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Dijet azimuthal correlations in p-p and p-Pb collisions at forward LHC calorimeters

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arXiv 2022年

作者： Al-Mashad, M. Abdullah van Hameren, A. Kakkad, H. Kotko, P. Kutak, Krzysztof Marek van Mechelen, P. Sapeta, S. Department of Physics Faculty of Science Fayoum63514 Egypt Antwerp University Particle Physics group Groenenborgerlaan 171 Antwerpen2020 Belgium Institute of Nuclear Physics Polish Academy of Sciences Radzikowskiego 152 Kraków31-342 Poland AGH University Of Science and Technology Faculty of Physics and Applied Computer Science al. Mickiewicza 30 Kraków30-059 Poland Brookhaven National Laboratory Physics Department Bldg. 510A 20 Pennsylvania Street 30-059 UptonNY11973 United States

We present a state-of-the-art computation for the production of forward dijets in proton-proton and proton-lead collisions at the LHC, in rapidity domains covered by the ATLAS calorimeter and the planned FoCal extension of the ALICE detector. We use the small-x improved TMD (ITMD) formalism, together with collinearly improved TMD gluon distributions and full b-space Sudakov resummation, and discuss nonperturbative corrections due to hadronization and showers using the Pythia event generator. We observe that forward dijets in proton-nucleus collisions at moderately low pT are excellent probes of saturation effects, as the Sudakov resummation does not alter the suppression of the cross section. Copyright © 2022, The Authors. All rights reserved.

关键词： Calorimeters

Beyond circular-arc graphs - recognizing lollipop graphs and medusa graphs

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arXiv 2022年

作者： Çağirici, Deniz Ağaoğlu Çağirici, Onur Derbisz, Jan Hartmann, Tim A. Hliněný, Petr Kratochvíl, Jan Krawczyk, Tomasz Zeman, Peter Masaryk University Brno Czech Republic Toronto Metropolitan University Toronto Canada Theoretical Computer Science Department Faculty of Mathematics and Computer Science Jagiellonian University Kraków Poland RWTH Aachen University Aachen Germany Department of Applied Mathematics Faculty of Mathematics and Physics Charles University Prague Czech Republic Institut de Mathématiques University of Neuchâtel Switzerland

In 1992 Biró, Hujter and Tuza introduced, for every fixed connected graph H, the class of H-graphs, defined as the intersection graphs of connected subgraphs of some subdivision of H. Such classes of graphs are related to many known graph classes: for example, K2-graphs correspond to interval graphs, K3-graphs correspond to circular-arc graphs, the union of T-graphs, where T ranges over all trees, correspond to chordal graphs. Recently, quite a lot of research has been devoted to understanding the tractability border for various computational problems, such as recognition or isomorphism testing, in classes of H-graphs for different graphs H. In this work we undertake this research topic, focusing on the recognition problem. Chaplick, Töpfer, Voborník, and Zeman showed an XP-algorithm testing whether a given graph is a T-graph, where the parameter is the size of the tree T. In particular, for every fixed tree T the recognition of T-graphs can be solved in polynomial time. Tucker showed a polynomial time algorithm recognizing K3-graphs (circular-arc graphs). On the other hand, Chaplick at al. showed also that recognition of H-graphs is NP-hard if H contains two different cycles sharing an edge. The main two results of this work narrow the gap between the NP-hard and P cases of H-graphs recognition. First, we show that recognition of H-graphs is NP-hard when H contains two different cycles. On the other hand, we show a polynomial-time algorithm recognizing L-graphs, where L is a graph containing a cycle and an edge attached to it (L is called a lollipop and L-graphs are called lollipop graphs). Clearly, the class of lollipop graphs extends the class of circular-arc graphs. Our work leaves open the recognition problems of M-graphs for every unicyclic graph M different from a cycle and a lollipop. Other results of this work, which shed some light on the cases that remain open, are as follows: • recognition of M-graphs, where M is a fixed unicyclic graph, admits a polynom

关键词： Polynomial approximation

Two-Dimensional Phase-Fluctuating Superconductivity in Bulk-Crystalline NdO0.5F0.5BiS2

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arXiv 2024年

作者： Chen, C.S. Küspert, J. Bialo, I. Mueller, J. Chen, K.W. Zou, M.Y. Mazzone, D.G. Bucher, D. Tanaka, K. Ivashko, O. Zimmermann, M.V. Wang, Qisi Shu, Lei Chang, J. State Key Laboratory of Surface Physics Department of Physics Fudan University Shanghai200433 China Physik-Institut Universität Zürich Winterthurerstrasse 190 ZürichCH-8057 Switzerland AGH University of Krakow Faculty of Physics and Applied Computer Science Krakow30-059 Poland Laboratory for Neutron Scattering and Imaging Paul Scherrer Institut Villigen PSICH-5232 Switzerland Department of Physics and Engineering Physics University of Saskatchewan 116 Science Place SaskatoonSKS7N 5E2 Canada Deutsches Elektronen-Synchrotron DESY Notkestraße 85 Hamburg22607 Germany Department of Physics The Chinese University of Hong Kong Shatin Hong Kong

