the smallest in the 56-year record for North America and seventh smallest for the Northern Hemisphere overall. Heatwaves contributed to the greatest average mass balance loss for Alpine glaciers around the world since the start of the record in 1970. Due to rapid volume loss beginning in 2021, St. A

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Analysis of potential bioethanol production from pineapple (Ananas Comosus L. Merr) peel waste Belik District - Pemalang - Central Java

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AIP Conference Proceedings 2020年第1期2296卷

作者： E. Hugeng Wandono Endang Kusdiyantini Hadiyanto 1Magister Program of Energy School of Postgraduate Studies Diponegoro University Jl. Imam Bardjo SH No.5 Pleburan Semarang 50241 Indonesia 2Department of Biology Faculty of Science and Mathematics Diponegoro University Jl. Prof. Soedharto SH Tembalang Semarang 50275 Indonesia 3Department of Chemical Engineering Faculty of Engineering Diponegoro University Jl. Prof. Soedharto SH Tembalang Semarang 50275 Indonesia

Belik Subdistrict - Pemalang District, which produces honey pineapple with a contribution of around 27,162 tons per year in Central Java, is a superior product, which has great and reliable potential to develop the regional economy. It several small and medium-sized businesses that produce processed pineapple honey that is made into pineapple juice products, pineapple chips, pineapple meal, and some small and medium businesses that sell pineapples peel. This activity produces a lot of honey pineapples peel waste; utilization of pineapple peel waste into bioethanol is expected to be potential energy for household needs. Pineapple skin waste containing carbohydrates and reducing sugars is high enough so that it has the potential to become bioethanol by carrying out the process of fermentation and distillation. One kilogram of pineapple fruit can produce 250 grams of pineapple peel waste, or 1 ton can produce about 250 kg of peel waste. This study uses raw materials for pineapple skin waste with LSF (liquid state fermentation) fermentation method and the distillation process. Using 2.5 kg of peel can produce 1 liter of bioethanol with 27% content. In Belik District, produces pineapple peel waste around 4,125 tons (4,125 kg) per day, bioethanol can be produced around 1.650 liters per day.

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Polarimetric geometric modeling for mm-VLBI observations of black holes

