发布求助
文献互助 智能选刊 最新文献

Journal of Contemporary Physics (Armenian Academy of Sciences)最新文献

筛选
英文 中文
Horizontal and Vertical Profiling of the Proton Beam of Cyclotron C18/18 by Vibrating Wire Monitors of Modernized Diagnostic Station 现代化诊断站振动线监测C18/18回旋加速器质子束水平和垂直剖面
IF 0.5 4区 物理与天体物理
Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2025-03-16 DOI: 10.1134/S1068337225700082
S. G. Arutunian, A. P. Aprahamian, A. V. Margaryan, L. M. Lazarev, N. M. Manukyan, G. V. Mirzoyan, E. G. Lazareva, R. S. Gevorgyan, A. A. Manukyan, M. Chung
{"title":"Horizontal and Vertical Profiling of the Proton Beam of Cyclotron C18/18 by Vibrating Wire Monitors of Modernized Diagnostic Station","authors":"S. G. Arutunian,&nbsp;A. P. Aprahamian,&nbsp;A. V. Margaryan,&nbsp;L. M. Lazarev,&nbsp;N. M. Manukyan,&nbsp;G. V. Mirzoyan,&nbsp;E. G. Lazareva,&nbsp;R. S. Gevorgyan,&nbsp;A. A. Manukyan,&nbsp;M. Chung","doi":"10.1134/S1068337225700082","DOIUrl":"10.1134/S1068337225700082","url":null,"abstract":"<p>The horizontal and vertical profiles of the proton beam of the cyclotron C18/18 were measured by a modernized diagnostic station based on vibrating wire monitors. Considering the results of the first experiments using monitors with an aperture of 14 mm and superimposed lead screens, monitors with an extended aperture (28 mm) and magnets removed from the beam exposure zone were developed. In addition, the sensors are assembled on a thick metal base that serves as a collimator for the beam. The problems of electromagnetic interference are solved by the fact that the electronic nodes of the station are assembled on the same base. Scanning in the new station is carried out in the same plane, as close as possible to the output flange of the cyclotron (54 mm). New software has been developed that normalizes the profiles by the maximum value. Test measurements of the proton beam profile in the range of the average beam current ~1 μA were carried out.</p>","PeriodicalId":623,"journal":{"name":"Journal of Contemporary Physics (Armenian Academy of Sciences)","volume":"59 4","pages":"359 - 365"},"PeriodicalIF":0.5,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632584","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
Polarimetric Light-Pulse Atom Interferometer: Two-Level Scheme 偏振光脉冲原子干涉仪：双能级方案
IF 0.5 4区 物理与天体物理
Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2025-03-16 DOI: 10.1134/S1068337225700185
A. Zh. Muradyan
{"title":"Polarimetric Light-Pulse Atom Interferometer: Two-Level Scheme","authors":"A. Zh. Muradyan","doi":"10.1134/S1068337225700185","DOIUrl":"10.1134/S1068337225700185","url":null,"abstract":"<p>A new type of atomic interferometer is proposed, in which the traditional method of measuring the state of an atom is replaced by the technique of polarization spectroscopy using the working substance of a clot of condensate of two-level atoms. As a result, the atomic interferometer is freed from needing the above-mentioned multiple repetitions, while maintaining high sensitivity. The Kapitsa-Dirac resonance diffraction is used to split the translational motion of the atom. Numerical computations to determine the rotated component of the probing field show that the ratio of the output signal to the input signal under normal conditions in a specialized laser physics laboratory using a clot of atomic condensate of alkali metals with a concentration of <span>({{10}^{{11}}})</span> cm<sup>–3</sup> and linear dimensions of the order of 1 μm as the working substance reaches quite respectable values.</p>","PeriodicalId":623,"journal":{"name":"Journal of Contemporary Physics (Armenian Academy of Sciences)","volume":"59 4","pages":"371 - 377"},"PeriodicalIF":0.5,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632582","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
Bremsstrahlung of Electrons in Water in Contact with Materials Containing Radioactive Impurities 与含有放射性杂质的物质接触的水中电子的轫致辐射
IF 0.5 4区 物理与天体物理
Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2025-03-16 DOI: 10.1134/S1068337225700100
