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Deep Generative Models for Fast Photon Shower Simulation in ATLAS

Computing and Software for Big science 2024年第1期8卷 1-40页

作者： Aad, G. Abbott, B. Abbott, D.C. Abud, A. Abed Abeling, K. Abhayasinghe, D.K. Abidi, S.H. Aboulhorma, A. Abramowicz, H. Abreu, H. Abulaiti, Y. Hoffman, A. C. Abusleme Acharya, B.S. Achkar, B. Adam, L. Bourdarios, C. Adam Adamczyk, L. Adamek, L. Addepalli, S.V. Adelman, J. Adiguzel, A. Adorni, S. Adye, T. Affolder, A.A. Afik, Y. Agaras, M.N. Agarwala, J. Aggarwal, A. Agheorghiesei, C. Aguilar-Saavedra, J.A. Ahmad, A. Ahmadov, F. Ahmed, W.S. Ai, X. Aielli, G. Aizenberg, I. Akbiyik, M. Åkesson, T.P.A. Akimov, A.V. Khoury, K. Al Alberghi, G.L. Albert, J. Albicocco, P. Verzini, M. J. Alconada Alderweireldt, S. Aleksa, M. Aleksandrov, I.N. Alexa, C. Alexopoulos, T. Alfonsi, A. Alfonsi, F. Alhroob, M. Ali, B. Ali, S. Aliev, M. Alimonti, G. Allaire, C. Allbrooke, B.M.M. Allport, P.P. Aloisio, A. Alonso, F. Alpigiani, C. Camelia, E. Alunno Estevez, M. Alvarez Alviggi, M.G. Coutinho, Y. Amaral Ambler, A. Ambroz, L. Amelung, C. Amidei, D. Santos, S. P. Amor Dos Amoroso, S. Amos, K.R. Amrouche, C.S. Ananiev, V. Anastopoulos, C. Andari, N. Andeen, T. Anders, J.K. Andrean, S.Y. Andreazza, A. Angelidakis, S. Angerami, A. Anisenkov, A.V. Annovi, A. Antel, C. Anthony, M.T. Antipov, E. Antonelli, M. Antrim, D.J.A. Anulli, F. Aoki, M. Pozo, J. A. Aparisi Aparo, M.A. Bella, L. Aperio Appelt, C. Aranzabal, N. Ferraz, V. Araujo Arcangeletti, C. Arce, A.T.H. Arena, E. Arguin, J.-F. Argyropoulos, S. Arling, J.-H. Armbruster, A.J. Arnaez, O. Arnold, H. Tame, Z. P. Arrubarrena Artoni, G. Asada, H. Asai, K. Asai, S. Asbah, N.A. Asimakopoulou, E.M. Assahsah, J. Assamagan, K. Astalos, R. Atkin, R.J. Atkinson, M. Atlay, N.B. Atmani, H. Atmasiddha, P.A. Augsten, K. Auricchio, S. Austrup, V.A. Avner, G. Avolio, G. Ayoub, M.K. Azuelos, G. Babal, D. Bachacou, H. Bachas, K. Bachiu, A. Backman, F. Badea, A. Bagnaia, P. Bahmani, M. Bailey, A.J. Bailey, V.R. Baines, J.T. Bakalis, C. Baker, O.K. Bakker, P.J. Bakos, E. Gupta, D. Bakshi Balaji, S. Balasubramanian, R. Baldin, E.M. Balek, P. Ballabene, E. Balli, F. Baltes, L.M. Balunas, W.K. Balz, J. Banas Department of Physics University of Adelaide Adelaide Australia Department of Physics University of Alberta Edmonton AB Canada Department of Physics Ankara University Ankara Turkey Division of Physics TOBB University of Economics and Technology Ankara Turkey LAPP Université Savoie Mont Blanc CNRS/IN2P3 Annecy France APC Université Paris Cité CNRS/IN2P3 Paris France High Energy Physics Division Argonne National Laboratory Argonne IL United States Department of Physics University of Arizona Tucson AZ United States Department of Physics University of Texas at Arlington Arlington TX United States Physics Department National and Kapodistrian University of Athens Athens Greece Physics Department National Technical University of Athens Zografou Greece Department of Physics University of Texas at Austin Austin TX United States Institute of Physics Azerbaijan Academy of Sciences Baku Azerbaijan Institut de Física d’Altes Energies (IFAE) Barcelona Institute of Science and Technology Barcelona Spain Institute of High Energy Physics Chinese Academy of Sciences Beijing China Physics Department Tsinghua University Beijing China Department of Physics Nanjing University Nanjing China University of Chinese Academy of Science (UCAS) Beijing China Institute of Physics University of Belgrade Belgrade Serbia Department for Physics and Technology University of Bergen Bergen Norway Physics Division Lawrence Berkeley National Laboratory Berkeley CA United States Institut für Physik Humboldt Universität zu Berlin Berlin Germany Albert Einstein Center for Fundamental Physics and Laboratory for High Energy Physics University of Bern Bern Switzerland School of Physics and Astronomy University of Birmingham Birmingham United Kingdom Department of Physics Bogazici University Istanbul Turkey Department of Physics Engineering Gaziantep University Gaziantep Turkey Department of Physics Istanbul University Istanbul Turkey Istinye University Sariyer Istanbul

