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arXiv 2024年

作者： Augier, C. Barabash, A.S. Bellini, F. Benato, G. Beretta, M. Bergé, L. Billard, J. Borovlev, Yu A. Cardani, L. Casali, N. Cazes, A. Celi, Emanuela Chapellier, M. Chiesa, D. Dafinei, I. Danevich, F.A. De Jesus, M. Dixon, T. Dumoulin, L. Eitel, K. Ferri, F. Fujikawa, B.K. Gascon, J. Gironi, L. Giuliani, A. Grigorieva, V.D. Gros, M. Helis, D.L. Huang, H.Z. Huang, R. Imbert, L. Juillard, A. Khalife, H. Kleifges, M. Kobychev, V.V. Kolomensky, Yu G. Konovalov, S.I. Kotila, J. Loaiza, P. Ma, L. Makarov, E.P. de Marcillac, P. Mariam, R. Marini, L. Marnieros, S. Navick, X.F. Nones, C. Norman, E.B. Olivieri, E. Ouellet, J.L. Pagnanini, L. Pattavina, L. Paul, B. Pavan, M. Peng, H. Pessina, G. Pirro, S. Poda, D.V. Polischuk, O.G. Pozzi, S. Previtali, E. Redon, Th Rojas, A. Rozov, S. Sanglard, V. Scarpaci, J.A. Schmidt, B. Shen, Y. Shlegel, V.N. Šimkovic, F. Singh, V. Tomei, C. Tretyak, V.I. Umatov, V.I. Vagneron, L. Velázquez, M. Ware, B. Welliver, B. Winslow, L. Xue, M. Yakushev, E. Zarytskyy, M. Zolotarova, A.S. Univ Lyon Université Lyon 1 CNRS IN2P3 IP2I-Lyon VilleurbanneF-69622 France National Research Centre Kurchatov Institute Kurchatov Complex of Theoretical and Experimental Physics Moscow117218 Russia Dipartimento di Fisica Sapienza Università di Roma P.le Aldo Moro 2 RomeI-00185 Italy INFN Sezione di Roma P.le Aldo Moro 2 RomeI-00185 Italy Gran Sasso Science Institute L’AquilaI-67100 Italy AssergiI-67100 Italy Department of Physics University of California BerkeleyCA94720 United States Université Paris-Saclay CNRS IN2P3 IJCLab Orsay91405 France Nikolaev Institute of Inorganic Chemistry Novosibirsk630090 Russia Dipartimento di Fisica Università di Milano-Bicocca MilanoI-20126 Italy INFN Sezione di Milano-Bicocca MilanoI-20126 Italy Institute for Nuclear Research of National Academy of Sciences of Ukraine Kyiv03028 Ukraine INFN Sezione di Roma Tor Vergata Via della Ricerca Scientifica 1 RomeI-00133 Italy Institute for Astroparticle Physics Karlsruhe Institute of Technology Karlsruhe76021 Germany IRFU CEA Université Paris-Saclay Gif-sur-YvetteF-91191 France Nuclear Science Division Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Fudan University Shanghai200433 China Institute for Data Processing and Electronics Karlsruhe Institute of Technology Karlsruhe76021 Germany 409 Atomistilor Street Bucharest-Magurele077125 Romania Finnish Institute for Educational Research University of Jyväskylä P.O. Box 35 JyväskyläFI-40014 Finland Center for Theoretical Physics Sloane Physics Laboratory Yale University New HavenCT06520-8120 United States Massachusetts Institute of Technology CambridgeMA02139 United States Physik Department Technische Universität München GarchingD-85748 Germany Department of Modern Physics University of Science and Technology of China Hefei230027 China Université Grenoble Alpes CNRS Grenoble INP LPSC/LSM-IN2P3 Modane73500 France Laboratory of Nuclear Problems JINR Moscow

The current experiments searching for neutrinoless double-β (0βvβ) decay also collect large statistics of Standard Model allowed two-neutrino double-β (2vββ) decay events. These can be used to search for Beyond Standard Model (BSM) physics via 2vββ decay spectral distortions. 100Mo has a natural advantage due to its relatively short half-life, allowing higher β2vβ decay statistics at equal exposures compared to the other isotopes. We demonstrate the potential of the dual read-out bolometric technique exploiting a 100Mo exposure of 1.47 kg × y, acquired in the CUPID-Mo experiment at the Modane underground laboratory (France). We set limits on 0vββ decays with the emission of one or more Majorons, on 2vββ decay with Lorentz violation, and 2vββ decay with a sterile neutrino emission. In this analysis, we investigate the systematic uncertainty induced by modeling the 2vββ decay spectral shape parameterized through an improved model, an effect never considered before. This work motivates searches for BSM processes in the upcoming CUPID experiment, which will collect the largest amount of 2vββ decay events among the next-generation experiments. © 2024, CC BY.

