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2021 European Physical Society Conference on High Energy physics, EPS-HEP 2021

作者： del Río, Elena Pérez Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University S. Lojasiewicza 11 Kraków30-348 Poland

The Positronium (Ps) system, a bound state of an electron and a positron, is suitable for testing the predictions of quantum electrodynamics (QED), since its properties can be perturbatively calculated to high accuracy and, unlike the hydrogen system, is not affected by finite size or QCD effects at the current experimental precision level. This makes the Ps atom a good laboratory to test the Fundamental Symmetries of physics and also search for new particles not included in the Standard Model (SM) of physics. On one hand, time reversal (T) and CP symmetry violation have never been observed in pure leptonic systems like the Ps atom, and the current experimental limits for CP and CPT violation in the decays of Ps is currently set at the level of 10−3, while for C violation are at the level of 10−7. These limits are still six and two orders of magnitude lower than the expected precision of 10−9 set by photon-photon interactions. Secondly, experiments searching for invisible decays of the Ps triplet state, the ortho-Positronium (o-Ps), which mainly decays to three photons, are being conducted, since they are sensitive to new physics scenarios, e.g. Mirror Matter (MM), a suitable Dark Matter candidate, proposed to restore parity (P) violation. By performing a high precision measurement of the o-Ps lifetime, the accuracy of the present QED calculations can be tested and a search for the invisible decays of the o-Ps can be performed. These studies are conducted with the novel total-body Positron-Electron Tomograph (PET) scanner at the Jagiellonian University. The J-PET is a large and high precise medical imaging tool, based on the plastic scintillators. It is a high acceptance multi-purpose detector optimized for the detection of photons from positron-electron annihilation and can be used in a broad scope of interdisciplinary investigation, e.g. medical imaging, life-time measurements, quantum entanglement studies with o-Ps, and tests of discrete symmetries. © Copyright o

关键词： Positrons

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The liberation set in the inverse eigenvalue problem of a graph

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arXiv 2023年第1期675卷 1-28页

作者： Lin, Jephian C.-H. Oblak, Polona Šmigoc, Helena Department of Applied Mathematics National Sun Yat-sen University Kaohsiung80424 Taiwan Faculty of Computer and Information Science University of Ljubljana Večna pot 113 LjubljanaSI-1000 Slovenia Faculty of Mathematics and Physics University of Ljubljana Institute of Mathematics Physics and Mechanics Jadranska ulica 19 Ljubljana1000 Slovenia School of Mathematics and Statistics University College Dublin BelfieldDublin 4 Ireland

The inverse eigenvalue problem of a graph G is the problem of characterizing all lists of eigenvalues of real symmetric matrices whose off-diagonal pattern is prescribed by the adjacencies of G. The strong spectral property is a powerful tool in this problem, which identifies matrices whose entries can be perturbed while controlling the pattern and preserving the eigenvalues. The Matrix Liberation Lemma introduced by Barrett et al. in 2020 advances the notion to a more general setting. In this paper we revisit the Matrix Liberation Lemma and prove an equivalent statement, that reduces some of the technical difficulties in applying the result. We test our method on matrices of the form M = AB and show how this new approach supplements the results that can be obtained from the strong spectral property only. While extending this notion to the direct sums of graphs, we discover a surprising connection with the zero forcing game on Cartesian products of graphs. Throughout the paper we apply our results to resolve a selection of open cases for the inverse eigenvalue problem of a graph on six *** Codes 05C50, 15A18, 15B57, 65F18 © 2023, CC BY-SA.

关键词： Matrix algebra

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Wilson line-based action for gluodynamics at the loop level

arXiv

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arXiv 2024年

作者： Kakkad, Hiren Kotko, Piotr Stasto, Anna AGH University Faculty of Physics and Applied Computer Science al. Mickiewicza 30 Krakow30-059 Poland The Pennsylvania State University Physics Department 104 Davey Lab University ParkPA16802 United States

We develop quantum corrections to the Wilson line-based action which we recently derived through a transformation that eliminates triple gluon vertices from the Yang-Mills action on the light-cone. The action efficiently computes high multiplicity tree-level split-helicity amplitudes with the number of diagrams following the Delannoy number series. However, the absence of the triple gluon vertices results in missing loop contributions. To remedy this, we develop two equivalent approaches using the one-loop effective action method to systematically incorporate loop contributions to our action. In one approach there are solely Yang-Mills vertices in the loop whereas the other uses the interaction vertices of our action along with the kernels of the solution of our transformation in the loop. In addition to demonstrating the equivalence of both approaches, we validated the quantum completeness of the former by computing all 4-point one-loop amplitudes which could not be previously computed. Both of our approaches are easily extendable to develop quantum corrections to other reformulations of the Yang-Mills theory obtained via non-linear classical field transformations eliminating interaction vertices. Copyright © 2024, The Authors. All rights reserved.