The need for large-scale production of highly accurate simulated event samples for the extensive physics programme of the ATLAS experiment at the Large Hadron Collider motivates the development of new simulation techniques. Building on the recent success of deep learning algorithms, variational autoencoders and generative adversarial networks are investigated for modelling the response of the central region of the ATLAS electromagnetic calorimeter to photons of various energies. The properties of synthesised showers are compared with showers from a full detector simulation using geant4. Both variational autoencoders and generative adversarial networks are capable of quickly simulating electromagnetic showers with correct total energies and stochasticity, though the modelling of some shower shape distributions requires more refinement. This feasibility study demonstrates the potential of using such algorithms for ATLAS fast calorimeter simulation in the future and shows a possible way to complement current simulation techniques. © The Author(s) 2024.

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Conceptual design and preliminary results of a vr-based radiation safety training system for interventional radiologists

arXiv

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arXiv 2020年

作者： Guo, Yi Mao, Li Zhang, Gongsen Chen, Zhi Pei, Xi Xu, X. George Department of Engineering and Applied Physics University of Science and Technology of China Hefei Anhui230026 China Nuclear Engineering Program Rensselaer Polytechnic Institute TroyNY12180 United States

Recent studies have reported an increased risk of developing brain and neck tumors, as well as cataracts, in practitioners in interventional radiology (IR). Occupational radiation protection in IR has been a top concern for regulatory agencies and professional societies. To help minimize occupational radiation exposure in IR, we conceptualized a virtual reality (VR) based radiation safety training system to help operators understand complex radiation fields and to avoid high radiation areas through game-like interactive simulations. The preliminary development of the system has yielded results suggesting that the training system can calculate and report the radiation exposure after each training session based on a database precalculated from computational phantoms and Monte Carlo simulations and the position information provided in real-time by the MS Hololens headset worn by trainee. In addition, real-time dose rate and cumulative dose will be displayed to the trainee by MS Hololens to help them adjust their practice. This paper presents the conceptual design of the overall hardware and software design, as well as preliminary results to combine MS HoloLens headset and complex 3D X-ray field spatial distribution data to create a mixed reality environment for safety training purpose in IR. Copyright © 2020, The Authors. All rights reserved.

关键词： Conceptual design

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Unveiling the mechanism of phase and morphology selections during the devitrification of Al-Sm amorphous ribbon

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Physical Review Materials 2021年第4期5卷 043402-043402页

作者： Fanqiang Meng Yang Sun Feng Zhang Bo Da Cai-Zhuang Wang Matthew J. Kramer Kai-Ming Ho Dongbai Sun Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen University Zhuhai Guangdong 519082 China Department of Applied Physics and Applied Mathematics Columbia University New York New York 10027 USA Ames Laboratory U.S. Department of Energy and Department of Physics Iowa State University Ames Iowa 50011 USA Research and Services Division of Materials Data and Integrated System National Institute for Materials Science 1-1 Namiki Tsukuba Ibaraki 305-0044 Japan School of Materials Science and Engineering Sun Yat-Sen University Guangzhou 510275 China