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NANOGrav 15-year gravitational-wave background methods

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Physical Review D 2024年第10期109卷 103012-103012页

作者： Aaron D. Johnson Patrick M. Meyers Paul T. Baker Neil J. Cornish Jeffrey S. Hazboun Tyson B. Littenberg Joseph D. Romano Stephen R. Taylor Michele Vallisneri Sarah J. Vigeland Ken D. Olum Xavier Siemens Justin A. Ellis Rutger van Haasteren Sophie Hourihane Gabriella Agazie Akash Anumarlapudi Anne M. Archibald Zaven Arzoumanian Laura Blecha Adam Brazier Paul R. Brook Sarah Burke-Spolaor Bence Bécsy J. Andrew Casey-Clyde Maria Charisi Shami Chatterjee Katerina Chatziioannou Tyler Cohen James M. Cordes Fronefield Crawford H. Thankful Cromartie Kathryn Crowter Megan E. DeCesar Paul B. Demorest Timothy Dolch Brendan Drachler Elizabeth C. Ferrara William Fiore Emmanuel Fonseca Gabriel E. Freedman Nate Garver-Daniels Peter A. Gentile Joseph Glaser Deborah C. Good Kayhan Gültekin Ross J. Jennings Megan L. Jones Andrew R. Kaiser David L. Kaplan Luke Zoltan Kelley Matthew Kerr Joey S. Key Nima Laal Michael T. Lam William G. Lamb T. Joseph W. Lazio Natalia Lewandowska Tingting Liu Duncan R. Lorimer Jing Luo Ryan S. Lynch Chung-Pei Ma Dustin R. Madison Alexander McEwen James W. McKee Maura A. McLaughlin Natasha McMann Bradley W. Meyers Chiara M. F. Mingarelli Andrea Mitridate Cherry Ng David J. Nice Stella Koch Ocker Timothy T. Pennucci Benetge B. P. Perera Nihan S. Pol Henri A. Radovan Scott M. Ransom Paul S. Ray Shashwat C. Sardesai Carl Schmiedekamp Ann Schmiedekamp Kai Schmitz Brent J. Shapiro-Albert Joseph Simon Magdalena S. Siwek Ingrid H. Stairs Daniel R. Stinebring Kevin Stovall Abhimanyu Susobhanan Joseph K. Swiggum Jacob E. Turner Caner Unal Haley M. Wahl Caitlin A. Witt Olivia Young Center for Gravitation Cosmology and Astrophysics Department of Physics University of Wisconsin-Milwaukee P.O. Box 413 Milwaukee Wisconsin 53201 USA Division of Physics Mathematics and Astronomy California Institute of Technology Pasadena California 91125 USA Department of Physics and Astronomy Widener University One University Place Chester Pennsylvania 19013 USA Department of Physics Montana State University Bozeman Montana 59717 USA Department of Physics Oregon State University Corvallis Oregon 97331 USA NASA Marshall Space Flight Center Huntsville Alabama 35812 USA Department of Physics Texas Tech University Box 41051 Lubbock Texas 79409 USA Department of Physics and Astronomy Vanderbilt University 2301 Vanderbilt Place Nashville Tennessee 37235 USA Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Drive Pasadena California 91109 USA Institute of Cosmology Department of Physics and Astronomy Tufts University Medford Massachusetts 02155 USA Department of Astronomy University of Maryland College Park Maryland 20742 Center for Research and Exploration in Space Science and Technology NASA/GSFC Greenbelt Maryland 20771 NASA Goddard Space Flight Center Greenbelt Maryland 20771 USA Max-Planck-Institut für Gravitationsphysik (Albert-Einstein-Institut) Callinstrasse 38 D-30167 Hannover Germany Newcastle University NE1 7RU Newcastle United Kingdom X-Ray Astrophysics Laboratory NASA Goddard Space Flight Center Code 662 Greenbelt Maryland 20771 USA Physics Department University of Florida Gainesville Florida 32611 USA Cornell Center for Astrophysics and Planetary Science and Department of Astronomy Cornell University Ithaca New York 14853 USA Cornell Center for Advanced Computing Cornell University Ithaca New York 14853 USA Institute for Gravitational Wave Astronomy and School of Physics and Astronomy University of Birmingham Edgbaston Birmingham B15 2TT United Kingdom Department of Physics and Astronomy West

Pulsar timing arrays (PTAs) use an array of millisecond pulsars to search for gravitational waves in the nanohertz regime in pulse time of arrival data. This paper presents rigorous tests of PTA methods, examining their consistency across the relevant parameter space. We discuss updates to the 15-year isotropic gravitational-wave background analyses and their corresponding code representations. Descriptions of the internal structure of the flagship algorithms enterprise and ptmcmcsampler are given to facilitate understanding of the PTA likelihood structure, how models are built, and what methods are currently used in sampling the high-dimensional PTA parameter space. We introduce a novel version of the PTA likelihood that uses a two-step marginalization procedure that performs much faster in gravitational wave searches, reducing the required resources facilitating the computation of Bayes factors via thermodynamic integration and sampling a large number of realizations for computing Bayesian false-alarm probabilities. We perform stringent tests of consistency and correctness of the Bayesian and frequentist analysis methods. For the Bayesian analysis, we test prior recovery, simulation recovery, and Bayes factors. For the frequentist analysis, we test that the optimal statistic, when modified to account for a non-negligible gravitational-wave background, accurately recovers the amplitude of the background. We also summarize recent advances and tests performed on the optimal statistic in the literature from both gravitational wave background detection and parameter estimation perspectives. The tests presented here validate current analyses of PTA data.