关键词： Linear transformations

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Simple method of failure detection of rotary machines

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Diagnostyka 2021年第4期22卷 17-22页

作者： Bielecki, Andrzej Bielecka, Marzena Jablonski, Adam Staszewski, Wojciech Institute of Computer Science Faculty of Exact and Natural Sciences Pedagogical University in Krakow Podchorazych 2 Krakow30-084 Poland Geoinformatics and Applied Computer Science Faculty of Geology Geophysics and Environmental Protection AGH University of Science and Technology Mickiewicza 30 Krakow30-059 Poland Robotics and Mechatronics Faculty of Mechanical Engineering and Robotics AGH University of Science and Technology Mickiewicza 30 Krakow30-059 Poland

In the paper a simple unsupervised monitoring method of rotary machines is proposed. The method consists of three stages multi-reference preliminary analysis of the vibration signals, auto-reference preliminary analysis and probabilistic analysis of the signals. The method was tested by using signals from eight simulated machines. The efficiency of the method has been positively verified. © 2021 Polish Society of Technical Diagnostics. All rights reserved.

关键词： Vibration analysis

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Optimization of Cognitive Radio System Using Enhanced Firefly Algorithm

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Intelligent Automation & Soft Computing 2023年第9期37卷 3159-3177页

作者： Nitin Mittal Rohit Salgotra Abhishek Sharma Sandeep Kaur SSAskar Mohamed Abouhawwash University Center for Research and Development Chandigarh UniversityMohaliPunjab140413India Faculty of Physics and Applied Computer Science AGH University of Science&TechnologyKrakowPoland Faculty of Information Technology Middle East UniversityAmman11813Jordan Department of Computer Engineering and Applications GLA UniversityMathura281406India Department of Computer Engineering&Technology Guru Nanak Dev UniversityAmritsarPunjab143005India Department of Statistics and Operations Research College of ScienceKing Saud UniversityP.O.Box 2455Riyadh11451Saudi Arabia Department of Computational Mathematics Science and EngineeringCollege of EngineeringMichigan State UniversityEast LansingMI48824USA Department of Mathematics Faculty of ScienceMansoura UniversityMansoura35516Egypt

The optimization of cognitive radio(CR)system using an enhanced firefly algorithm(EFA)is presented in this *** Firefly algorithm(FA)is a nature-inspired algorithm based on the unique light-flashing behavior of *** has already proved its competence in various optimization prob-lems,but it suffers from slow convergence *** improve the convergence performance of FA,a new variant named EFA is *** effectiveness of EFA as a good optimizer is demonstrated by optimizing benchmark functions,and simulation results show its superior performance compared to biogeography-based optimization(BBO),bat algorithm,artificial bee colony,and *** an application of this algorithm to real-world problems,EFA is also applied to optimize the CR *** is a revolutionary technique that uses a dynamic spectrum allocation strategy to solve the spectrum scarcity ***,it requires optimization to meet specific performance *** results obtained by EFA in CR system optimization are compared with results in the literature of BBO,simulated annealing,and genetic *** results further prove that the proposed algorithm is highly efficient and provides superior results.

关键词： Firefly algorithm cognitive radio bit error rate genetic algorithm simulated annealing biogeography-based optimization

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Rényi entropy of zeta urns

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Physical Review E 2023年第6期108卷 064108-064108页

作者： Piotr Bialas Zdzislaw Burda Desmond A. Johnston Institute of Applied Computer Science Jagiellonian University Ulica Lojasiewicza 11 30-348 Kraków Poland Faculty of Physics and Applied Computer Science AGH University of Krakow Aleja Mickiewicza 30 30-059 Kraków Poland School of Mathematical and Computer Sciences Heriot-Watt University Riccarton Edinburgh EH14 4AS United Kingdom

We calculate analytically the Rényi entropy for the zeta-urn model with a Gibbs measure definition of the microstate probabilities. This allows us to obtain the singularities in the Rényi entropy from those of the thermodynamic potential, which is directly related to the free-energy density of the model. We enumerate the various possible behaviors of the Rényi entropy and its singularities, which depend on both the value of the power law in the zeta urn and the order of the Rényi entropy under consideration.