The complex interplay between energetic and kinetic factors that governs the phase and morphology selections can originate at the earliest stage of crystallization in the amorphous parent phases. Because of the extreme difficulties in capturing the microscopic nucleation process, a detailed picture of how initial disordered structures affect the transformation pathway remains unclear. Here, we report the experimental observation of widely varying phase selection and grain size evolution during the devitrification of a homogeneous melt-spun glassy ribbon. Two different crystalline phases θ−Al5Sm and ɛ−Al60Sm11 are found to form in the different regions of the same metallic glass (MG) ribbon during the devitrification. The grain size of the ɛ−Al60Sm11 phase shows a strong spatial heterogeneity. The coarse-grained ɛ−Al60Sm11 phase coupled with the small volume fraction of the θ−Al5Sm phase is preferably formed close to the wheel side of the melt-spun ribbon. Combining experimental characterization and computational simulations, we show that phase selection and microstructure evolution can be traced back to different types and populations of atomic clusters that serve as precursors for the nucleation of different crystalline phases. Inhomogeneous cooling rates cause different structure orders across the glass sample during the quenching process. Our findings provide direct insight into the effect of structural order on the crystallization pathways during the devitrification of MG. It also opens an avenue to study the detailed nucleation process at the atomic level using the MG as a platform and suggests the opportunity of microstructure and property design via controlling the cooling process.

关键词： Crystallization Microstructure Nucleation Phase transitions Alloys Metallic glasses Electron microscopy Molecular dynamics

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Quality assurance and quality control of the SiPM production for the DarkSide-20k dark matter experiment

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The European Physical Journal C 2025年第5期85卷 1-22页

作者： Acerbi, F. Adhikari, P. Agnes, P. Ahmad, I. Albergo, S. Albuquerque, I. F. Alexander, T. Alton, A. K. Amaudruz, P. Angiolilli, M. Aprile, E. Atzori Corona, M. Auty, D. J. Ave, M. Avetisov, I. C. Azzolini, O. Back, H. O. Balmforth, Z. Barrado Olmedo, A. Barrillon, P. Batignani, G. Bhowmick, P. Bloem, M. Blua, S. Bocci, V. Bonivento, W. Bottino, B. Boulay, M. G. Buchowicz, A. Bussino, S. Busto, J. Cadeddu, M. Cadoni, M. Calabrese, R. Camillo, V. Caminata, A. Canci, N. Capra, A. Caravati, M. Cardenas-Montes, M. Cargioli, N. Carlini, M. Castello, P. Cavalcante, P. Cebrian, S. Cela Ruiz, J. Chashin, S. Chepurnov, A. Cifarelli, L. Cintas, D. Cleveland, B. Coadou, Y. Cocco, V. Colaiuda, D. Conde Vilda, E. Consiglio, L. Costa, B. S. Czubak, M. D’Auria, S. Da Rocha Rolo, M. D. Darbo, G. Davini, S. de As mundis, R. De Cecco, S. Dellacasa, G. Derbin, A. V. Capua, F. Di Noto, L. Di Stefano, P. Di Dias, L. K. Dionisi, C. Dolganov, G. Dordei, F. Dronik, V. Elersich, A. Ellingwood, E. Erjavec, T. Fearon, N. Fernandez Diaz, M. Ficorella, A. Fiorillo, G. Franchini, P. Franco, D. Frandini Gatti, H. Frolov, E. Gabriele, F. Gahan, D. Galbiati, C. Galiski, G. Gallina, G. Gallus, G. Garbini, M. Garcia Abia, P. Gawdzik, A. Gendotti, A. Giovanetti, G. K. Goicoechea Casanueva, V. Gola, A. Grandi, L. Grauso, G. Grilli di Cortona, G. Grobov, A. Gromov, M. Gulino, M. Guo, C. Hackett, B. R. Hallin, A. Hamer, A. Haranczyk, M. Hessel, T. Horikawa, S. Hu, J. Hubaut, F. Hucker, J. Hugues, T. Hungerford, E. V. Ianni, A. Ippoliti, G. Ippolito, V. Jamil, A. Jillings, C. Keloth, R. Kemmerich, N. Kemp, A. Kester, Carlos E. Kimura, M. Kondo, K. Korga, G. Kotsiopoulou, L. Koulosousas, S. Kubankin, A. Kunze, P. Kuss, M. Kuźniak, M. Kuzwa, M. La Commara, M. Lai, M. Le Guirriec, E. Leason, E. Leoni, A. Lidey, L. Lissia, M. Luzzi, L. Lychagina, O. Macfadyen, O. Machulin, I. N. Manecki, S. Manthos, I. Marasciulli, A. Margutti, G. Mari, S. M. Mariani, C. Maricic, J. Martinez, M. Martoff, C. J. Matteucci, G. Mavrokoridis, K. Mazza, E. McDonald, A. B. Merzi, S Fondazione Bruno Kessler Povo Italy Department of Physics Carleton University Ottawa Canada Gran Sasso Science Institute L’Aquila Italy INFN Laboratori Nazionali del Gran Sasso Assergi (AQ) Italy AstroCeNT Nicolaus Copernicus Astronomical Center of the Polish Academy of Sciences Warsaw Poland INFN Catania Catania Italy Università of Catania Catania Italy Instituto de Física Universidade de SËœao Paulo São Paulo Brazil Pacific Northwest National Laboratory Richland USA Physics Department Augustana University Sioux Falls USA TRIUMF Vancouver Canada Physics Department Columbia University New York USA INFN Cagliari Cagliari Italy Physics Department Università degli Studi di Cagliari Cagliari Italy Department of Physics University of Alberta Edmonton Canada Mendeleev University of Chemical Technology Moscow Russia INFN Laboratori Nazionali di Legnaro Legnaro (Padova) Italy Savannah River National Laboratory Jackson USA Institute of Experimental Physics University of Hamburg Hamburg Germany CIEMAT Centro de Investigaciones Energéticas Medioambientales y Tecnológicas Madrid Spain Centre de Physique des Particules de Marseille Aix Marseille Univ CNRS/IN2P3 CPPM Marseille France INFN Pisa Pisa Italy Physics Department Università degli Studi di Pisa Pisa Italy University of Oxford Oxford UK Science and Technology Facilities Council (STFC) Rutherford Appleton Laboratory Technology Didcot UK INFN Torino Turin Italy Department of Electronics and Telecommunications Politecnico di Torino Turin Italy INFN Sezione di Roma Rome Italy Physics Department Università degli Studi di Genova Genoa Italy INFN Genova Genoa Italy Institute of Radioelectronics and Multimedia Technology Warsaw University of Technology 00-661 Poland INFN Roma Tre Rome Italy INFN Napoli Naples Italy Physics Department Università degli Studi “Federico II” di Napoli Naples Italy Virginia Tech Blacksburg USA Department of Electrical and Electronic Engineering Universita‘ deg