关键词： Gravitational waves Gravitational wave detection

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Trapping of null geodesics in slowly rotating spacetimes

arXiv

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arXiv 2020年

作者： Vrba, Jaroslav Urbanec, Martin Stuchlík, Zdeněk Miller, John C. Research Centre for Theoretical Physics and Astrophysics Institute of Physics in Opava Silesian University in Opava Bezručovo náměstí 13 OpavaCZ-74601 Czech Republic Research Centre for Computational Physics and Data Processing Institute of Physics in Opava Silesian University in Opava Bezručovo náměstí 13 OpavaCZ-74601 Czech Republic University of Oxford Keble Road OxfordOX1 3RH United Kingdom

Extremely compact objects containing a region of trapped null geodesics could be of astrophysical relevance due to trapping of neutrinos with consequent impact on cooling processes or trapping of gravitational waves. These objects have previously been studied under the assumption of spherical symmetry. In the present paper, we consider a simple generalization by studying trapping of null geodesics in the framework of the Hartle-Thorne slow-rotation approximation taken to first order in the angular velocity, and considering a uniform-density object with uniform emissivity for the null geodesics. We calculate effective potentials and escape cones for the null geodesics and how they depend on the parameters of the spacetimes, and also calculate the "local" and "global" coefficients of efficiency for the trapping. We demonstrate that due to the rotation the trapping efficiency is different for co-rotating and retrograde null geodesics, and that trapping can occur even for R > 3GM/c2, contrary to what happens in the absence of rotation. Copyright © 2020, The Authors. All rights reserved.

关键词： Efficiency

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Machine Learning for Mini-EUSO Telescope data Analysis 38

Machine Learning for Mini-EUSO Telescope Data Analysis

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38th International Cosmic Ray Conference, ICRC 2023

