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Impact Collision Operator for Unbounded Electrons in a Magnetized Plasma Model 磁化等离子体模型中无界电子的碰撞算子
Ukrainian Journal of Physics Pub Date : 2023-10-02 DOI: 10.15407/ujpe68.8.507
H. Guerrida, K. Chenini, M.T. Meftah, S. Douis, D.E. Zenkhri, K. Arif
{"title":"Impact Collision Operator for Unbounded Electrons in a Magnetized Plasma Model","authors":"H. Guerrida, K. Chenini, M.T. Meftah, S. Douis, D.E. Zenkhri, K. Arif","doi":"10.15407/ujpe68.8.507","DOIUrl":"https://doi.org/10.15407/ujpe68.8.507","url":null,"abstract":"The shapes of spectral lines in plasmas contain information about plasma parameters and can be used as a diagnostic tool. We have obtained a theoretical expression involving a Meijer function for the plasma collision operator for electrons in the presence of an external magnetic field. We have used the semiclassical theory and the impact approximation which concern the interaction between the emitting systems (hydrogen-like ions in this study) and the plasma electrons. We have calculated the collision operator amplitude for some hydrogen-like ions such as Ar+17, V+22, Cr+23, Fe+25, and Ag+46 for high density intervals between 1018 cm−3 to 1026 cm−3 and at high temperatures between 106 K to 1010 K in a very strong magnetic field between 100 T to 10,000 T. We have applied our results to the Lyman-alpha line, and the comparison with experimental data and some theoretical results gives a good agreement.","PeriodicalId":23400,"journal":{"name":"Ukrainian Journal of Physics","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135895842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Physical Aspects of 2014 Nobel Prize in Physiology or Medicine: 2. The First Principle and Universality Class for Grid Cells in the Brain 2014年诺贝尔生理学或医学奖的物理方面:大脑网格细胞的第一原理和普遍性
IF 0.5
Ukrainian Journal of Physics Pub Date : 2023-09-08 DOI: 10.15407/ujpe68.7.462
A.V. Chalyi, K. Chalyi, E.V. Zaitseva, E.N. Chaika, I.P. Kryvenko
{"title":"Physical Aspects of 2014 Nobel Prize in Physiology or Medicine: 2. The First Principle and Universality Class for Grid Cells in the Brain","authors":"A.V. Chalyi, K. Chalyi, E.V. Zaitseva, E.N. Chaika, I.P. Kryvenko","doi":"10.15407/ujpe68.7.462","DOIUrl":"https://doi.org/10.15407/ujpe68.7.462","url":null,"abstract":"The main purpose of this review article is to use the fluctuation theory of phase transitions for studying the process of the emergence of hexagonal grid cells in the brain (2014 Nobel Prize in Physiology or Medicine). Particular attention is paid to the application of the Feynman’s classification of three stages of the study of natural phenomena for: 1) a brief description of the experimental stage of the discovery of the hexagonal structures of grid cells in human and animal brains; 2) the theoretical stage of research on the hexagon formation in the physical system of Benard cells, as well as the neurophysiological system of grid cells, discovered by Edward Mozer and May-Britt Mozer; 3) the most important stage, which allows one to formulate the first principle of the emergence of grid cells in the brain and, generally speaking, the first principle for the hexagon formation in different objects of inanimate and living nature. Our original theoretical findings are the following: (a) Polyakov’s conformal invariance hypothesis is violated for a system of grid cells in the brain; (b) the system of grid cells in the brain belongs to the universality class including the 3D Ising model in a magnetic field, as well as a real classical liquid-vapor system;(c) to formulate the first principle for a reliable theoretical justification of the emergence of hexagonal grid cells in the brain, it is necessary to use the fluctuating part of Gibbs thermodynamic potential (the Ginzburg–Landau Hamiltonian) for a system with chemical (biochemical) reactions.","PeriodicalId":23400,"journal":{"name":"Ukrainian Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41345210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Магнетокалоричний ефект у спін-1/2 одновимірній XX моделі з двома регулярнозмінними g-факторами 具有两个正则g因子的1/2自旋一维模型XX中的磁氯效应
IF 0.5
Ukrainian Journal of Physics Pub Date : 2023-09-08 DOI: 10.15407/ujpe68.7.488
O. Baran
