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Reprocessing the NEAT Dataset: Preliminary Results

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arXiv 2025年

作者： Nugent, C.R. Bauer, J.M. Benitez, O. Blain, M. D’Souza, N. Garimella, S. Goldwater, M. Kim, Y. Larsen, H.C.G. Linder, T. Mackowiak, K. McGinnis, Z. Pan, E. Pedersen, C.C. Sadhwani, P. Spoto, F. Tan, N.J. Vereš, P. Xue, C. Olin College of Engineering 1000 Olin Way NeedhamMA02492 United States Department of Astronomy University of Maryland College ParkMD20742 United States Department of Earth and Space Sciences College of the Canyons Santa ClaritaCA91355 United States MIT-WHOI Joint Program in Applied Ocean Science & Engineering Cambridge and Woods Hole MA United States Department of Applied Ocean Physics & Engineering Woods Hole Oceanographic Institution 266 Woods Hole Road MS #55 Woods HoleMA02543-1050 United States Aalborg University Fibigerstræde 16 Aalborg9220 Denmark Planetary Science Institute TucsonAZ85719 United States Minor Planet Center Smithsonian Astrophysical Observatory 60 Garden Street CambridgeMA02138 United States School of Physical and Chemical Sciences Te Kura Matū University of Canterbury Private Bag 4800 Christchurch8140 New Zealand

We have created a new image analysis pipeline to reprocess images taken by the Near Earth Asteroid Tracking survey and have applied it to ten nights of observations. This work is the first large-scale reprocessing of images from an asteroid discovery survey in which thousands of archived images are re-calibrated, searched for minor planets, and resulting observations are reported to the Minor Planet Center. We describe the software used to extract, calibrate, and clean sources from the images, including specific techniques that accommodate the unique features of these archival images. This pipeline is able to find fainter asteroids than the original pipeline. © 2025, CC BY.

关键词： Asteroids

Torsional periodic lattice distortions and diffraction of twisted 2D materials

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arXiv 2022年

作者： Sung, Suk Hyun Goh, Yin Min Yoo, Hyobin Engelke, Rebecca Xie, Hongchao Zhang, Kuan Li, Zidong Ye, Andrew Deotare, Parag B. Tadmor, Ellad B. Mannix, Andrew J. Park, Jiwoong Zhao, Liuyan Kim, Philip Hovden, Robert Department of Materials Science and Engineering University of Michigan Ann ArborMI48109 United States Department of Physics University of Michigan Ann ArborMI48109 United States Department of Physics Sogang University Seoul04107 Korea Republic of Department of Physics Harvard University CambridgeMA02138 United States Aerospace Engineering and Mechanics University of Minnesota MinneapolisMN55455 United States Electrical and Computer Engineering Department University of Michigan Ann ArborMI48109 United States Pritzker School of Molecular Engineering University of Chicago ChicagoIL60637 United States Applied Physics Program University of Michigan Ann ArborMI48109 United States Department of Materials Science and Engineering Stanford University StanfordCA94305 United States Department of Chemistry University of Chicago ChicagoIL60637 United States

Twisted 2D materials form complex moiré structures that spontaneously reduce symmetry through picoscale deformation within a mesoscale lattice. We show twisted 2D materials contain a torsional displacement field comprised of three transverse periodic lattice distortions (PLD). The torsional PLD amplitude provides a single order parameter that concisely describes the structural complexity of twisted bilayer moirés. Moreover, the structure and amplitude of a torsional periodic lattice distortion is quantifiable using rudimentary electron diffraction methods sensitive to reciprocal space. In twisted bilayer graphene, the torsional PLD begins to form at angles below 3.89° and the amplitude reaches 8 pm around the magic angle of 1. 1°. At extremely low twist angles (e.g. below 0.25°) the amplitude increases and additional PLD harmonics arise to expand Bernal stacked domains separated by well defined solitonic boundaries. The torsional distortion field in twisted bilayer graphene is analytically described and has an upper bound of 22.6 pm. Similar torsional distortions are observed in twisted WS2, CrI3, and WSe2/MoSe2 © 2022, CC BY.

关键词： Graphene

Design Considerations for 3D Position Sensitive Scintillation Detectors that Achieve 100 ps Coincidence Time Resolution

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Design Considerations for 3D Position Sensitive Scintillatio...