作者： Bertaina, Mario Zotov, Mikhail Anzhiganov, Dmitry Barghini, Dario Blaksley, Carl Coretti, Antonio Giulio Kryazhenkov, Aleksandr Montanaro, Antonio Olivi, Leonardo Abe, S. Adams, J.H. Allard, D. Alldredge, P. Aloisio, R. Anchordoqui, L. Anzalone, A. Arnone, E. Bagheri, M. Baret, B. Barghini, D. Battisti, M. Bellotti, R. Belov, A.A. Bertaina, M. Bertone, P.F. Bianciotto, M. Bisconti, F. Blaksley, C. Blin-Bondil, S. Bolmgren, K. Briz, S. Burton, J. Cafagna, F. Cambié, G. Campana, D. Capel, F. Caruso, R. Casolino, M. Cassardo, C. Castellina, A. Černý, K. Christl, M.J. Colalillo, R. Conti, L. Cotto, G. Crawford, H.J. Cremonini, R. Creusot, A. Cummings, A. de Castro Gónzalez, A. de la Taille, C. Diesing, R. Dinaucourt, P. Di Nola, A. Ebisuzaki, T. Eser, J. Fenu, F. Ferrarese, S. Filippatos, G. Finch, W.W. Flaminio, F. Fornaro, C. Fuehne, D. Fuglesang, C. Fukushima, M. Gadamsetty, S. Gardiol, D. Garipov, G.K. Gazda, E. Golzio, A. Guarino, F. Guépin, C. Haungs, A. Heibges, T. Isgrò, F. Judd, E.G. Kajino, F. Kaneko, I. Kim, S.-W. Klimov, P.A. Krizmanic, J.F. Kungel, V. Kuznetsov, E. López Martínez, F. Mandát, D. Manfrin, M. Marcelli, A. Marcelli, L. Marszal, W. Matthews, J.N. Mese, M. Meyer, S.S. Mimouni, J. Miyamoto, H. Mizumoto, Y. Monaco, A. Nagataki, S. Nachtman, J.M. Naumov, D. Neronov, A. Nonaka, T. Ogawa, T. Ogio, S. Ohmori, H. Olinto, A.V. Onel, Y. Osteria, G. Otte, A.N. Pagliaro, A. Panico, B. Parizot, E. Park, I.H. Paul, T. Pech, M. Perfetto, F. Picozza, P. Piotrowski, L.W. Plebaniak, Z. Posligua, J. Potts, M. Prevete, R. Prévôt, G. Przybylak, M. Reali, E. Reardon, P. Reno, M.H. Ricci, M. Romero Matamala, O.F. Romoli, G. Sagawa, H. Sakaki, N. Saprykin, O.A. Sarazin, F. Sato, M. Schovánek, P. Scotti, V. Selmane, S. Sharakin, S.A. Shinozaki, K. Stepanoff, S. Soriano, J.F. Szabelski, J. Tajima, N. Tajima, T. Takahashi, Y. Takeda, M. Takizawa, Y. Thomas, S.B. Tkachev, L.G. Tomida, T. Toscano, S. Dipartimento di Fisica Università di Torino Torino Italy INFN Sezione di Torino Torino Italy Skobeltsyn Institute of Nuclear Physics Lomonosov Moscow State University Moscow Russia Faculty of Computational Mathematics and Cybernetics Lomonosov Moscow State University Moscow Russia INAF Osservatorio astrofisico di Torino Torino Italy Department of Electronics and Telecommunications Polytechnic University of Turin Corso Duca degli Abruzzi 24 Turin10129 Italy Algiers Algeria Univ. Constantine I Constantine Algeria Joint Laboratory of Optics Faculty of Science Palacký University Olomouc Czech Republic Institute of Physics The Czech Academy of Sciences Prague Czech Republic Omega Ecole Polytechnique CNRS IN2P3 Palaiseau France Université de Paris CNRS AstroParticule et Cosmologie ParisF-75013 France France Germany Max Planck Institute for Physics Munich Germany Istituto Nazionale di Fisica Nucleare - Sezione di Bari Italy Università degli Studi di Bari Aldo Moro Italy Dipartimento di Fisica e Astronomia "Ettore Majorana" Università di Catania Italy Istituto Nazionale di Fisica Nucleare - Sezione di Catania Italy Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali di Frascati Italy Istituto Nazionale di Fisica Nucleare - Sezione di Napoli Italy Università di Napoli Federico II Dipartimento di Fisica "Ettore Pancini" Italy INAF - Istituto di Astrofisica Spaziale e Fisica Cosmica di Palermo Italy Istituto Nazionale di Fisica Nucleare - Sezione di Roma Tor Vergata Italy Università di Roma Tor Vergata - Dipartimento di Fisica Roma Italy Istituto Nazionale di Fisica Nucleare - Sezione di Torino Italy Dipartimento di Fisica Università di Torino Italy Osservatorio Astrofisico di Torino Istituto Nazionale di Astrofisica Italy Uninettuno University Rome Italy Agenzia Spaziale Italiana Via del Politecnico Roma00133 Italy Gran Sasso Science Institute L’Aquila Italy Institute for Cosmic Ray Research University of Tokyo Kashiwa Japan Konan Universi

Neural networks as well as other methods of machine learning (ML) are known to be highly efficient in different classification tasks, including classification of images and videos. Mini-EUSO is a wide-field-of-view imaging telescope that operates onboard the International Space Station since 2019 collecting data on miscellaneous processes that take place in the atmosphere of Earth in the UV range. Here we briefly present our results on the development of ML-based approaches for recognition and classification of track-like signals in the Mini-EUSO data, among them meteors, space debris and signals the light curves and kinematics of which are similar to those expected from extensive air showers generated by ultra-high-energy cosmic rays. We show that even simple neural networks demonstrate impressive performance in solving these tasks. © Copyright owned by the author(s) under the terms of the Creative Commons.

关键词： Cosmology

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Probing Globular Cluster with MeerKAT and FAST: A Pulsar Polarization Census

arXiv

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arXiv 2025年

作者： Zhang, Lei Abbate, Federico Li, Di Possenti, Andrea Bailes, Matthew Ridolfi, Alessandro Freire, Paulo C.C. Ransom, Scott M. Zhang, Yong-Kun Guo, Meng Ni, Meng-Meng Hu, Jia-Le Feng, Yi Wang, Pei Zhang, Jie Zhi, Qi-Jun National Astronomical Observatories Chinese Academy of Sciences Beijing100101 China Centre for Astrophysics and Supercomputing Swinburne University of Technology VIC3122 Australia INAF Osservatorio Astronomico di Cagliari Via della Scienza 5 SelargiusI-09047 Italy Max-Planck-Institut für Radioastronomie Auf dem Hügel 69 BonnD-53121 Germany Department of Astronomy Tsinghua University Beijing100190 China Swinburne University of Technology VIC3122 Australia Faculty of Physics University of Bielefeld Bielefeld33501 Germany National Radio Astronomy Observatory 520 Edgemont Road Charlottesville22903 United States National Supercomputing Center in Jinan Qilu University of Technology Jinan250103 China Jinan Institute of Supercomputing Technology 28666 East Jingshi Road Jinan250103 China Research Center for Intelligent Computing Platforms Zhejiang Laboratory Hangzhou311100 China Institute for Astronomy School of Physics Zhejiang University Hangzhou310027 China College of Physics and Electronic Engineering Qilu Normal University Jinan250200 China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal University Guiyang550001 China