We present a combined growth and transport study of superconducting single-crystalline NdO0.5F0.5BiS2. Evidence of two-dimensional superconductivity with significant phase fluctuations of preformed Cooper pairs preceding the superconducting transition is reported. This result is based on three key observations. (1) The resistive superconducting transition temperature Tc (defined by resistivity ρ → 0) increases with increasing disorder. (2) As T → Tc, the conductivity diverges significantly faster than what is expected from Gaussian fluctuations in two and three dimensions. (3) Non-Ohmic resistance behavior is observed in the superconducting state. Altogether, our observations are consistent with a temperature regime of phase-fluctuating superconductivity. The crystal structure with magnetic ordering tendencies in the NdO0.5F0.5 layers and (super)conductivity in the BiS2 layers is likely responsible for the two-dimensional phase fluctuations. As such, NdO0.5F0.5BiS2 falls into the class of unconventional "laminar" bulk superconductors that include cuprate materials and 4Hb-TaS2 Copyright © 2024, The Authors. All rights reserved.

关键词： Bismuth compounds

Image Reconstruction with B0 Inhomogeneity using an Interpretable Deep Unrolled Network on an Open-bore MRI-Linac

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arXiv 2024年

作者： Shan, Shanshan Gao, Yang Waddington, David E.J. Chen, Hongli Whelan, Brendan Liu, Paul Z.Y. Wang, Yaohui Liu, Chunyi Gan, Hongping Gao, Mingyuan Liu, Feng Soochow University Suzhou215123 China Image X Institute Sydney School of Health Sciences Faculty of Medicine and Health University of Sydney Sydney2015 Australia Department of Medical Physics Ingham Institute of Applied Medical Research Liverpool2170 Australia School of Computer Science and Engineering Central South University Changsha410083 China School of Electrical Engineering and Computer Science University of Queensland Brisbane4072 Australia Institute of Electrical Engineering Chinese Academy of Science Beijing100190 China School of Software Northwestern Polytechnical University Taicang215400 China

MRI-Linac systems require fast image reconstruction with high geometric fidelity to localize and track tumours for radiotherapy treatments. However, B0 field inhomogeneity distortions and slow MR acquisition potentially limit the quality of the image guidance and tumour treatments. In this study, we develop an interpretable unrolled network, referred to as RebinNet, to reconstruct distortion-free images from B0 inhomogeneity-corrupted k-space for fast MRI-guided radiotherapy applications. RebinNet includes convolutional neural network (CNN) blocks to perform image regularizations and nonuniform fast Fourier Transform (NUFFT) modules to incorporate B0 inhomogeneity information. The RebinNet was trained on a publicly available MR dataset from eleven healthy volunteers for both fully sampled and subsampled acquisitions. Grid phantom and human brain images acquired from an open-bore 1T MRI-Linac scanner were used to evaluate the performance of the proposed network. The RebinNet was compared with the conventional regularization algorithm and our recently developed UnUNet method in terms of root mean squared error (RMSE), structural similarity (SSIM), residual distortions, and computation time. Imaging results demonstrated that the RebinNet reconstructed images with lowest RMSE (0.92) at four-time acceleration for simulated brain images. The RebinNet could better preserve structural details and substantially improve the computational efficiency (ten-fold faster) compared to the conventional regularization methods, and had better generalization ability than the UnUNet method. The proposed RebinNet can achieve rapid image reconstruction and overcome the B0 inhomogeneity distortions simultaneously, which would facilitate accurate and fast image guidance in radiotherapy treatments. © 2024, CC BY-NC-ND.