arXiv

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arXiv 2023年

作者： Roelofs, Freek Johnson, Michael D. Chael, Andrew Janssen, Michael Wielgus, Maciek Broderick, Avery E. Akiyama, Kazunori Alberdi, Antxon Alef, Walter Algaba, Juan Carlos Anantua, Richard Asada, Keiichi Azulay, Rebecca Bach, Uwe Baczko, Anne-Kathrin Ball, David Baloković, Mislav Barrett, John Bauböck, Michi Benson, Bradford A. Bintley, Dan Blackburn, Lindy Blundell, Raymond Bouman, Katherine L. Bower, Geoffrey C. Boyce, Hope Bremer, Michael Brinkerink, Christiaan D. Brissenden, Roger Britzen, Silke Broguiere, Dominique Bronzwaer, Thomas Bustamante, Sandra Byun, Do-Young Carlstrom, John E. Ceccobello, Chiara Chan, Chi-Kwan Chang, Dominic O. Chatterjee, Koushik Chatterjee, Shami Chen, Ming-Tang Chen, Yongjun Cheng, Xiaopeng Cho, Ilje Christian, Pierre Conroy, Nicholas S. Conway, John E. Cordes, James M. Crawford, Thomas M. Crew, Geoffrey B. Cruz-Osorio, Alejandro Cui, Yuzhu Dahale, Rohan Davelaar, Jordy De Laurentis, Mariafelicia Deane, Roger Dempsey, Jessica Desvignes, Gregory Dexter, Jason Dhruv, Vedant Doeleman, Sheperd S. Dougal, Sean Dzib, Sergio A. Eatough, Ralph P. Emami, Razieh Falcke, Heino Farah, Joseph Fish, Vincent L. Fomalont, Ed Ford, H. Alyson Foschi, Marianna Fraga-Encinas, Raquel Freeman, William T. Friberg, Per Fromm, Christian M. Fuentes, Antonio Galison, Peter Gammie, Charles F. García, Roberto Gentaz, Olivier Georgiev, Boris Goddi, Ciriaco Gold, Roman Gómez-Ruiz, Arturo I. Gómez, José L. Gu, Minfeng Gurwell, Mark Hada, Kazuhiro Haggard, Daryl Haworth, Kari Hecht, Michael H. Hesper, Ronald Heumann, Dirk Ho, Luis C. Ho, Paul Honma, Mareki Huang, Chih-Wei L. Huang, Lei Hughes, David H. Ikeda, Shiro Impellizzeri, C.M. Violette Inoue, Makoto Issaoun, Sara James, David J. Jannuzi, Buell T. Jeter, Britton Jiang, Wu Jiménez-Rosales, Alejandra Jorstad, Svetlana Joshi, Abhishek V. Jung, Taehyun Karami, Mansour Karuppusamy, Ramesh Kawashima, Tomohisa Keating, Garrett K. Kettenis, Mark Kim, Dong-Jin Kim, Jae-Young Kim, Jongsoo Kim, Junhan Kino, Motoki Koay, Jun Yi Kocherlakota, Prashant Kofuji, Yutaro Koch, Center for Astrophysics Harvard & Smithsonian 60 Garden Street CambridgeMA02138 United States Black Hole Initiative Harvard University 20 Garden Street CambridgeMA02138 United States Radboud University P.O. Box 9010 Nijmegen6500 GL Netherlands Black Hole Initiative Harvard University 20 Garden Street CambridgeMA02138 United States Princeton Gravity Initiative Princeton University Jadwin Hall PrincetonNJ08544 United States 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 Massachusetts Institute of Technology Haystack Observatory 99 Millstone Road WestfordMA01886 United States National Astronomical Observatory of Japan 2-21-1 Osawa Mitaka Tokyo181-8588 Japan Instituto de Astrofísica de Andalucía-CSIC Glorieta de la Astronomía s/n GranadaE-18008 Spain Department of Physics Faculty of Science Universiti Malaya Kuala Lumpur50603 Malaysia Department of Physics & Astronomy The University of Texas at San Antonio One UTSA Circle San AntonioTX78249 United States Institute of Astronomy and Astrophysics Academia Sinica 11F of Astronomy-Mathematics Building AS/NTU No. 1 Sec. 4 Roosevelt Rd. Taipei10617 Taiwan Departament d’Astronomia i Astrofísica Universitat de València C. Dr. Moliner 50 València BurjassotE-46100 Spain Observatori Astronòmic Universitat de València C. Catedrático José Beltrán 2 València PaternaE-46980 Spain Department of Space Earth and Environment Chalmers University of Technology Onsala Space Observatory OnsalaSE-43992 Sweden Steward Observatory Department of Astronomy University of Arizona 933 N. Cherry Ave. TucsonAZ85721 United States Yale Center for Astronomy & Astrophysics Yale Universit

The Event Horizon Telescope (EHT) is a millimeter very-long-baseline interferometry (VLBI) array which has imaged the apparent shadows of the supermassive black holes M87∗ and Sagittarius A∗. Polarimetric data from these observations contain a wealth of information on the black hole and accretion flow properties. In this work, we develop polarimetric geometric modeling methods for mm-VLBI data, focusing on approaches that fit data products with differing degrees of invariance to broad classes of calibration errors. We establish a fitting procedure using a polarimetric "m-ring" model to approximate the image structure near a black hole. By fitting this model to synthetic EHT data from general relativistic magnetohydrodynamic (GRMHD) models, we show that the linear and circular polarization structure can be successfully approximated with relatively few model parameters. We then fit this model to EHT observations of M87∗ taken in 2017. In total intensity and linear polarization, the m-ring fits are consistent with previous results from imaging methods. In circular polarization, the m-ring fits indicate the presence of event-horizon-scale circular polarization structure, with a persistent dipolar asymmetry and orientation across several days. The same structure was recovered independently of observing band, used data products, and model assumptions. Despite this broad agreement, imaging methods do not produce similarly consistent results. Our circular polarization results, which imposed additional assumptions on the source structure, should thus be interpreted with some caution. Polarimetric geometric modeling provides a useful and powerful method to constrain the properties of horizon-scale polarized emission, particularly for sparse arrays like the EHT. © 2023, CC BY.