{"title":"Магнетокалоричний ефект у спін-1/2 одновимірній XX моделі з двома регулярнозмінними g-факторами","authors":"O. Baran","doi":"10.15407/ujpe68.7.488","DOIUrl":"https://doi.org/10.15407/ujpe68.7.488","url":null,"abstract":"Дослiджено вплив неоднорiдностi g-факторiв, коли вони є регулярнозмiнними з перiодом два, на магнетокалоричний ефект у спiн-1/2 XX ланцюжку в поперечному магнiтному полi. За допомогою перетворення Йордана–Вiґнера задача зводиться до гамiльтонiана невзаємодiючих безспiнових фермiонiв i розв’язується точно. Проаналiзовано, як змiнюються iзоентропи та польовi залежностi параметра Грюнайзена зi змiною g2/g1. Основна увага придiляється низько-температурнiй областi. Показано вiдмiнностi магнетокалоричного ефекту у випадках, коли g-фактори мають однаковi та рiзнi знаки, а також коли один iз g-факторiв дорiвнює нулю.","PeriodicalId":23400,"journal":{"name":"Ukrainian Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46478104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Effect of Sheared Magnetic Field on E × B Drift Instability in Plasma 剪切磁场对等离子体中E×B漂移不稳定性的影响
IF 0.5
Ukrainian Journal of Physics Pub Date : 2023-09-08 DOI: 10.15407/ujpe68.7.448
S. Nasrin, S. Das, M. Bose
{"title":"Effect of Sheared Magnetic Field on E × B Drift Instability in Plasma","authors":"S. Nasrin, S. Das, M. Bose","doi":"10.15407/ujpe68.7.448","DOIUrl":"https://doi.org/10.15407/ujpe68.7.448","url":null,"abstract":"The influence of the magnetic shear on ion drift waves has been investigated for plasmas in the plane slab geometry with a density gradient. A differential equation is derived to describe the mode structure along the density gradient. The magnetic shear localizes the mode around a mode-rational surface, which is perpendicular to the magnetic field. The non-local growth rate turned out to be smaller as compared to the shearless one. The magnetic shear stabilizes long wavelength modes (kρi < 1 ), whereas it destabilizes, as the mode tends toward the short wavelength region, where the density gradient provides a destabilizing effect for the magnetic shear-driven resistive drift mode. However, the effect due to the collision frequency is significantly low in our analysis. The combined effects of E×B flows and the magnetic shear enhance the confinement over a narrow radial region with an internal transport barrier, where stability is attained.","PeriodicalId":23400,"journal":{"name":"Ukrainian Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42068186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Mathematical Models and Methods on Higher Dimensional Bulk Viscous String Cosmology with the Framework of Lyra Geometry Lyra几何框架下高维体粘性弦宇宙学的数学模型与方法
IF 0.5
Ukrainian Journal of Physics Pub Date : 2023-09-08 DOI: 10.15407/ujpe68.7.437
M. Mollah, K.P. Singh, A. J. Meitei, P.R. Singh, A.K. Yadav, S.R. Devi
{"title":"Mathematical Models and Methods on Higher Dimensional Bulk Viscous String Cosmology with the Framework of Lyra Geometry","authors":"M. Mollah, K.P. Singh, A. J. Meitei, P.R. Singh, A.K. Yadav, S.R. Devi","doi":"10.15407/ujpe68.7.437","DOIUrl":"https://doi.org/10.15407/ujpe68.7.437","url":null,"abstract":"We investigate a cosmological scenario generated by a cloud of strings containing particles in the framework of the Lyra geometry by considering five-dimensional Bianchi type-III line element. We assume two physically plausible conditions (i) shear scalar (σ) proportional to the expansion factor (θ), which leads to P = Qn; n ≠ 0 is a constant, P and Q being scale factors and (ii) ξ = ξ0 = constant, ξ being the coefficient of bulk viscosity, deterministic models of our Universe are obtained. We have solved the modified Einstein’s field equations of a homogeneous Bianchi type-III metric. The bihaviors of cosmographic parameters for the different values of time (t) and redshift (z) are presented in detail to study the proposed model. It has been found that the displacement vector (β) behaves itself like the cosmological term, and the solution is consistent with the recent observations of SNeIa. The physical and geometrical properties of the model are premeditated, and it has been discussed in detail regarding the possibilities and prospects that can be happen throughout the evolution of the Universe. It is found that the bulk viscosity plays a crucial role in the evolution of the Universe, and the strings dominate in the early Universe and eventually disappear from the Universe during a sufficiently large time. So, our model can be treated as a realistic one.","PeriodicalId":23400,"journal":{"name":"Ukrainian Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49110318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Микола Петрович Маломуж (до 75-річчя від дня народження) Mikola Petrovich Malomoj（出生75岁）
