Journal of the Korean Physical Society最新文献_第8页

Identification of tqg flavor-changing neutral current interactions using machine learning techniques 使用机器学习技术识别tqg改变风味的中性电流相互作用

IF 0.8 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2025-01-06 DOI: 10.1007/s40042-024-01277-3

Byeonghak Ko, Jeewon Heo, Woojin Jang, Jason Sang Hun Lee, Youn Jung Roh, Ian James Watson, Seungjin Yang

{"title":"Identification of tqg flavor-changing neutral current interactions using machine learning techniques","authors":"Byeonghak Ko, Jeewon Heo, Woojin Jang, Jason Sang Hun Lee, Youn Jung Roh, Ian James Watson, Seungjin Yang","doi":"10.1007/s40042-024-01277-3","DOIUrl":"10.1007/s40042-024-01277-3","url":null,"abstract":"<div>Flavor-changing neutral currents (FCNCs) are forbidden at tree level in the standard model (SM), but they can be enhanced in physics beyond the standard model (BSM) scenarios. In this paper, we investigate the effectiveness of deep learning techniques to enhance the sensitivity of current and future collider experiments to the production of a top quark and an associated parton through the tqg FCNC process, which originates from the tug and tcg vertices. The tqg FCNC events can be produced with a top quark and either an associated gluon or quark, while SM only has events with a top quark and an associated quark. We apply machine learning techniques to distinguish the tqg FCNC events from the SM backgrounds, including qg-discrimination variables. We use the Boosted Decision Tree (BDT) method as a baseline classifier, assuming that the leading jet originates from the associated parton. We compare with a transformer-based deep learning method known as the Self-Attention for Jet-parton Assignment (SaJa) network, which allows us to include information from all jets in the event, regardless of their number, eliminating the necessity to match the associated parton to the leading jet. The SaJa network with qg-discrimination variables has the best performance, giving expected upper limits on the branching ratios ({Br}(t rightarrow qg)) that are 25–35% lower than those from the BDT method.</div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"86 4","pages":"269 - 279"},"PeriodicalIF":0.8,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143388776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ciliary-based propulsion of Paramecium aurelia under varying viscosity 不同黏度条件下草履虫的纤毛推进

IF 0.8 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2025-01-03 DOI: 10.1007/s40042-024-01275-5

Caden Kesselring, Paul Peragino, Anthony Espanol, Andrew McGovern, Ilyong Jung

{"title":"Ciliary-based propulsion of Paramecium aurelia under varying viscosity","authors":"Caden Kesselring, Paul Peragino, Anthony Espanol, Andrew McGovern, Ilyong Jung","doi":"10.1007/s40042-024-01275-5","DOIUrl":"10.1007/s40042-024-01275-5","url":null,"abstract":"<div>Paramecia swim along helical trajectories propelled by the coordinated beating of the thousands of cilia covering their bodies. We have investigated how the swimming of populations of paramecium aurelia changes their swimming trajectories with varying viscosity, η, of their swimming medium to obtain their motor characteristics. The swimming speed distributions for 1 cP < η < 5.2 cP are Gaussian. The average instantaneous speed, v, and the variance, Δv, decrease monotonically with η. Simultaneously, their helical trajectories monotonically develop a greater pitch and radius. The product ηv is roughly constant over this factor of 5 change in η, indicating that paramecia aurelia swim with a constant propulsive force. Here, we present a phenomenological model of the beating cilia that produces the helical trajectory with a minimum number of swimming parameters. The model implies that the beat frequency of the body cilia decreases with increasing viscosity. The decrease can account for most of the observed decrease in swimming speed with η. We also find that the frequency of the cilia beating in the oral groove, which draws nutrients in, changes little with viscosity in sharp contrast with the body cilia responsible for propulsion.</div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"86 4","pages":"324 - 330"},"PeriodicalIF":0.8,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143388711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A study of the (α, p) reaction on 40Ca, 44Ca, and 48Ca 40Ca, 44Ca， 48Ca上（α, p）反应的研究