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Investigating the Nature of the Luminous Ambiguous Nuclear Transient ASASSN-17jz

arXiv

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arXiv 2021年

作者： Holoien, Thomas W.-S. Neustadt, Jack M.M. Vallely, Patrick J. Auchettl, Katie Hinkle, Jason T. Romero-Cañizales, Cristina Shappee, Benjamin J. Kochanek, Christopher S. Stanek, K.Z. Chen, Ping Dong, Subo Prieto, Jose L. Thompson, Todd A. Brink, Thomas G. Filippenko, Alexei V. Zheng, Weikang Bersier, David Bose, Subhash Burgasser, Adam J. Channa, Sanyum De Jaeger, Thomas Hestenes, Julia Im, Myungshin Jeffers, Benjamin Jun, Hyunsung D. Lansbury, George Post, Richard S. Ross, Timothy W. Stern, Daniel Tang, Kevin Tucker, Michael A. Valenti, Stefano Yunus, Sameen Zhang, Keto D. The Observatories of the Carnegie Institution for Science 813 Santa Barbara St. PasadenaCA91101 United States Department of Astronomy The Ohio State University 140 West 18th Avenue ColumbusOH43210 United States School of Physics The University of Melbourne ParkvilleVIC3010 Australia Department of Astronomy and Astrophysics University of California Santa CruzCA95064 United States Institute for Astronomy University of Hawai'i 2680 Woodlawn Drive HonoluluHI96822 United States Institute of Astronomy and Astrophysics Academia Sinica 11F of Astronomy-Mathematics Building AS/NTU No. 1 Roosevelt Rd Taipei10617 Taiwan The Ohio State University 191 W. Woodruff Ave. ColumbusOH43210 United States Kavli Institute for Astronomy and Astrophysics Peking University Yi He Yuan Road 5 Hai Dian District Beijing100871 China Núcleo de Astronomía de la Facultad de Ingeniería y Ciencias Universidad Diego Portales Av. Ejército 441 Santiago Chile Millennium Institute of Astrophysics Santiago Chile Department of Astronomy University of California BerkeleyCA94720-3411 United States Miller Institute for Basic Research in Science University of California BerkeleyCA94720 United States Astrophysics Research Institute Liverpool John Moores University 146 Brownlow Hill LiverpoolL3 5RF United Kingdom Center for Astrophysics and Space Sciences University of California San Diego La Jolla CA92093 United States Department of Applied Physics and Applied Mathematics Columbia University New YorkNY10027-6623 United States SNU Astronomy Research Center Astronomy Program Dept. of Physics and Astronomy Seoul National University Seoul08826 Korea Republic of School of Physics Korea Institute for Advanced Study 85 Hoegiro Dongdaemun-gu Seoul02455 Korea Republic of European Southern Observatory Karl-Schwarzschild-Strasse 2 GarchingD-85748 Germany Post Observatory LexingtonMA02421 United States Jet Propulsion Laboratory California Institute of Technology 4800 Oa

We present observations of the extremely luminous but ambiguous nuclear transient (ANT) ASASSN-17jz, spanning roughly 1200 days of the object's evolution. ASASSN-17jz was discovered by the All-Sky Automated Survey for Supernovae (ASAS-SN) in the galaxy SDSS J171955.84+414049.4 on UT 2017 July 27 at a redshift of z = 0:1641. The transient peaked at an absolute B-band magnitude of MB,peak=-22:81, corresponding to a bolometric luminosity of Lbol,peak= 8.3×1044erg s-1, and exhibited late-time ultraviolet emission that was still ongoing in our latest observations. Integrating the full light curve gives a total emitted energy of Etot= (1.36±0.08)×1052erg, with (0.80±0.02)×1052erg of this emitted within 200 days of peak light. This late-time ultraviolet emission is accompanied by increasing X-ray emission that becomes softer as it brightens. ASASSN-17jz exhibited a large number of spectral emission lines most commonly seen in active galactic nuclei (AGNs) with little evidence of evolution. It also showed transient Balmer features which became fainter and broader over time, and are still being detected > 1000 days after peak brightness. We consider various physical scenarios for the origin of the transient, including supernovae (SNe), tidal disruption events (TDEs), AGN outbursts, and ANTs. We find that the most likely explanation is that ASASSN-17jz was an SN IIn occurring in or near the disk of an existing AGN, and that the late-time emission is caused by the AGN transitioning to a more active state. Copyright © 2021, The Authors. All rights reserved.