Only one globular cluster (GC), 47 Tuc, has been found to containintracluster medium, with an electron density 100 times higher than that of theISM in its vicinity. The characteristics of this intracluster medium areclosely related to GC evolution and the compact objects within. However,significant knowledge gaps remain regarding the ionized gas content of GCs,particularly in Galactic halo clusters. We carried out a polarization census ofGC pulsars using MeerKAT and FAST. This first combined effort of observationsfrom these two major radio telescopes resulted in high signal-to-noise ratio,full polarization pulse profiles for 43 pulsars in 8 GCs, doubling the numberof rotation measures (RMs) known in these clusters. The accuracy of dispersionmeasures (DMs) was improved by a factor of 8 compared to previous *** intracluster medium was found, and at least two halo GCs showed morestringent upper limits on electron density than that detected in 47 Tuc. Thesurprising barrenness of GCs suggests effective gas removal mechanisms, such asstrong winds from millisecond pulsars and/or ionizing radiation from post-AGBstars and young white dwarfs. Copyright © 2025, The Authors. All rights reserved.

关键词： White dwarfs

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A robust collision source method for rank adaptive dynamical low-rank approximation in radiation therapy

arXiv

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arXiv 2021年

作者： Kusch, Jonas Stammer, Pia Karlsruhe Institute of Technology Mathematical Science and Computational Methods Karlsruhe Germany Karlsruhe Institute of Technology Steinbuch Centre for Computing Karlsruhe Germany German Cancer Research Center - DKFZ Department of Medical Physics in Radiation Oncology Heidelberg Germany HIDSS4Health - Helmholtz Information and Data Science School for Health Karlsruhe/Heidelberg Germany

Deterministic models for radiation transport describe the density of radiation particles moving through a background material. In radiation therapy applications, the phase space of this density is composed of energy, spatial position and direction of flight. The resulting six-dimensional phase space prohibits fine numerical discretizations, which are essential for the construction of accurate and reliable treatment plans. In this work, we tackle the high dimensional phase space through a dynamical low-rank approximation of the particle density. Dynamical low-rank approximation (DLRA) evolves the solution on a low-rank manifold in time. Interpreting the energy variable as a pseudo-time lets us employ the DLRA framework to represent the solution of the radiation transport equation on a low-rank manifold for every energy. Stiff scattering terms are treated through an efficient implicit energy discretization and a rank adaptive integrator is chosen to dynamically adapt the rank in energy. To facilitate the use of boundary conditions and reduce the overall rank, the radiation transport equation is split into collided and uncollided particles through a collision source method. Uncollided particles are described by a directed quadrature set guaranteeing low computational costs, whereas collided particles are represented by a low-rank solution. It can be shown that the presented method is L2-stable under a time step restriction which does not depend on stiff scattering terms. Moreover, the implicit treatment of scattering does not require numerical inversions of matrices. Numerical results for radiation therapy configurations as well as the line source benchmark underline the efficiency of the proposed method. Copyright © 2021, The Authors. All rights reserved.

关键词： Phase space methods

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RUBIES: JWST/NIRSpec Confirmation of an Infrared-luminous, Broad-line Little Red Dot with an Ionized Outflow

arXiv

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arXiv 2024年

作者： Wang, Bingjie de Graaff, Anna Davies, Rebecca L. Greene, Jenny E. Leja, Joel Brammer, Gabriel B. Goulding, Andy D. Miller, Tim B. Suess, Katherine A. Weibel, Andrea Williams, Christina C. Bezanson, Rachel Boogaard, Leindert A. Cleri, Nikko J. Hirschmann, Michaela Katz, Harley Labbé, Ivo Maseda, Michael V. Matthee, Jorryt McConachie, Ian Naidu, Rohan P. Oesch, Pascal A. Rix, Hans-Walter Setton, David J. Whitaker, Katherine E. Department of Astronomy & Astrophysics The Pennsylvania State University University ParkPA16802 United States Institute for Computational & Data Sciences The Pennsylvania State University University ParkPA16802 United States Institute for Gravitation and the Cosmos The Pennsylvania State University University ParkPA16802 United States Max-Planck-Institut für Astronomie Königstuhl 17 HeidelbergD-69117 Germany Centre for Astrophysics and Supercomputing Swinburne University of Technology HawthornVIC3122 Australia Australia Department of Astrophysical Sciences Princeton University PrincetonNJ08544 United States Copenhagen Denmark Niels Bohr Institute University of Copenhagen Jagtvej 128 Copenhagen Denmark Department of Physics & Astronomy Northwestern University IL60201 United States Kavli Institute for Particle Astrophysics and Cosmology Department of Physics Stanford University StanfordCA94305 United States Department of Astronomy University of Geneva Chemin Pegasi 51 Versoix1290 Switzerland NSF’s National Optical-Infrared Astronomy Research Laboratory TucsonAZ85719 United States Steward Observatory University of Arizona TucsonAZ85721 United States Department of Physics & Astronomy and PITT PACC University of Pittsburgh PittsburghPA15260 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 StationTX77843-4242 United States Institute of Physics Lab for galaxy evolution EPFL Observatoire de Sauverny Chemin Pegasi 51 Versoix1290 Switzerland Sub-department of Astrophysics University of Oxford OxfordOX1 3RH United Kingdom Centre for Astrophysics and Supercomputing Swinburne University of Technology MelbourneVIC3122 Australia Department of Astronomy University of Wisconsin-Madison MadisonWI53706 United States Am Campus 1 Klosterneuburg3400 Austria