IF 0.8 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2024-12-26 DOI: 10.1007/s40042-024-01264-8

A. Somadder, R. Das, A. A. Sumon, U. K. Mazumder, S. K. Das

{"title":"A study of the (α, p) reaction on 40Ca, 44Ca, and 48Ca","authors":"A. Somadder, R. Das, A. A. Sumon, U. K. Mazumder, S. K. Das","doi":"10.1007/s40042-024-01264-8","DOIUrl":"10.1007/s40042-024-01264-8","url":null,"abstract":"<div>The three-nucleon transfer (α, p) reaction has been analyzed within the framework of the full finite-range (FFR) distorted-wave Born approximation (DWBA) method at an incident energy of 31 MeV. To investigate the bound states of the 43Sc, 47Sc, and 51Sc nuclei for 8, 4, and 5 transitions, respectively, the four forms of the optical model potentials, such as Woods–Saxon, Michel, shallow non-monotonic (molecular), and deep non-monotonic (DNM) potentials are used. The three-nucleon transfer spectroscopic factors have been extracted for the observed angular distributions of the 40Ca(( alpha ), p)43Sc, 44Ca((alpha ), p)47Sc, and 48Ca((alpha ), p)51Sc reactions for all forms of the optical model potentials. The spectroscopic factors that have been obtained in different states of the 43Sc, 47Sc, and 51Sc nuclei are mostly consistent for all forms of the potentials. The (chi_{N}^{2}) values are computed for the α+ 40, 44, 48Ca elastic scattering and the (α, p) reactions with targets 40Ca, 44Ca, and 48Ca to evaluate the quality of the fits. The two forms of the non-monotonic potentials, namely the molecular and DNM potentials, give an overall satisfactory description of the elastic scattering and reaction data than the Woods–Saxon and Michel potentials. Moreover, in this study, the form factors of the (α, p) reaction on 40Ca have also been calculated for L = 1, 3, and 5 transfers.</div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"86 3","pages":"159 - 172"},"PeriodicalIF":0.8,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Quality improvement of SiC single crystal by modification of hot zone design adoption with denser graphite insulation in PVT growth 在PVT生长过程中，采用更致密的石墨绝缘来改进热区设计以提高SiC单晶的质量

IF 0.8 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2024-12-26 DOI: 10.1007/s40042-024-01273-7

Seung Jun Lee, Su Ho Kim, Chae Young Lee, Jong Hwi Park, Jung Woo Choi, Jung Gyu Kim, Kap Ryeol Ku, Jung Gon Kim, Won Jae Lee

{"title":"Quality improvement of SiC single crystal by modification of hot zone design adoption with denser graphite insulation in PVT growth","authors":"Seung Jun Lee, Su Ho Kim, Chae Young Lee, Jong Hwi Park, Jung Woo Choi, Jung Gyu Kim, Kap Ryeol Ku, Jung Gon Kim, Won Jae Lee","doi":"10.1007/s40042-024-01273-7","DOIUrl":"10.1007/s40042-024-01273-7","url":null,"abstract":"<div>The density of graphite insulation largely affects a temperature gradient of the horizontal direction of the hot-zone in SiC crystal growth using the physical vapor transport (PVT) method. Three types of stacking configurations of graphite insulation with different densities were implemented to graphite hot-zone. The stacking configuration adoption with denser graphite insulation at the seed region gives rise positive effect on the achievement of a convex crystal shape, no polytype inclusion, improvement of crystal quality as well as lower defect density due to maintainance of constant temperature gradient during the SiC crystal growth. These results were investigated using ultraviolet fluorescence (UVF) images, map of Full width at half maximum (FWHM) and shift of an X-ray rocking curve (Omega scan), and surface morphology analysis after molten KOH etching. Optimization of hot-zone design adopting with stacking configuration of graphite insulation led to high-quality SiC crystal through the PVT method.</div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"86 3","pages":"223 - 228"},"PeriodicalIF":0.8,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analytical modelling and performance study of single-junction GaAs-based solar cell efficiency 单结砷化镓太阳能电池效率分析建模与性能研究