IF 0.5
Ukrainian Journal of Physics Pub Date : 2023-09-08 DOI: 10.15407/ujpe68.7.503
L. Bulavin, B.A. Veitsman, D. Gavryushenko, M.F. Golovko, V.Ya. Gotsulskyi, V. V. Klepko, I. Koval, M. Lazarenko, M. I. Lebovka, L.M. Lysetskyi, S. Magaz`u, G. Maisano, S.M. Odynaev, Yu. O. Plevachuk, L. M. Sabirov, O. Khorolskyi, K.O. Chalyi, O.V. Chalyi, K.V. Cherevko
{"title":"Микола Петрович Маломуж (до 75-річчя від дня народження)","authors":"L. Bulavin, B.A. Veitsman, D. Gavryushenko, M.F. Golovko, V.Ya. Gotsulskyi, V. V. Klepko, I. Koval, M. Lazarenko, M. I. Lebovka, L.M. Lysetskyi, S. Magaz`u, G. Maisano, S.M. Odynaev, Yu. O. Plevachuk, L. M. Sabirov, O. Khorolskyi, K.O. Chalyi, O.V. Chalyi, K.V. Cherevko","doi":"10.15407/ujpe68.7.503","DOIUrl":"https://doi.org/10.15407/ujpe68.7.503","url":null,"abstract":"<jats:p>-</jats:p>","PeriodicalId":23400,"journal":{"name":"Ukrainian Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48371705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Функція чутливості хемотаксису для системи зі сферичною геометрією 球形几何系统的化学毒性敏感性函数
IF 0.5
Ukrainian Journal of Physics Pub Date : 2023-09-08 DOI: 10.15407/ujpe68.7.456
O.M. Vasyliev, A.O. Slobodianiuk
{"title":"Функція чутливості хемотаксису для системи зі сферичною геометрією","authors":"O.M. Vasyliev, A.O. Slobodianiuk","doi":"10.15407/ujpe68.7.456","DOIUrl":"https://doi.org/10.15407/ujpe68.7.456","url":null,"abstract":"У статтi розв’язується задача визначення функцiї чутливостi хемотаксису для системи, що має геометрiю сфери. Функцiя чутливостi хемотаксису використовується як характеристика неоднорiдностi розподiлу бактерiй в системi, де є атрактант. За наявностi атрактанту бактерiї розподiляються в системi вiдповiдно до розподiлу атрактанту. При цьому важливу роль вiдiграє геометрiя системи, межовi умови, режим пiдведення атрактанту та регулювання кiлькостi бактерiй в системi. Нами розглядається система, в якiй бактерiї розподiленi по поверхнi сфери. Концентрацiя атрактанту в системi регулюється шляхом фiксацiї концентрацiї атрактанту на полюсах сфери з використанням тонкого капiляру. Кiлькiсть бактерiй в системi вважається фiксованою. Для такої системи отримується аналiтичний вираз для функцiї чутливостi хемотаксису. Отриманi результати можуть бути корисними при поясненнi поведiнки бактерiй в реальних системах зi складною геометрiєю та при обробленнi експериментальних даних.","PeriodicalId":23400,"journal":{"name":"Ukrainian Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48688501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Керування інтенсивністю лазерного випромінювання у рідкокристалічних вентилях при записі об’ємної динамічної ґратки
IF 0.5
Ukrainian Journal of Physics Pub Date : 2023-09-08 DOI: 10.15407/ujpe68.7.474
V. Mystetskyi, S. Bugaychuk
{"title":"Керування інтенсивністю лазерного випромінювання у рідкокристалічних вентилях при записі об’ємної динамічної ґратки","authors":"V. Mystetskyi, S. Bugaychuk","doi":"10.15407/ujpe68.7.474","DOIUrl":"https://doi.org/10.15407/ujpe68.7.474","url":null,"abstract":"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000Експериментальнi дослiдження номiнально чистих нематичних рiдких кристалiв (НРК) пiдтверджують запис динамiчних голографiчних ґраток у комiрках як з гомеотропною орiєнтацiєю, так i з планарною. Пояснення можна знайти, виходячи iз фоторефрактивного механiзму запису ґратки, особливiстю якого являється формування нерiвноважного заряду на поверхнi пiдкладинки комiрки пiд дiєю просторово неоднорiдного свiтлового поля. Поява внутрiшнього тангенцiального електричного поля (вздовж пiдкладинок комiрки), разом iз зовнiшнiм електричним полем, що прикладається нормально до пiдкладинок комiрки, вiдкриває додатковi можливостi у керуваннi напрямку вектора результуючого електричного поля. В данiй роботi розроблена i аналiзується модель змiни iнтенсивностей лазерних променiв при їх самодифракцiї i дифракцiї на динамiчнiй ґратцi, створенiй в НРК. Динамiчна фазова ґратка формується завдяки орiєнтацiйному механiзму двозаломлення в НРК при двопучковiй взаємодiї лазерних променiв, що утворюють просторово перiодичну iнтерференцiйну картину дiючого свiтлового поля. Результати проведених розрахункiв вихiдних iнтенсивностей лазерних променiв в перших порядках самодифракцiї i дифракцiї добре узгоджуються з експериментальними вимiрюваннями. Зокрема, вони пояснюють залежнiсть дифракцiйної ефективностi вiд величини зовнiшньої прикладеної напруги, що має добре виражений максимум.