关键词： Critical phenomena Information thermodynamics Phase transitions Zero-range process

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Acoustic cavitation bubble under influence of frequency ultrasound: Numerical analysis 3

Acoustic cavitation bubble under influence of frequency ultr...

引用

3rd IEEE International Conference on Electronic Engineering, ICEEM 2023

作者： Abu-Nab, A.K. Abu-Bakr, A.F. Abushaeer, Zain Menoufia University Faculty of Science Department of Mathematics and Computer Science Shebin El-Koom32511 Egypt Moscow Institute of Physics and Technology Phystech School of Applied Mathematics and Informatics Moscow141700 Russia Menoufia University Faculty of Science Department of Mathematics and Computer Science Shebin El-Koom32511 Egypt Higher Institute of Engineering and Technology Department of Basic Science Kafrelsheikh33511 Egypt

ISBN: (纸本)9798350323511

This work presents a numerical investigation of acoustic cavitation in Newtonian fluid based on frequency ultrasound. The model of ultrasonic cavitation dynamics is formulated by a modified Rayleigh-Plesset equation and an acoustic pressure equation. The exponential B-Spline collection method was employed to obtain the numerical solutions of the given cavitation bubble model, considering the effect of acoustic pressure. The behaviour of the cavitation microbubbles' radius and the internal pressure of acoustic cavitation were examined at different values of frequencies. The obtained results reveal the importance of frequencies in ultrasound, which play a vital role in changing the behaviour of cavitation bubbles. © 2023 IEEE.

关键词： Numerical methods

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Random allocation models in the thermodynamic limit

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Physical Review E 2023年第6期108卷 064107-064107页

We discuss the phase transition and critical exponents in the random allocation model (urn model) for different statistical ensembles. We provide a unified presentation of the statistical properties of the model in the thermodynamic limit, uncover relationships between the thermodynamic potentials, and fill some lacunae in previous results on the singularities of these potentials at the critical point and behavior in the thermodynamic limit. The presentation is intended to be self-contained, so we carefully derive all formulas step by step throughout. Additionally, we comment on a quasiprobabilistic normalization of configuration weights, which was considered in some recent studies.

关键词： Classical statistical mechanics Phase diagrams Phase transitions Phase transitions by order Specific phase transitions Zero-range process

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Observation of two zeros of the real amplitude in pp scattering at LHC energies

arXiv

引用

arXiv 2022年

作者： Kohara, Anderson Kendi AGH University Of Science and Technology Faculty of Physics and Applied Computer Science Mickiewicza 30 Kraków30-059 Poland

Elastic scattering of charged hadrons is described by the combination of nuclear and Coulomb amplitudes. It is well know that at the very forward range the nuclear real and Coulomb parts interplay a crucial role in the determination of the magnitude of the real part at |t| = 0. However, beyond |t| = 0 the real and imaginary nuclear amplitudes have different t dependencies and we show that at LHC energies the zeros formed by the combination TC(t)+TRN(s,t) = 0 in pp process can be potentially observed when the background due to the imaginary part is removed. This observation constrains the real part at this forward range. Copyright © 2022, The Authors. All rights reserved.

关键词： Elastic scattering

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Electronic structure of CeIr3 superconductor: DMFT studies

arXiv

引用

arXiv 2022年

作者： Gutowska, Sylwia Wiendlocha, Bartlomiej Faculty of Physics and Applied Computer Science AGH University of Science and Technology Aleja Mickiewicza 30 Krakow30-059 Poland

We present the band structure of CeIr3 superconductor calculated within the dynamical mean field theory (DMFT). Standard GGA and GGA+U methods fail to reproduce the experimental electronic specific heat coefficient γexpt. due to the underestimated density of states at the Fermi level N(EF) followed by an overestimated strength of electron-phonon coupling (EPC) calculated as a renormalization of γexpt.. The DMFT study shows a strong hybridization of 4f states of Ce with 5d-states of Ir, which leads to the larger N(EF) giving the correct γexpt. with a moderate EPC in agreement with the experimental data. Copyright © 2022, The Authors. All rights reserved.

关键词： Electronic structure

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