IF 0.8 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2024-12-24 DOI: 10.1007/s40042-024-01260-y

Athil S. Ibrahim Al-Ezzi, M. N. M. Ansari

{"title":"Analytical modelling and performance study of single-junction GaAs-based solar cell efficiency","authors":"Athil S. Ibrahim Al-Ezzi, M. N. M. Ansari","doi":"10.1007/s40042-024-01260-y","DOIUrl":"10.1007/s40042-024-01260-y","url":null,"abstract":"<div>The main objective of this study is to fabricate a control (a standard single-junction solar cell grown straight on bare GaAs substrate) and flexible freestanding GaAs-based single-junction solar cells (grown on a graphene layer deposited on GaAs substrate). Besides, the research work aims to characterise and mathematically simulate the PV cell behaviour using COMSOL Multiphysics (version 6). The control PV cell, as a baseline for comparison, was epitaxially grown by metal–organic chemical vapour deposition (MOCVD). Whilst remote epitaxy technique in addition to the ‘MOCVD’ method was used to fabricate the flexible freestanding GaAs solar cells. Remote epitaxy technique was employed to reduce the cost of the expensive monocrystalline GaAs substrate and produce flexible solar cells. The electrical properties of the membranes, including the current–voltage (I–V) curve, dark current, and quantum efficiency, were measured experimentally to evaluate how new flexible membranes perform relative to the control (traditional PV cell). The results showed that the power conversion efficiency of the fabricated single-junction GaAs membranes was about 9% at air mass condition AM1.5 (1000 W/m2 insolation and 25 °C). Therefore, a mathematical simulation by COMSOL and a design of experiment by Minitab were proposed to improve their efficiency. The efficiency of the fabricated GaAs solar cells was enhanced to 19.62% by optimising the layer thickness and doping. Furthermore, the (I–V) curve, dark current, and quantum efficiency of the control solar cell as a benchmark for the flexible membrane were analysed by COMSOL Multiphysics/Semiconductor physics to compare with the experimental measurements.</div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"86 3","pages":"245 - 262"},"PeriodicalIF":0.8,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Magnetohydrodynamic stagnation flow of Al2O3–Cu–TiO2/H2O ternary nanofluid across a stretching/shrinking cylinder in the presence of nonlinear radiative heat and Arrhenius energy 在非线性辐射热和阿伦尼乌斯能存在下，Al2O3-Cu-TiO2 /H2O三元纳米流体在拉伸/收缩圆柱体中的磁流体力学滞止流动

IF 0.8 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2024-12-24 DOI: 10.1007/s40042-024-01271-9

Utpal Jyoti Das, Indushri Patgiri

{"title":"Magnetohydrodynamic stagnation flow of Al2O3–Cu–TiO2/H2O ternary nanofluid across a stretching/shrinking cylinder in the presence of nonlinear radiative heat and Arrhenius energy","authors":"Utpal Jyoti Das, Indushri Patgiri","doi":"10.1007/s40042-024-01271-9","DOIUrl":"10.1007/s40042-024-01271-9","url":null,"abstract":"<div>The stagnation flow in a ternary hybrid nanofluid towards a cylinder that stretches and shrinks with suction velocity is investigated in this work. Here, water serves as conventional fluid and the nanoparticles are titanium dioxide (TiO2), copper (Cu), and alumina (Al2O3). This work aims to study the flow behaviour for velocity, concentration, and temperature including the novel effects of heat radiation in energy equation and energy activation in concentration equation. Using proper similarity variables, governing equations are transformed to dimension-free form. The bvp4c method is used to solve these nonlinear dimension-free equations numerically. The flow behaviour of various physical parameters is studied graphically for velocity, temperature, and concentration boundary layer. Moreover, considerable importance in this investigation are skin friction coefficient, mass transport rate, and heat transport rate. Observation reveals that Reynolds number and suction parameter enhance fluid velocity and skin friction. Also, fluid velocity in the case of ternary hybrid nanofluid, i.e., for Al2O3–Cu–TiO2/H2O enhances than hybrid nanofluid (Al2O3–Cu/H2O) and nanofluid (Al2O3/H2O). The temperature profile and heat transport rate are improved by heat sources. Increasing the radiation parameter reduces fluid temperature by 4.76% from ternary to hybrid nanofluid and 4.54% from hybrid to nanofluid. Chemical reaction and Schmidt number reduce concentration boundary layer. This mathematical modelling of nanofluid with stretching/shrinking cylinder can benefit society through applications in some processes such as polymer sheets, crystal mass production, metal extrusion, bath cooling, and plate cooling.</div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"86 3","pages":"189 - 201"},"PeriodicalIF":0.8,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Erratum: Fe-doped buffer layer with graded layered AlGaN/GaN HEMT for millimeter-wave radar applications 校正：铁掺杂缓冲层与梯度层状AlGaN/GaN HEMT毫米波雷达应用