IEEE Symposium on nuclear science (NSS/MIC)

作者： Shirin Pourashraf Zhixiang Zhao Andrea Gonzalez - Montoro Joshua W. Cates Jun Yeon Won Jae Sung Lee Craig S. Levin Department of Radiology Stanford University Stanford CA USA School of Biomedical Engineering Shanghai Jiao Tong University Shanghai People’s Republic of China Applied Nuclear Physics Program Lawrence Berkeley National Laboratory Berkeley CA USA Department of Nuclear Medicine and Biomedical Sciences Seoul National University Seoul South Korea Departments of Radiology Bioengineering Physics and Electrical Engineering Molecular Imaging Program Stanford University Stanford CA USA

ISBN: (数字)9781665421133

ISBN: (纸本)9781665421140

We have studied design considerations for three dimension positioning sensitive (3DPS) scalable TOF- PET detectors that achieve 100 ps coincidence time resolution (CTR). These scintillation detectors are based on 3×3×10 mm³ “LGSO” crystals side- coupled to arrays of 3×3 mm 2 SiPMs. A CPLD is used to provide 3 mm positioning resolution along the length of each crystal element. Revised mixed-signal front-end electronics decreased the power dissipation by 200% and increased the detector packing fraction while preserving the CTR performance. A low timing jitter FPGA-based TDC was used for data acquisition of the timing channels. Measured CTR was 102.2 ± 1.3 ps FWHM using a 22Na point source.

关键词： Timing jitter Three-dimensional displays Image resolution Data acquisition Detectors Crystals Timing

State-selective single-electron capture in intermediate-energy C4+ + He collisions

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Physical Review A 2021年第3期103卷 032827-032827页

作者： D. L. Guo J. W. Gao S. F. Zhang X. L. Zhu Y. Gao D. M. Zhao R. T. Zhang Y. Wu J. G. Wang A. Dubois X. Ma Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China GSI Helmholtzzentrum für Schwerionenforschung D-64291 Darmstadt Germany School of Nuclear Science and Technology University of Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Radiation Physics and Technology of Ministry of Education Institute of Nuclear Science and Technology Sichuan University Chengdu 610064 China Laser Fusion Research Center China Academy of Engineering Physics Mianyang 621900 China Institute of Applied Physics and Computational Mathematics Beijing 100088 China Center for Applied Physics and Technology HEDPS and School of Physics Peking University Beijing 100871 China Sorbonne Université CNRS Laboratoire de Chimie Physique-Matière et Rayonnement F-75005 Paris France

A combined experimental and theoretical study on single capture in 15–50keV/uC4+ + He collisions was performed. State-selective single-electron capture cross sections and projectile scattering angle distributions were obtained by using a reaction microscope. A comparison of the state-selective cross sections with theoretical calculations based on the two-active-electron semiclassical atomic-orbital close-coupling method showed an excellent agreement for the considered impact energies. For the angular differential cross sections, an overall agreement was also obtained between the present experimental and theoretical results. Simulations performed using an extended Fraunhofer-type diffraction model suggest that the undulatory structures observed at small scattering angles for capture to C3+(1s22s) and C3+(1s22p0) can be interpreted as the diffraction pattern of the incident projectile de Broglie wave confined by an aperture defined as the region around the target where the considered capture process is likely. The strong competition between single-electron capture to C3+(1s22p0) and C3+(1s22p1) is also discussed to interpret the differences observed between their respective differential cross sections.

关键词： Atomic & molecular collisions Charge-transfer collisions

Testing the data framework for an AI algorithm in preparation for high data rate X-ray facilities

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arXiv 2022年

作者： Chen, Hongwei Chitturi, Sathya R. Plumley, Rajan Shen, Lingjia Drucker, Nathan C. Burdet, Nicolas Peng, Cheng Mardanya, Sougata Ratner, Daniel Mishra, Aashwin Yoon, Chun Hong Song, Sanghoon Chollet, Matthieu Fabbris, Gilberto Dunne, Mike Nelson, Silke Li, Mingda Lindenberg, Aaron Jia, Chunjing Nashed, Youssef Bansil, Arun Chowdhury, Sugata Feiguin, Adrian E. Turner, Joshua J. Thayer, Jana B. Linac Coherent Light Source Slac National Accelerator Laboratory Menlo Park United States Stanford Institute for Materials and Energy Sciences Stanford University Stanford United States Department of Materials Science and Engineering Stanford University Stanford United States Department of Physics Northeastern University Boston United States Department of Physics Carnegie Mellon University Pittsburgh United States School of Engineering and Applied Sciences Harvard University Cambridge United States Department of Physics and Astrophysics Howard University Washington United States Advanced Photon Source Argonne National Laboratory Argonne United States Department of Nuclear Science & Engineering The Massachusetts Institute of Technology Cambridge United States

The advent of next-generation X-ray free electron lasers will be capable of delivering X-rays at a repetition rate approaching 1 MHz continuously. This will require the development of data systems to handle experiments at these type of facilities, especially for high throughput applications, such as femtosecond X-ray crystallography and X-ray photon fluctuation spectroscopy. Here, we demonstrate a framework which captures single shot X-ray data at the LCLS and implements a machine-learning algorithm to automatically extract the contrast parameter from the collected data. We measure the time required to return the results and assess the feasibility of using this framework at high data volume. We use this experiment to determine the feasibility of solutions for 'live' data analysis at the MHz repetition rate. © 2022, CC BY.