关键词： Magnetic resonance imaging

Covering factor in AGNs: evolution versus selection

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arXiv 2023年

作者： Ralowski, Mateusz Hryniewicz, Krzysztof Pollo, Agnieszka Stawarz, Lukasz Astronomical Observatory of the Jagiellonian University Faculty of Physics Astronomy and Applied Computer Science ul. Orla 171 Cracow30-244 Poland National Centre for Nuclear Research ul. Pasteura 7 Warsaw02-093 Poland Jagiellonian University Doctoral School of Exact and Natural Sciences Astronomy Poland

Aims. In every proposed unification scheme for Active Galactic Nuclei (AGN), an integral element is the presence of circumnuclear dust arranged in torus-like structures, partially obscuring the nuclear (accretion-associated) radiation. A crucial model parameter in this context is the covering factor (CF), which can be defined as the ratio between the infrared luminosity of the dusty torus, LIR, and the accretion disk bolometric luminosity, Lagn. Recent research has discussed the potential redshift evolution of the CF. Our study aims to determine whether this observed evolution is genuine or if selection effects significantly influence it. Methods. Based on cross-matched multiwavelength photometrical data from the five major surveys (SDSS, GALEX, UKIDSS, WISE, SPITZER), a sample of over 17,000 quasars was derived. The main parameters of quasars, such as black hole masses and the Eddington ratios, were calculated based on the spectroscopic data. The data were divided into two redshift bins: Low-z (redshift from 0.7 to 1.1) and High-z (from 2.0 to 2.4) quasars. The associated smaller data sets with higher quality data were constructed from a) the WISE W3&W4 detections with SNR > 5, and b) the SPITZER MIPS 24 µm photometry. The CF was determined by computing the ratio of integrated luminosities, LIR and Lagn, using two methods: 1) power-law fitting, and 2) the area between all photometric points. We explored different selection effects and their influence on CF estimates. Finally, statistical tests were employed to assess the hypothesis of CF evolution within the higher-quality datasets. Results. We identified an issue with the accuracy of the WISE W4 filter. Whenever feasible, it is recommended to utilize SPITZER MIPS 24 µm data. Luminosities obtained through direct integration of all photometric data points exhibit higher accuracy compared to values derived from a power-law approximation. The Efron & Petrosian test confirmed the presence of luminosity evolution with r

关键词： Luminance

Grain Stresses and Critical Resolved Shear Stresses in Duplex Steel Studied Using Neutron Diffraction and Crystallite Group Method

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SSRN

SSRN 2024年

作者： Baczmański, Andrzej Wroński, Sebastian François, Manuel Le Joncour, Léa Panicaud, Benoit Braham, Chedly Ludwik, Aleksandra Wierzbanowski, Krzysztof Klosek, Vincent AGH University of Kraków Faculty of Physics and Applied Computer Science al. Mickiewicza 30 Kraków30-059 Poland 12 rue Marie Curie Troyes10010 France PIMM 151 Bd de l’Hôpital 75013 Paris France CEA IRAMIS Laboratoire Léon Brillouin Gif-sur-Yvette91191 Cedex France

In this work, a new method for analysis of neutron diffraction results obtained during in situ tensile load is tested and applied to study elastic-plastic properties of textured duplex steel. The methodology is based on the measurements of lattice strains for several hkl reflections and for different orientations of the sample with respect to the scattering vector. As the result, the full stress tensor for preferred texture orientations in function of applied stress has been determined using the crystallite group method (CGM). Knowing the experimental values of stresses, the stress concentration tensor is determined. The experimental data are then compared with self-consistent model calculations performed for groups of grains corresponding to the measured hkl reflections. The important advance of the proposed experimental methodology consists in the possibility of estimating the critical resolved shear stresses (CRSSs) directly from measurements, without the use of any elastic-plastic *** the research carried out, on the basis of diffraction measurements, the evolution of grain stresses in preferred orientations in the ferritic and austenitic phases of the tested duplex steel was determined. Using these data, the evolution of the resolved shear stress (RSS) was analysed and, for the first time, CRSS values in both duplex phases were obtained directly from the experimental data. The final results also took into account the influence of initial stresses in the obtained material on the determined CRSSs. © 2024, The Authors. All rights reserved.

关键词： Neutron diffraction

Influence of Structural Defects on Charge Density Waves in 1T-TaS2

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arXiv 2023年

作者： Lutsyk, I. Szalowski, K. Krukowski, P. Dabrowski, P. Rogala, M. Kozlowski, W. Le Ster, M. Piskorski, M. Kowalczyk, D.A. Rys, W. Dunal, R. Nadolska, A. Toczek, K. Przybysz, P. Lacinska, E. Binder, J. Wysmolek, A. Olszowska, N. Kolodziej, J.J. Gmitra, M. Hattori, T. Kuwahara, Y. Bian, G. Chiang, T.-C. Kowalczyk, P.J. Faculty of Physics and Applied Informatics University of Lodz Pomorska 149/153 Lodz90-236 Poland Faculty of Physics University of Warsaw Pasteura 5 Warsaw02-093 Poland Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University Lojasiewicza 11 Krakow30-348 Poland National Synchrotron Radiation Centre SOLARIS Jagiellonian University Czerwone Maki 98 Kraków30-392 Poland Institute of Physics Faculty of Science Pavol Jozef Šafárik University in Košice Park Angelinum 9 Košice040 01 Slovakia Institute of Experimental Physics Slovak Academy of Sciences Watsonova 47 Košice040 01 Slovakia Department of Precision Engineering Graduate School of Engineering Osaka University 2-1 Yamada-oka Suita565-0871 Japan Department of Physics and Astronomy University of Missouri ColumbiaMO65211 United States Department of Physics Frederick Seitz Materials Research Laboratory University of Illinois at Urbana-Champaign UrbanaIL61801-3080 United States