\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000","PeriodicalId":23400,"journal":{"name":"Ukrainian Journal of Physics","volume":"17 4","pages":""},"PeriodicalIF":0.5,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41307827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Thermodynamic Quantities of Morse Fluids in the Supercritical Region 超临界区域莫尔斯流体的热力学量
IF 0.5
Ukrainian Journal of Physics Pub Date : 2023-08-23 DOI: 10.15407/ujpe68.6.383
I. V. Pylyuk, M. P. Kozlovskii, O. Dobush
{"title":"Thermodynamic Quantities of Morse Fluids in the Supercritical Region","authors":"I. V. Pylyuk, M. P. Kozlovskii, O. Dobush","doi":"10.15407/ujpe68.6.383","DOIUrl":"https://doi.org/10.15407/ujpe68.6.383","url":null,"abstract":"The critical point parameters for liquid alkali metals (sodium and potassium) are calculated accounting for the non-Gaussian order parameter fluctuations and the Morse interaction potential. The behavior of the isothermal compressibility, density fluctuations, and thermal expansion for sodium is studied in the supercritical temperature region. A significant increase in the isothermal compressibility and the density fluctuations near the critical point indicates a substantial density sensitivity to tiny pressure fluctuations. The thermal expansion coefficient for various fixed pressure values shows a typical gas decrease with increasing supercritical temperature. The Widom line separating the gaseous and liquid structures of the fluid at temperatures above the critical one is represented. Note that our calculations are valid in a small neighborhood of the critical point, which is problematic for theoretical and experimental studies.","PeriodicalId":23400,"journal":{"name":"Ukrainian Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2023-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48593257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Formation of Hydrogen Bonds and Vibrational Processes in Dimethyl Sulfoxide and Its Aqueous Solutions: Raman Spectroscopy and Ab Initio Calculations 二甲基亚砜及其水溶液中氢键的形成和振动过程：拉曼光谱和从头算
IF 0.5
Ukrainian Journal of Physics Pub Date : 2023-08-23 DOI: 10.15407/ujpe68.6.375
A. Jumabaev, H. Hushvaktov, B. Khudaykulov, A. Absanov, M. Onuk, I. Doroshenko, L. Bulavin
{"title":"Formation of Hydrogen Bonds and Vibrational Processes in Dimethyl Sulfoxide and Its Aqueous Solutions: Raman Spectroscopy and Ab Initio Calculations","authors":"A. Jumabaev, H. Hushvaktov, B. Khudaykulov, A. Absanov, M. Onuk, I. Doroshenko, L. Bulavin","doi":"10.15407/ujpe68.6.375","DOIUrl":"https://doi.org/10.15407/ujpe68.6.375","url":null,"abstract":"The intermolecular interaction in dimethyl sulfoxide (DMSO), which is a strong solvent, and its manifestation in vibrational spectra are studied by means of Raman spectroscopy and ab initio calculations. The optimal structure and vibrational spectra of DMSO monomer, dimer, and trimer, as well as complexes of DMSO with water molecules, are calculated, and the potential energy distribution (PED) analysis is carried out. In the Raman spectra of DMSO and its water solutions, a red shift of the S=O stretching band due to the conventional hydrogen bonding and a blue shift of the C–H stretching band due to non-classical hydrogen bonding are detected. The MEP surfaces (changes in the charge distribution) of DMSO monomer, dimer, and DMSO–water cluster are plotted.","PeriodicalId":23400,"journal":{"name":"Ukrainian Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2023-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43534503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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