The JWST discovery of "little red dots" (LRDs) is reshaping our picture of the early Universe, yet the physical mechanisms driving their compact size and UV-optical colors remain elusive. Here we report an unusually bright LRD (zspec = 3.1) observed as part of the RUBIES program. This LRD exhibits broad emission lines (FWHM∼ 4000 km s−1), a blue UV continuum, a clear Balmer break and a red continuum sampled out to rest-frame 4 µm with MIRI. We develop a new joint galaxy and active galactic nucleus (AGN) model within the Prospector Bayesian inference framework and perform spectrophotometric modeling using NIRCam, MIRI, and NIRSpec/Prism observations. Our fiducial model reveals a M∗ ∼ 109 M☉ galaxy alongside a dust-reddened AGN driving the optical emission. Explaining the rest-frame optical color as a reddened AGN requires AV 3, suggesting that a great majority of the accretion disk energy is re-radiated as dust emission. Yet, despite clear AGN signatures, we find a surprising lack of hot torus emission, which implies that either the dust emission in this object must be cold, or the red continuum must instead be driven by a massive, evolved stellar population of the host galaxy—seemingly inconsistent with the high EW broad lines (Hα rest-frame EW ∼ 800 Å). The widths and luminosities of Pa-β, Pa-δ, Pa-γ, and Hα imply a modest black hole mass of MBH ∼ 108 M☉. Additionally, we identify a narrow blue-shifted He i λ1.083 µm absorption feature in NIRSpec/G395M spectra, signaling an ionized outflow with kinetic energy up to ∼ 1% the luminosity of the AGN. The low redshift of RUBIES-BLAGN-1 combined with the depth and richness of the JWST imaging and spectroscopic observations provide a unique opportunity to build a physical model for these so-far mysterious LRDs, which may prove to be a crucial phase in the early formation of massive galaxies and their supermassive black holes. Copyright © 2024, The Authors. All rights reserved.

关键词： Active Galactic Nuclei

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RUBIES: Evolved Stellar Populations with Extended Formation Histories at z ∼ 7 − 8 in Candidate Massive Galaxies Identified with JWST/NIRSpec

arXiv

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arXiv 2024年

作者： Wang, Bingjie Leja, Joel de Graaff, Anna Brammer, Gabriel B. Weibel, Andrea van Dokkum, Pieter Baggen, Josephine F.W. Suess, Katherine A. Greene, Jenny E. Bezanson, Rachel Cleri, Nikko J. Hirschmann, Michaela Labbé, Ivo Matthee, Jorryt McConachie, Ian Naidu, Rohan P. Nelson, Erica Oesch, Pascal A. Setton, David J. Williams, Christina C. Department of Astronomy & Astrophysics The Pennsylvania State University University ParkPA16802 United States Institute for Computational & Data Sciences The Pennsylvania State University University ParkPA16802 United States Institute for Gravitation and the Cosmos The Pennsylvania State University University ParkPA16802 United States Max-Planck-Institut für Astronomie Königstuhl 17 HeidelbergD-69117 Germany Copenhagen Denmark Niels Bohr Institute University of Copenhagen Jagtvej 128 Copenhagen Denmark Department of Astronomy University of Geneva Chemin Pegasi 51 Versoix1290 Switzerland Department of Astronomy Yale University New HavenCT06511 United States Kavli Institute for Particle Astrophysics and Cosmology Department of Physics Stanford University StanfordCA94305 United States Department of Astrophysical Sciences Princeton University PrincetonNJ08544 United States Department of Physics & Astronomy PITT PACC University of Pittsburgh PittsburghPA15260 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 StationTX77843-4242 United States Institute of Physics Lab for Galaxy Evolution EPFL Observatoire de Sauverny Chemin Pegasi 51 Versoix1290 Switzerland Centre for Astrophysics and Supercomputing Swinburne University of Technology MelbourneVIC3122 Australia Am Campus 1 Klosterneuburg3400 Austria Department of Physics and Astronomy University of California Riverside RiversideCA92521 United States MIT Kavli Institute for Astrophysics and Space Research CambridgeMA02139 United States Department for Astrophysical and Planetary Science University of Colorado BoulderCO80309 United States NSF's National Optical-Infrared Astronomy Research Laboratory TucsonAZ85719 United States Steward Observatory University of Arizona TucsonAZ85721 United States