DarkSide-20k is a novel liquid argon dark matter detector currently under construction at the Laboratori Nazionali del Gran Sasso (LNGS) of the Istituto Nazionale di Fisica nucleare (INFN) that will push the sensitivity for Weakly Interacting Massive Particle (WIMP) detection into the neutrino fog. The core of the apparatus is a dual-phase Time Projection Chamber (TPC), filled with 50 tonnes of low radioactivity underground argon (UAr) acting as the WIMP target. NUV-HD-cryo Silicon Photomultipliers (SiPM)s designed by Fondazione Bruno Kessler (FBK) (Trento, Italy) were selected as the photon sensors covering two $$10.5~\text {m}^2$$ Optical Planes, one at each end of the TPC, and a total of $$5~\text {m}^2$$ photosensitive surface for the liquid argon veto detectors. This paper describes the Quality Assurance and Quality Control (QA/QC) plan and procedures accompanying the production of FBK NUV-HD-cryo SiPM wafers manufactured by LFoundry s.r.l. (Avezzano, AQ, Italy). SiPM characteristics are measured at 77 K at the wafer level with a custom-designed probe station. As of March 2025, 1314 of the 1400 production wafers (94% of the total) for DarkSide-20k were tested. The wafer yield is $$93.2\pm 2.5$$ %, which exceeds the 80% specification defined in the original DarkSide-20k production plan.

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Electron spin dynamics guide cell motility