关键词： Supernovae

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Linear relation on Hilbert space

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AIP Conference Proceedings 2018年第1期2014卷

作者： R. K. Sari S. Hariyanto Farikhin 1Magister Program of Mathematics Department of Mathematics Faculty of Science and Mathematics Diponegoro University Semarang 50276 Indonesia 2Department of Mathematics Faculty of Science and Mathematics Diponegoro University Semarang 50276 Indonesia

Given ℌ be Hilbert space over ℂ. If ℌ is a Hilbert space then ℌ2 is also Hilbert space. A linear relation on ℌ is a subspace of ℌ2. A linear relation can be multivalued part or not multivalued part. This paper proposes to discuss and show terms that a linear relation is a bounded linear operator and its spectrum analysis. We give the result that if ℜ is an injective relation on ℌ and range of ℜ is dense then ℜ* is also injective and (ℜ*)−1 = (ℜ−1)*. Consequently, if a relation ℜ on ℌ is an injective and self-adjoint, then a relation ℜ-1 is also self-adjoint. If a relation ℜ is a symmetric on ℌ then N(z - ℜ*) = R(z - ℜ)⊥∩ D(z - ℜ*) and N(z - ℜ) = R(z - ℜ*)⊥∩ D(z - ℜ). If a relation ℜ is a symmetric and z ∈ ℂ, then ∥za-b∥2 ≥ q2 ∥a∥2. If a relation ℜ is closed, bounded and |z| ≥ ∥b∥, then z ∈ ρ(ℜ). Consequently, if a relation ℜ is closed, bounded and |z| ≤ ∥b∥, then z ∈ σ(ℜ).

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Evaluating Large Language Models for Enhancing Radiology Specialty Examination: A Comparative Study with Human Performance

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Academic radiology 2025年

作者： Hao-Yun Liu Shyh-Jye Chen Weichung Wang Chung-Hsi Lee Hsian-He Hsu Shu-Huei Shen Hong-Jen Chiou Wen-Jeng Lee Department of Medical Imaging National Taiwan University Hospital Hsin-Chu Branch Br. No.25 Lane 442 Sec.1 Jingguo Rd. Hsinchu City 300 Taiwan ROC (H.Y.L.) National Taiwan University College of Medicine No.1 Jen Ai Road Section 1 Taipei 100 Taiwan ROC (H.Y.L.). Department of Medical Imaging National Taiwan University Hospital No. 7 Zhongshan S. Rd. Zhongzheng Dist. Taipei City 100229 Taiwan (S.J.C. W.J.L.). Institute of Applied Mathematical Sciences Department of Mathematics and Data Science Degree Program National Taiwan University No. 1 Sec. 4 Roosevelt Rd. Taipei 106319 Taiwan (W.W.). Graduate Institute of Health and Biotechnology Law Taipei Medical University 250 Wuxing Street Taipei City Taiwan (C.H.L.). Department of Radiology Tri-Service General Hospital National Defense Medical Center No.325 Sec.2 Chenggong Rd. Neihu District Taipei City Taiwan (H.H.H.). Department of Radiology Taipei Veterans General Hospital No.201 Sec. 2 Shipai Rd. Beitou District Taipei City Taiwan (S.H.S. H.J.C.) National Yang Ming Chiao Tung University School of Medicine No. 118 Sec. 1 Zhongxiao West Road Taipei City 100 Taiwan (S.H.S. H.J.C.). Department of Medical Imaging National Taiwan University Hospital No. 7 Zhongshan S. Rd. Zhongzheng Dist. Taipei City 100229 Taiwan (S.J.C. W.J.L.). Electronic address: wenjeng@***.