The identification of red, apparently massive galaxies at z > 7 in early James Webb Space Telescope (JWST) photometry suggests a strongly accelerated timeline compared to standard models of galaxy growth. A major uncertainty in the interpretation is whether the red colors are caused by evolved stellar populations, dust, or other effects such as emission lines or AGN. Here we show that three of the massive galaxy candidates at z = 6.7 − 8.4 have prominent Balmer breaks in JWST/NIRSpec spectroscopy from the RUBIES program. The Balmer breaks demonstrate unambiguously that stellar emission dominates at λrest = 0.4 µm, and require formation histories extending hundreds of Myr into the past in galaxies only 600-800 Myr after the Big Bang. Two of the three galaxies also show broad Balmer lines, with Hβ FWHM > 2500 km s−1, suggesting that dust-reddened AGN contribute to, or even dominate, the SEDs of these galaxies at λrest 0.6 µm. All three galaxies have relatively narrow [O iii] lines, seemingly ruling out a high-mass interpretation if the lines arise in dynamically-relaxed, inclined disks. Yet, the inferred masses also remain highly uncertain. We model the high-quality spectra using Prospector to decompose the continuum into stellar and AGN components, and explore limiting cases in stellar/AGN contribution. This produces a wide range of possible stellar masses, spanning M* ∼ 109 − 1011 M☉. Nevertheless, all fits suggest a very early and rapid formation, most of which follow with a truncation in star formation. Potential origins and evolutionary tracks for these objects are discussed, from the cores of massive galaxies to low-mass galaxies with over-massive black holes. Intriguingly, we find all of these explanations to be incomplete;deeper and redder data are needed to understand the physics of these systems. Copyright © 2024, The Authors. All rights reserved.

关键词： Stars

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New measurement of double-β decays of Mo100 to excited states of Ru100 with the CUPID-Mo experiment

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Physical Review C 2023年第2期107卷 025503-025503页

作者： C. Augier A. S. Barabash F. Bellini G. Benato M. Beretta L. Bergé J. Billard Yu. A. Borovlev L. Cardani N. Casali A. Cazes M. Chapellier D. Chiesa I. Dafinei F. A. Danevich M. De Jesus T. Dixon L. Dumoulin K. Eitel F. Ferri B. K. Fujikawa J. Gascon L. Gironi A. Giuliani V. D. Grigorieva M. Gros D. L. Helis H. Z. Huang R. Huang L. Imbert J. Johnston A. Juillard H. Khalife M. Kleifges V. V. Kobychev Yu. G. Kolomensky S. I. Konovalov J. Kotila P. Loaiza L. Ma E. P. Makarov P. de Marcillac R. Mariam L. Marini S. Marnieros X.-F. Navick C. Nones E. B. Norman E. Olivieri J. L. Ouellet L. Pagnanini L. Pattavina B. Paul M. Pavan H. Peng G. Pessina S. Pirro D. V. Poda O. G. Polischuk S. Pozzi E. Previtali Th. Redon A. Rojas S. Rozov V. Sanglard J. A. Scarpaci B. Schmidt Y. Shen V. N. Shlegel V. Singh C. Tomei V. I. Tretyak V. I. Umatov L. Vagneron M. Velázquez B. Welliver L. Winslow M. Xue E. Yakushev M. Zarytskyy A. S. Zolotarova Univ. Lyon Université Lyon 1 CNRS/IN2P3 IP2I-Lyon F-69622 Villeurbanne France National Research Centre Kurchatov Institute Institute of Theoretical and Experimental Physics 117218 Moscow Russia Dipartimento di Fisica Sapienza Università di Roma P.le Aldo Moro 2 I-00185 Rome Italy INFN Sezione di Roma P.le Aldo Moro 2 I-00185 Rome Italy INFN Laboratori Nazionali del Gran Sasso I-67100 Assergi (AQ) Italy University of California Berkeley California 94720 USA Université Paris-Saclay CNRS/IN2P3 IJCLab 91405 Orsay France Nikolaev Institute of Inorganic Chemistry 630090 Novosibirsk Russia Dipartimento di Fisica Università di Milano-Bicocca I-20126 Milano Italy INFN Sezione di Milano-Bicocca I-20126 Milano Italy Institute for Nuclear Research of NASU 03028 Kyiv Ukraine IRFU CEA Université Paris-Saclay F-91191 Gif-sur-Yvette France Karlsruhe Institute of Technology Institute for Astroparticle Physics 76021 Karlsruhe Germany Lawrence Berkeley National Laboratory Berkeley California 94720 USA Key Laboratory of Nuclear Physics and Ion-beam Application (MOE) Fudan University Shanghai 200433 P.R. China Massachusetts Institute of Technology Cambridge Massachusetts 02139 USA Karlsruhe Institute of Technology Institute for Data Processing and Electronics 76021 Karlsruhe Germany Department of Physics University of Jyväskylä P.O. Box 35 FI-40014 Jyväskylä Finland Finnish Institute for Educational Research University of Jyväskylä P.O. Box 35 FI-40014. Jyväskylä Finland Center for Theoretical Physics Sloane Physics Laboratory Yale University New Haven Connecticut 06520-8120 USA INFN Gran Sasso Science Institute I-67100 L'Aquila Italy Physik Department Technische Universität München Garching D-85748 Germany Department of Modern Physics University of Science and Technology of China Hefei 230027 P.R. China LSM Laboratoire Souterrain de Modane 73500 Modane France Laboratory of Nuclear Problems JINR 141980 Dubna Moscow region Russia Université Grenobl