关键词： Machine learning

Improved measurements of neutron lifetime with cold neutron beam at J-PARC

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arXiv 2024年

作者： Fuwa, Y. Hasegawa, T. Hirota, K. Hoshino, T. Hosokawa, R. Ichikawa, G. Ieki, S. Ino, T. Iwashita, Y. Kitaguchi, M. Kitahara, R. Makise, S. Mishima, K. Mogi, T. Nagakura, N. Oide, H. Okabe, H. Otono, H. Seki, Y. Sekiba, D. Shima, T. Shimizu, H.E. Shimizu, H.M. Sumi, N. Sumino, H. Tanida, M. Uehara, H. Yamada, T. Yamashita, S. Yano, K. Yoshioka, T. Japan Atomic Energy Agency Tokai319-1195 Japan J-PARC Center Tokai319-1195 Japan Department of Physics Graduate School of Science Nagoya University Nagoya464-8602 Japan High Energy Accelerator Research Organization Tsukuba305-0801 Japan Department of Physics Graduate School of Science Kyushu University Fukuoka819-0395 Japan Faculty of Science and Engineering Iwate University Morioka020-8551 Japan Department of Physics Graduate School of Science The University of Tokyo Tokyo113-0033 Japan Institute for Integrated Radiation and Nuclear Science Kyoto University Osaka590-0494 Japan Kobayashi-Maskawa Institute Nagoya University Nagoya464-8602 Japan Department of Physics Kyoto University Kyoto606-8502 Japan Technology Research Center Sumitomo Heavy Industries Ltd. Yokosuka237-8555 Japan Department of Physics Fuculty of Sciences Kyushu University Fukuoka819-0395 Japan Institute of Multidisciplinary Research for Advanced Materials Tohoku University Sendai980-8577 Japan Institute of Applied Physics University of Tsukuba Tsukuba305-8573 Japan Research Center for Nuclear Physics Osaka University Ibaraki567-0047 Japan SOKENDAI Shonan Village Hayama240-0193 Japan Research Center for Advanced Science and Technology The University of Tokyo Tokyo153-0041 Japan Research and Regional Cooperation Office Iwate Prefectural University Takizawa020-0693 Japan Research Center for Advanced Particle Physics Kyushu University Fukuoka819-0395 Japan

The "neutron lifetime puzzle" arises from the discrepancy between neutron lifetime measurements obtained using the beam method, which measures decay products, and the bottle method, which measures the disappearance of neutrons. To resolve this puzzle, we conducted an experiment using a pulsed cold neutron beam at J-PARC. In this experiment, the neutron lifetime is determined from the ratio of neutron decay counts to 3He(n,p)3H reactions in a gas detector. This experiment belongs to the beam method but differs from previous experiments that measured protons, as it instead detects electrons, enabling measurements with distinct systematic uncertainties. By enlarging the beam transport system and reducing systematic uncertainties, we achieved a fivefold improvement in precision. Analysis of all acquired data yielded a neutron lifetime of τn = 877.2 ± 1.7(stat.)+4−306(sys.) s. This result is consistent with bottle method measurements but exhibits a 2.3σ tension with the average value obtained from the proton-detection-based beam method. © 2024, CC BY.

关键词： Bottles

Electrochemical detection of antimalarial drug (Amodiaquine) using Dy-MOF@MWCNTs composites to prevent erythrocytic stages of plasmodium species in human bodies

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Microchemical Journal 2024年 202卷

作者： Peter, X. Thatheyus Kuo, Chih-Yu Malar, P. Govindasamy, Mani Rajaji, Umamaheswari Yusuf, Kareem Thinfilm Photovoltaics Laboratory Department of Physics and Nanotechnology SRM Institute of Science and Technology Tamil Nadu Kattankulathur 603203 India Department of Chemical Engineering and Biotechnology National Taipei University of Technology Taipei Taiwan International Ph.D. Program in Innovative Technology of Biomedical Engineering and Medical Devices Ming Chi University of Technology New Taipei City 243303 Taiwan Research Center for Intelligence Medical Devices Ming Chi University of Technology New Taipei City 243303 Taiwan Centre for Applied Research Saveetha School of Engineering Saveetha Institute of Medical and Technical Sciences (SIMATS) Tamil Nadu Chennai 602105 India Department of Chemistry College of Science King Saud University Riyadh 11451 Saudi Arabia