arXiv

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arXiv 2025年

作者： Wang, Kai Gilmer, Gabrielle Araña, Matheus Cândia Iijima, Hirotaka Bergmann, Juliana Woollard, Antonio Mesits, Boris McGraw, Meghan Zoltowski, Brian Cappellaro, Paola Ungar, Alex Pekker, David Waldeck, David H. Saxena, Sunil Lloyd, Seth Ambrosio, Fabrisia Discovery Center for Musculoskeletal Recovery Schoen Adams Research Institute at Spaulding BostonMA United States Department of Physical Medicine & Rehabilitation Spaulding Rehabilitation Hospital BostonMA United States Department of Physical Medicine & Rehabilitation Harvard Medical School BostonMA United States Cellular and Molecular Pathology Graduate Program University of Pittsburgh PittsburghPA United States Medical Scientist Training Program School of Medicine University of Pittsburgh PittsburghPA United States École Polytechnique Institut Polytechnique de Paris Palaiseau France Department of Physics & Astronomy University of Pittsburgh PittsburghPA United States Department of Chemistry Southern Methodist University DallasTX United States Department of Nuclear Science and Engineering Massachusetts Institute of Technology CambridgeMA02139 United States Department of Physics Massachusetts Institute of Technology CambridgeMA02139 United States Department of Chemistry University of Pittsburgh PittsburghPA United States Department of Mechanical Engineering Massachusetts Institute of Technology BostonMA United States

Diverse organisms exploit the geomagnetic field (GMF) for migration. Migrating birds employ an intrinsically quantum mechanical mechanism for detecting the geomagnetic field: absorption of a blue photon generates a radical pair whose two electrons precess at different rates in the magnetic field, thereby sensitizing cells to the direction of the GMF. In this work, using an in vitro injury model, we discovered a quantum-based mechanism of cellular migration. Specifically, we show that migrating cells detect the GMF via an optically activated, electron spin-based mechanism. Cell injury provokes acute emission of blue photons, and these photons sensitize muscle progenitor cells to the magnetic field. We show that the magnetosensitivity of muscle progenitor cells is (a) activated by blue light, but not by green or red light, and (b) disrupted by the application of an oscillatory field at the frequency corresponding to the energy of the electron-spin/magnetic field interaction. A comprehensive analysis of protein expression reveals that the ability of blue photons to promote cell motility is mediated by activation of calmodulin calcium sensors. Collectively, these data suggest that cells possess a light-dependent magnetic compass driven by electron spin dynamics. © 2025, CC BY.

关键词： Spin dynamics

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Electronic Structure of Superconducting Infinite-Layer Lanthanum Nickelates

arXiv

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arXiv 2024年

作者： Sun, Wenjie Jiang, Zhicheng Xia, Chengliang Hao, Bo Li, Yueying Yan, Shengjun Wang, Maosen Liu, Hongquan Ding, Jianyang Liu, Jiayu Liu, Zhengtai Liu, Jishan Chen, Hanghui Shen, Dawei Nie, Yuefeng National Laboratory of Solid State Microstructures Jiangsu Key Laboratory of Artificial Functional Materials College of Engineering and Applied Sciences Nanjing University Nanjing210093 China Collaborative Innovation Center of Advanced Microstructures Nanjing University Nanjing210093 China National Synchrotron Radiation Laboratory School of Nuclear Science and Technology University of Science and Technology of China Hefei230026 China NYU-ECNU Institute of Physics NYU Shanghai Shanghai200122 China Department of Physics Southern University of Science and Technology Shenzhen518055 China Department of Physics Brown University ProvidenceRI02912 United States National Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai200050 China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai201210 China Department of Physics New York University New YorkNY10012 United States

Revealing the momentum-resolved electronic structure of infinite-layer nickelates is essential for understanding this new class of unconventional superconductors, but has been hindered by the formidable challenges in improving the sample quality. In this work, we report for the first time the angle-resolved photoemission spectroscopy of superconducting La0.8Sr0.2NiO2 films prepared by molecular beam epitaxy and in situ atomic-hydrogen reduction. The measured Fermi topology closely matches theoretical calculations, showing a large Ni-dx2-y2 derived Fermi sheet that evolves from hole-like to electron-like along kz, and a three-dimensional (3D) electron pocket centered at Brillouin zone corner. The Ni-dx2-y2 derived bands show a mass enhancement (m*/mDFT) of 2-3, while the 3D electron band shows negligible band renormalization. Moreover, the Ni-dx2-y2 derived states also display a band dispersion anomaly at higher binding energy, reminiscent of the waterfall feature and kinks observed in cuprates. © 2024, CC BY.