IF 0.8 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2024-12-24 DOI: 10.1007/s40042-024-01274-6

A. Akshaykranth, J. Ajayan, Sandip Bhattacharya

引用次数: 0

Oxidation behavior of Pt–Ru bimetallic thin films as gate electrodes by atomic layer deposition 原子层沉积Pt-Ru双金属薄膜作为栅电极的氧化行为

IF 0.8 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2024-12-23 DOI: 10.1007/s40042-024-01245-x

Young-Wan Kim, Hyun-Jae Woo, Hyunju Lee, Se-Hun Kwon, Woo-Jae Lee

{"title":"Oxidation behavior of Pt–Ru bimetallic thin films as gate electrodes by atomic layer deposition","authors":"Young-Wan Kim, Hyun-Jae Woo, Hyunju Lee, Se-Hun Kwon, Woo-Jae Lee","doi":"10.1007/s40042-024-01245-x","DOIUrl":"10.1007/s40042-024-01245-x","url":null,"abstract":"<div>Investigating the oxidation behavior of a bimetallic thin film for a durable gate electrode in complementary metal–oxide semiconductor (CMOS) devices is challenging. Herein, Pt–Ru bimetallic thin films were synthesized using atomic layer deposition (ALD), followed by intentional oxidation at 600 °C. The as-deposited Pt–Ru thin films presented distorted lattices due to the solid solution, whereas the X-ray diffraction (XRD) peaks of the oxidized Pt–Ru thin films did not shift, except for the Pt-rich oxidized Pt–Ru thin films. Interestingly, due to the high resistance of Pt to oxidation, Ru atoms in the Pt-rich oxidized Pt–Ru thin films were not oxidized under an oxidation atmosphere. Upon increasing the Ru content, Ru atoms started to oxidize, followed by full oxidization into Ru oxide in the Ru-rich Pt–Ru thin films. Simultaneously, Ru atoms moved to the surface and were oxidized with surface oxygen, thereby separating the upper Ru oxide and Pt metal layer. The resistivity of the oxidized Pt–Ru thin films increased as the Ru content increased, whereas the as-deposited Pt–Ru thin films exhibited a volcano-shaped peak depending on the relative composition between Ru and Pt. The work functions of the oxidized Pt–Ru thin films were higher than those of the as-deposited films, due to the higher work function of RuO2 than those of Ru metals; however, the Pt-dominant Pt–Ru thin films showed similar values both before and after oxidation, owing to the unoxidized Ru atoms.</div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"86 3","pages":"208 - 215"},"PeriodicalIF":0.8,"publicationDate":"2024-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thermoelectric properties of two-dimensional GaTe bilayer 二维栅极双分子层的热电性质

IF 0.8 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2024-12-20 DOI: 10.1007/s40042-024-01253-x

Jinmyeong Han, Jisang Hong

引用次数: 0

Erratum: On the observables of renormalizable interactions 勘误：关于可重整相互作用的可观察性

IF 0.8 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2024-12-20 DOI: 10.1007/s40042-024-01248-8

Kang-Sin Choi

引用次数: 0