The influence of intrinsic defects of 1T-TaS2 on charge density waves (CDW) is studied using scanning tunneling microscopy and spectroscopy (STM, STS), angle-resolved photoelectron spectroscopy (ARPES), and density functional theory (DFT). We identify several types of structural defects and find that most have a local character limited to the single CDW site, with single exception which effectively behaves as a dopant, leading to band bending and affecting multiple neighboring sites. While only one type of defect can be observed by STM topographic imaging, all defects are easily resolved by local density of states (LDOS) mapping with STS. We correlate atomically-resolved STM periodicity of defect-free 1T-TaS2 to top sulfur atoms and introduce tiling of the surface using equiangular hexagon. DFT calculations (with included Coulomb interactions) are used to investigate the electronic structure by introducing sulfur vacancy or substituting sulfur with oxygen. The sulfur vacancy is characterized by metallic properties and is identified as an origin of one of observed experimentally defects. Whereas in the case of the latter, the oxidation of 1T-TaS2 is found to result in the loss of magnetic properties expected in defect-free material. © 2023, CC0.

关键词： Charge density waves

A New IoT-Based Smart Greenhouse for Cultivation of Water Convolvulus

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A New IoT-Based Smart Greenhouse for Cultivation of Water Co...

13th International Electrical Engineering Congress, iEECON 2025

作者： Akkaraekthalin, Prayoot Somwong, Tanee Chudpooti, Nonchanutt Hirun, Nuttawut Meesomklin, Suwaluck King Mongkut's University of Technology North Bangkok Faculty of Engineering Department of Electrical and Computer Engineering Bangkok10800 Thailand Rajamangala University of Technology Suvarnabhumi Faculty of Engineering and Architecture Department of Electronic and Telecommunications Engineering Nonthaburi11000 Thailand King Mongkut's University of Technology North Bangkok Faculty of Applied Science Department of Industrial Physics and Medical Instrumentation Bangkok10800 Thailand King Mongkut's University of Technology North Bangkok College of Industrial Technology Department of Electronics Engineering Technology Bangkok10800 Thailand

ISBN: (纸本)9798331543952

This paper presents a new IOT system for monitoring and controlling plant cultivation in greenhouse system. The system aims to regulate and monitor the environmental conditions suitable for plant cultivation in real-time. The system utilizes sensors to measure environmental conditions, such as soil moisture sensor, light intensity sensor, temperature sensor, and air humidity sensor. The Node MCU ESP32 is used for processing and controlling these operations. The system is designed to send notifications through Line application and allows farmers to monitor the system's performance and plant growth in real-time via a smartphone application. It can utilize the Blynk IoT application on a smartphone for remotely monitoring and controlling the environmental conditions and provides historical data. This experiment demonstrates that the designed system can successfully cultivate plants and promote better growth compared to traditional cultivation methods with a 13.38% improvement. Additionally, it provides convenience and ease of management for plant cultivation. © 2025 IEEE.

关键词： greenhouse system IOT smart agriculture Smart farming water convolvulus

NO FORMATION OF A NEW PHASE FOR A FREE BOUNDARY PROBLEM IN COMBUSTION THEORY

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arXiv 2024年

作者： Furukawa, Ken Giga, Yoshikazu Kajiwara, Naoto Faculty of Science Academic Assembly University of Toyama 3190 Gofuku Toyama-shi Toyama930-8555 Japan Graduate School of Mathematical Sciences The University of Tokyo 3-8-1 Komaba Meguro-ku Tokyo153-8914 Japan Applied Physics Course Department of Electrical Electronic and Computer Engineering Gifu University 1-1 Yanagido Gifu501-1193 Japan

We consider a free boundary problem for the heat equation with a given non-negative external heat source. On the free boundary, we impose the zero Dirichlet condition and the fixed normal derivative so that heat escapes from the boundary. In various settings, we show that there exist no solutions when the initial temperature equals the fixed temperature no matter where the initial location of the free boundary is given provided that the external heat source is bounded from above. We also note that there is a chance to have a solution when the external temperature is unbounded as time tends to zero by giving a self-similar solution. Copyright © 2024, The Authors. All rights reserved.

关键词： Laplace transforms