关键词： Electronic structure

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Learning to learn: Non-equilibrium design protocols for adaptable materials

arXiv

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arXiv 2022年

作者： Falk, Martin J. Wu, Jiayi Matthews, Ayanna Sachdeva, Vedant Pashine, Nidhi Gardel, Margaret Nagel, Sidney Murugan, Arvind Department of Physics The University of Chicago ChicagoIL60637 United States Graduate Program in Biophysical Sciences The University of Chicago ChicagoIL60637 United States School of Engineering and Applied Science Yale University New HavenCT06511 United States James Franck Institute The University of Chicago ChicagoIL60637 United States Institute for Biophysical Dynamics The University of Chicago ChicagoIL60637 United States Pritzker School of Molecular Engineering The University of Chicago ChicagoIL60637 United States

Evolution in time-varying environments naturally leads to adaptable biological systems that can easily switch functionalities. Advances in the synthesis of environmentally-responsive materials therefore open up the possibility of creating a wide range of synthetic materials which can also be trained for adaptability. We consider high-dimensional inverse problems for materials where any particular functionality can be realized by numerous equivalent choices of design parameters. By periodically switching targets in a given design algorithm, we can teach a material to perform incompatible functionalities with minimal changes in design parameters. We exhibit this learning strategy for adaptability in two simulated settings: elastic networks that are designed to switch deformation modes with minimal bond changes;and heteropolymers whose folding pathway selections are controlled by a minimal set of monomer affinities. The resulting designs can reveal physical principles, such as nucleation-controlled folding, that enable adaptability. © 2022, CC BY.

关键词： Inverse problems

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Performance evaluation of the modular J-PET detector in conventional PET imaging

Performance evaluation of the modular J-PET detector in conv...

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IEEE Symposium on nuclear science (NSS/MIC)

作者： M. Das R. Bayerlein S. Parzych S. Sharma R. D. Badawi E. Y. Beyene E. Czerwiński A. Hubalewska-Dydejczyk T. Kaplanoglu G. Korcyl W. Krzemien W. Mryka S. Niedźwiecki M. Opalińska M. Rädler M. Skurzok B. A Spencer P. Tanty K. Tayefi Ardebili P. Moskal E.Ł. Stepien Doctoral School of Exact and Natural Sciences Jagiellonian University M. Smoluchowski Institute of Physics S. Łojasiewicza 11 30-348 Krakow Poland Department of Biomedical Engineering University of California Davis Sacramento California United States of America Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University Krakow Poland Centre for Theranostics Jagiellonian University Jagiellonian University Kopernika 40 31-501 Krakow Poland Department of Radiology University of California Davis Sacramento California United States of America Chair and Department of Endocrinology Jagiellonian University Medical College Krakow Poland High Energy Department National Centre for Nuclear Research Otwock Swierk Poland

ISBN: (数字)9798350388152

ISBN: (纸本)9798350388169

The utilization of organic scintillator strips in the construction of J-PET represents a remarkable departure from the conventional PET methodology that relies on inorganic crystal scintillators [1, 2]. This innovative approach not only holds the potential for cost-effectiveness but also facilitates the development of stand-alone detection modules, making PET imaging accessible to non-specialized laboratories [3]. The J-PET scanner, recently commissioned for research imaging on clinical patients at the University Hospital in Krakow, has undergone rigorous evaluation. This work is based on the study in which a single-bed position scan was performed on patients injected with [$\left.{ }^{68} \mathrm{Ga}\right]$-DOTA-TATE. This study evaluates the performance of human imaging in J-PET with particular attention to incorporating various corrections, including attenuation, normalization, random and scatter corrections. Attenuation correction was applied using the kVp-dependent transformation [4]. Normalization corrections were calculated using the component-based approach [5]. Random coincidences were corrected using the delayed time window method [6]. A Monte Carlo-based scatter correction (SC) method was implemented using SimSET to simulate the scatter contribution and calculate the SC factors in between each OSEM iteration of the image reconstruction [7]. In this contribution, the reconstructed images of patients scanned with the JPET, the first scanner based on plastic scintillators, and supplemented with the necessary corrections, will be presented.

关键词： Performance evaluation Strips Microwave integrated circuits Scintillators Monte Carlo methods Semiconductor detectors Attenuation

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Evaluating 3D Gamma-ray Imaging Techniques for Distributed Sources at the Fukushima Daiichi nuclear Power Station

Evaluating 3D Gamma-ray Imaging Techniques for Distributed S...