RATIONALE AND OBJECTIVES:The radiology specialty examination assesses clinical decision-making, image interpretation, and diagnostic reasoning. With the expansion of medical knowledge, traditional test design faces challenges in maintaining accuracy and relevance. Large language models (LLMs) demonstrate potential in medical education. This study evaluates LLM performance in radiology specialty exams, explores their role in assessing question difficulty, and investigates their reasoning processes, aiming to develop a more objective and efficient framework for exam design. MATERIALS AND METHODS:This study compared the performance of LLMs and human examinees in a radiology specialty examination. Three LLMs (GPT-4o, o1-preview, and GPT-3.5-turbo-1106) were evaluated under zero-shot conditions. Exam accuracy, examinee accuracy, discrimination index, and point-biserial correlation were used to assess LLMs' ability to predict question difficulty and reasoning processes. The data provided by the Taiwan Radiological Society ensures comparability between AI and human performance. RESULTS:As for accuracy, GPT-4o (88.0%) and o1-preview (90.9%) outperformed human examinees (76.3%), whereas GPT-3.5-turbo-1106 showed significantly lower accuracy (50.2%). Question difficulty analysis revealed that newer LLMs excel in solving complex questions, while GPT-3.5-turbo-1106 exhibited greater performance variability. Discrimination index and point-biserial Correlation analyses demonstrated that GPT-4o and o1-preview accurately identified key differentiating questions, closely mirroring human reasoning patterns. These findings suggest that advanced LLMs can assess medical examination difficulty, offering potential applications in exam standardization and question evaluation. CONCLUSION:This study evaluated the problem-solving capabilities of GPT-3.5-turbo-1106, GPT-4o, and o1-preview in a radiology specialty examination. LLMs should be utilized as tools for assessing exam question difficu

关键词： Accuracy Evaluation GPT LLMs Radiology specialty examination

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Partial deconfinement at strong coupling on the lattice

arXiv

引用

arXiv 2020年

作者： Watanabe, Hiromasa Bergner, Georg Bodendorfer, Norbert Funai, Shotaro Shiba Hanada, Masanori Rinaldi, Enrico Schäfer, Andreas Vranas, Pavlos Graduate School of Pure and Applied Sciences University of Tsukuba Tsukuba Ibaraki305-8571 Japan University of Jena Institute for Theoretical Physics Max-Wien-Platz 1 JenaD-07743 Germany University of Regensburg Institute of Theoretical Physics Universitätsstrasse 31 D-93053 Germany 1919-1 Tancha Onna-son Kunigami-gun Okinawa904-0495 Japan Department of Mathematics University of Surrey Guildford SurreyGU2 7XH United Kingdom Arithmer Inc. R&D Headquarters Minato Tokyo106-6040 Japan RIKEN iTHEMS Program Wako Saitama351-0198 Japan Nuclear and Chemical Sciences Division Lawrence Livermore National Laboratory LivermoreCA94550 United States Nuclear Science Division Lawrence Berkeley National Laboratory BerkeleyCA94720 United States

We provide evidence for partial deconfinement - the deconfinement of a SU(M) subgroup of the SU(N) gauge group - by using lattice Monte Carlo simulations. We take matrix models as concrete examples. By appropriately fixing the gauge, we observe that the M×M submatrices deconfine. This gives direct evidence for partial deconfinement at strong coupling. We discuss the applications to QCD and holography. Copyright © 2020, The Authors. All rights reserved.

关键词： Monte Carlo methods

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A Gompertz population model with Allee effect and fuzzy initial values

引用

AIP Conference Proceedings 2018年第1期1937卷

作者： Zenia Amarti Nenden Siti Nurkholipah Nursanti Anggriani Asep K. Supriatna 1Master Student of Mathematics Study Program Faculty of Mathematics and Natural Sciences Universitas Padjadjaran INDONESIA 2Department of Mathematics Faculty of Mathematics and Natural Sciences Universitas Padjadjaran INDONESIA

Growth and population dynamics models are important tools used in preparing a good management for society to predict the future of population or species. This has been done by various known methods, one among them is by developing a mathematical model that describes population growth. Models are usually formed into differential equations or systems of differential equations, depending on the complexity of the underlying properties of the population. One example of biological complexity is Allee effect. It is a phenomenon showing a high correlation between very small population size and the mean individual fitness of the population. In this paper the population growth model used is the Gompertz equation model by considering the Allee effect on the population. We explore the properties of the solution to the model numerically using the Runge-Kutta method. Further exploration is done via fuzzy theoretical approach to accommodate uncertainty of the initial values of the model. It is known that an initial value greater than the Allee threshold will cause the solution rises towards carrying capacity asymptotically. However, an initial value smaller than the Allee threshold will cause the solution decreases towards zero asymptotically, which means the population is eventually extinct. Numerical solutions show that modeling uncertain initial value of the critical point A (the Allee threshold) with a crisp initial value could cause the extinction of population of a certain possibilistic degree, depending on the predetermined membership function of the initial value.

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