Herein, we report on fabrication of dysprosium-based metal–organic framework (Dy-MOF)@multiwalled carbon nanotubes (MWCNT) composites modified with glassy carbon electrode (Dy-MOF@MWCNT/GC) as a working electrode for Antimalarial drug detection. Dy-MOF@MWCNT composites was prepared by sonochemical process along with ultrasonication. The composite structure, phase purity, morphology and composition of the composites were confirmed by X-ray diffraction, Scanning electron microscope, and X-ray photoelectron spectroscopy. Further, Dy@MWCNT composites were deposited on a glassy carbon electrode by drop casting method, and used as an electrode material to efficiently detect Amodiaquine (ADD) by electrochemical techniques such as CV and DPV. The as-prepared Dy@MWCNT composite material showed the oxidation peak current of ADD to be ∼ 60 % higher than other unmodified GC electrodes and showed a low charge transfer resistance (R_ct) of 24 Ω. The Dy@MWCNT provided a broad linear range of 0.4 to 20 µM with a limit of detection of 0.377 μM and sensitivity of 1.817 μA.μM⁻¹ for the detection of ADD. According to the pH study, the amount of electrons and protons involved in the electrochemical processes of ADD was calculated and a plausible mechanism for ADD electro-oxidation was proposed. Thus, the prepared sensor exhibited practical usefulness by determining the ADD drug in human urine samples. Hence, the results shows that the Dy@MWCNT- modified sensor has good electrocatalytic activity for the redox of ADD. © 2024 Elsevier B.V.

关键词： Amodiaquine Antimalarial drug Carbon nanomaterials Electrochemical sensor Metal organic framework

Manipulation of the nanoscale heliconical structure of a twist-bend nematic material with polarized light

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Physical Review Research 2020年第3期2卷 032004(R)-032004(R)页

作者： C. Feng J. Feng R. Saha Y. Arakawa J. Gleeson S. Sprunt C. Zhu A. Jákli Chemical Physics Interdisciplinary Program Advanced Materials and Liquid Crystal Institute Kent State University Kent Ohio 44242 USA Advanced Light Source Lawrence Berkeley National Lab Berkeley California 94720 USA Department of Physics Kent State University Kent Ohio 44242 USA Department of Applied Chemistry and Life Science Graduate School of Engineering Toyohashi University of Technology Toyohashi 441-8580 Japan

The effect of polarized violet light on the alignment and the heliconical pitch of a liquid crystal dimer containing both sulfur atoms and an azo linkage has been studied by tender resonant x-ray scattering. The results provide evidence of the manipulation of the nanoscale heliconical structure by polarized light. In addition to the bulk alignment of the heliconical nanostructure, the value of the heliconical pitch can be varied as well. After turning the light on, an increase of the pitch is observed in two steps. The increase with a subsecond timescale is attributed to the reduced heliconical order related to trans-cis photoisomerization. This is followed by a smaller increase over a 10-s timescale, which is likely related to the annihilation of defects. After turning the light off, the pitch first decreases within a few seconds to a value larger than the original (before illumination), and then relaxes further on a much longer (hours) timescale.

关键词： Chiral symmetry Dynamical phase transitions Twist deformation

Automatic Hologram Acquisition of Pt Catalyst Nanoparticles on TiO2 Using Particle Detection with Image Processing and AI Classification

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Microscopy and Microanalysis 2021年第S1期27卷 252-253页

作者： Fumiaki Ichihashi Akira Koyama Tetsuya Akashi Shoko Miyauchi Ken'ichi Morooka Hajime Hojo Hisahiro Einaga Toshiaki Tanigaki Hiroyuki Shinada Yasukazu Murakami Hitachi Ltd. Saitama Japan Department of Applied Quantum Physics and Nuclear Engineering Kyushu University Fukuoka Japan Research & Development Group Hitachi Ltd. Hatoyama Saitama Japan Graduate School of Information Science and Electrical Engineering Kyushu University Fukuoka Japan Graduate School of Natural Science and Technology Okayama University Okayama Japan Department of Materials Science Faculty of Engineering Sciences Kyushu University Fukuoka Japan Research & Development Group Hitachi Ltd. Saitama Japan