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2020 IEEE nuclear science Symposium and Medical Imaging Conference, NSS/MIC 2020

作者： Knecht, K. Hellfeld, D. Pavlovsky, R. Quiter, B. Joshi, T.H.Y. Torii, T. Furuta, Y. Vetter, K. The Nuclear Engineering Department The University of California Berkeley BerkeleyCA94720 United States The Applied Nuclear Physics Program Lawrence Berkeley National Laboratory BerkeleyCA94720 United States The Collaborative Laboratories for Advanced Decommissioning Science Japan Atomic Energy Agency 790-1 Motooka aza Ohtsuka Tomioka-machi Futaba-gun Fukushima979-1151 Japan

ISBN: (纸本)9781728176932

Portable radiation detection systems can be equipped with contextual sensors to allow free-moving 3D gamma-ray source mapping and imaging through a method called scene data fusion (SDF). The scene information provided by the contextual sensors can be used to enable 3D mapping and constrain gamma-ray image reconstruction to improve accuracy and computational efficiency. SDF can be a useful tool in a wide range of radiological and nuclear safety and security applications such as radiation mapping for contamination remediation. To demonstrate SDF for this application, Polaris-LAMP, a commercially available detector that has been integrated with contextual sensors, was hand-carried in a parking lot containing vehicles used during remediation efforts following the March 2011 Fukushima Daiichi nuclear Power Station accident. In order to detect and map potential contamination of the vehicles, proximity mapping and Compton imaging techniques have been applied to data collected over a series of short measurements, each covering different areas of the parking lot. Proximity mapping successfully identified which vehicles are contaminated, but Compton imaging further improved localization of intensity to key vehicle features on top of distributed contamination, demonstrating the utility of SDF in radiation mapping of unknown distributed source environments. Methods to stitch multiple reconstructions together were also developed, allowing the creation of large area radiation maps that are globally consistent. The work presented here illustrates the utility of SDF with an contextual-sensor enhanced commercial radiation detection and imaging system deployed in a hand-portable format to effectively map extended areas and localize radiological contamination within minutes which is impossible to achieve with conventional means with hand-portable radiation detectors or statically deployed gamma-ray imagers. © 2020 IEEE

关键词： Contamination

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New insights into radiation damage in additively manufactured alloy 718

引用

Additive Manufacturing 2025年 108卷

作者： Huayan Hu Tianji Zhao Donghai Du Xianglong Guo Hefei Huang Chenyang Lu Miao Song School of Nuclear Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China Institute of Clean Energy Yangtze Delta Research Institute Northwestern Polytechnical University Taicang 215400 China Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China Department of Nuclear Science and Technology Xi’an Jiaotong University Xi’an 710049 China

Alloy 718 is one of the microstructural complex materials used in nuclear reactors. Additive manufacturing offers new deployment options but introduces unique structural features that complicate radiation damage behaviors, which remains largely unexplored. Here, we investigated the impacts of dislocation cells, cell boundary segregation, and precipitation on radiation damage in seven structural variants of additively manufactured (AM) 718 through thermal separation. Annealing isolated as-built dislocation cells and cell boundary segregation, while thermal aging incorporated γ'/γ″ nanoprecipitates or δ phase. These variants were then subjected to 1 MeV He + ion irradiation at 400, 500, and 600 ℃ to a fluence of 5 × 10 16 ions/cm 2 . Results show that dislocation cells and dislocations in AM variants effectively absorbed interstitial clusters and delayed Frank loop evolution. However, cell boundaries, exhibiting an interstitial bias, accelerated helium swelling. Among the various variables, the matrix Nb and Ti contents have the most significant effect on helium swelling. High Nb and Ti levels enhance defect trapping, which bind vacancies and promote defect recombination, reducing steady-state defect concentrations and delaying defect evolution. In contrast, Nb and Ti depletions, either due to segregation or γ′/γ″ and δ precipitations, accelerate dislocation loop formation and helium swelling, with δ-containing samples exhibiting the most severe effects. The as-built 718 alloy exhibited lower loop formation incubation dose and increased swelling compared to recrystallized counterpart. Thermal-aged variants with γ'/γ″ and δ precipitates promoted loop evolution and swelling compared to non-aged variants. Therefore, AM 718 is recommended to be homogenized or recrystallized for solution-annealed variant and avoid δ precipitation for precipitation-hardened variant. This is an initial study using thermal separation to clarify the individual impacts of dislocation cells, seg

关键词： Additive manufacturing Alloy 718 Dislocation cell Irradiated microstructure Irradiation effect

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