The CUPID-Mo experiment, located at the Laboratoire Souterrain de Modane (France), was a demonstrator experiment for CUPID. It consisted of an array of 20Li2Mo100O4 (LMO) calorimeters, each equipped with a Ge light detector for particle identification. In this work, we present the result of a search for two-neutrino and neutrinoless double-β decays of Mo100 to the first 0+ and 2+ excited states of Ru100 using the full CUPID-Mo exposure (2.71kgyr of LMO). We measure the half-life of 2νββ decay to the 01+ state as T1/22ν→01+=(7.5±0.8(stat.)−0.3+0.4(syst.))×1020yr. The bolometric technique enables measurement of the electron energies as well as the γ rays from nuclear deexcitation and this allows us to set new limits on the two-neutrino decay to the 21+ state of T1/22ν→21+>4.4×1021yr(90% c.i.) and on the neutrinoless modes of T1/20ν→21+>2.1×1023yr(90% c.i.), T1/20ν→01+>1.2×1023yr(90% c.i.). Information on the electrons' spectral shape is obtained, which allows us to make the first comparison of the single and higher state dominance 2νββ decay models for the 01+ excited state of Ru100.

关键词： Double beta decay Neutrinoless double beta decay Nuclear structure & decays Majorana neutrinos Neutrinos 90 ≤ A ≤ 149

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Prediction of Activated Sludge Settling Characteristics from Microscopy Images with Deep Convolutional Neural Networks and Transfer Learning

SSRN

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SSRN 2024年

作者： Borzooei, Sina Scabini, Leonardo F.S. Miranda, Gisele Daneshgar, Saba Deblieck, Lukas De Langhe, Piet Bruno, Odemir De Baets, Bernard Nopens, Ingmar Torfs, Elena IVL Swedish Environmental Research Institute PO Box 210 60 StockholmSE-100 31 Sweden Department of Data Analysis and Mathematical Modelling Faculty of Bioscience Engineering Ghent University Coupure links 653 Gent9000 Belgium São Carlos Institute of Physics University of São Paulo SP São Carlos13560-970 Brazil KERMIT Department of Data Analysis and Mathematical Modelling Ghent University Coupure links 653 Gent9000 Belgium Division of Computational Science and Technology KTH Royal Institute of Technology Stockholm10044 Sweden CAPTURE Centre for Advanced Process Technology for Urban Resource Recovery Frieda Saeysstraat 1 Gent9000 Belgium Pantarein Water Egide Walschaertsstraat 22L Mechelen2800 Belgium Université Laval 1065 avenue de la Médecine QuébecQCG1V 0A6 Canada

Timely assessment and prediction of changes in microbial compositions leading to activated sludge settling problems, such as filamentous bulking (FB), can reduce water resource recovery facilities (WRRFs) upsets, operational challenges, and negative environmental impacts. This study presents a computer vision approach to assess activated sludge-settling characteristics based on Microscopy Images (MIs). We utilize MIs to train deep convolutional neural networks (CNN) using transfer learning to investigate the morphological properties of flocs and filaments. The methodology was tested on the offline MI dataset collected over two years at a full-scale industrial WRRF in Belgium. Various CNN architectures were tested, including Inception v3, ResNet18, ResNet152, ConvNeXt-nano, and ConvNeXt-S. The sludge volume index (SVI) was used as the final prediction variable, but the method can be easily adjusted to predict any other settling metric of choice. The best-performing CNN, ConvNeXt-nano, could predict SVI values with MAE (37.51 ± 4.02), MTD (11.65 ± 1.94), MAPE (0.18 ± 0.02), and R2 (0.75 ± 0.05). The model was tested in real-life FB events, where it identified early indicators of bulking by predictive surges in SVI values. We also use an explainable AI technique, Eigen-CAM, to discover key morphological indicators of sludge bulking transitions. The findings highlight the SVI multimodality issue, where SVI readings as a unidimensional metric could not capture delicate shifts from good to poor sludge settling, while the model detected these subtle changes. The key morphological attributes of threshold conditions leading to FB were identified, which can provide actionable insight for preemptive WRRF management. © 2024, The Authors. All rights reserved.

关键词： Forecasting

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