R. N. Balasanyan, I. G. Grigoryan, P. H. Muzhikyan, R. B. Kostanyan
{"title":"Bremsstrahlung of Electrons in Water in Contact with Materials Containing Radioactive Impurities","authors":"R. N. Balasanyan,&nbsp;I. G. Grigoryan,&nbsp;P. H. Muzhikyan,&nbsp;R. B. Kostanyan","doi":"10.1134/S1068337225700100","DOIUrl":"10.1134/S1068337225700100","url":null,"abstract":"<p>Changes in the intensity of electron bremsstrahlung radiation when samples of metallic tungsten and optical glass containing radioactive impurities are immersed in water were experimentally studied. The bremsstrahlung intensity measurements were performed on a gamma-ray spectrometer. The results of experimental measurements performed on a pure tungsten sample are also presented for comparison. It has been shown that when materials with a radioactive impurity subject to β<sup>−</sup>-decay come into contact with water, X-ray radiation with an energy of 5.67 keV is generated. However, similar interactions involving materials with radioactive impurities undergoing α-decay do not generate bremsstrahlung radiation.</p>","PeriodicalId":623,"journal":{"name":"Journal of Contemporary Physics (Armenian Academy of Sciences)","volume":"59 4","pages":"366 - 370"},"PeriodicalIF":0.5,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632587","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
Three-Mode Entangled States of the Field in the Process of Nondegenerate Parametric Decay in an Optical Resonator 光学谐振腔中非简并参量衰减过程中场的三模纠缠态
IF 0.5 4区 物理与天体物理
Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2025-03-16 DOI: 10.1134/S1068337225700112
S. T. Gevorgyan, M. S. Gevorgyan
{"title":"Three-Mode Entangled States of the Field in the Process of Nondegenerate Parametric Decay in an Optical Resonator","authors":"S. T. Gevorgyan,&nbsp;M. S. Gevorgyan","doi":"10.1134/S1068337225700112","DOIUrl":"10.1134/S1068337225700112","url":null,"abstract":"<p>For the process of non-degenerate parametric decay in an optical resonator, in which a quantum with energy <span>(hbar {{{{omega }}}_{3}})</span> decays into two quanta with energies <span>(hbar {{{{omega }}}_{2}})</span> and <span>(hbar {{{{omega }}}_{1}})</span>, where <span>(hbar {{{{omega }}}_{3}} = hbar {{{{omega }}}_{2}} + hbar {{{{omega }}}_{1}})</span> is the possibility of forming entangled states of the field by variables of the number of photons between interacting modes of the optical system is investigated. For this purpose, we investigated the dynamics of normalized correlation functions of fluctuations of the number of photons of interacting modes using a Monte–Carlo method. It is shown that in the stationary interaction limit, the value of these correlation functions strongly depends on the value of the coupling coefficient between the modes. It is shown that strong entanglement of the state of three interacting field modes is obtained in the case of weak coupling between the modes. In the case of extreme coupling between them, the value of the correlation function of fluctuations of the number of photons of the field modes tends to unity, because of which entanglement between the states of the modes disappears.</p>","PeriodicalId":623,"journal":{"name":"Journal of Contemporary Physics (Armenian Academy of Sciences)","volume":"59 4","pages":"391 - 395"},"PeriodicalIF":0.5,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632585","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
Response Latencies of Visually Sensitive Neurons in Area 21a of the Cortex 脑皮层21a区视觉敏感神经元的反应潜伏期
IF 0.5 4区 物理与天体物理
Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2025-03-16 DOI: 10.1134/S1068337225700173
D. K. Khachvankyan, A. A. Meliksetyan, V. V. Nalbandyan
{"title":"Response Latencies of Visually Sensitive Neurons in Area 21a of the Cortex","authors":"D. K. Khachvankyan,&nbsp;A. A. Meliksetyan,&nbsp;V. V. Nalbandyan","doi":"10.1134/S1068337225700173","DOIUrl":"10.1134/S1068337225700173","url":null,"abstract":"<p>The paper presents the results of a study on the duration of latent periods (LP) of responses from single neurons in region 21a after their receptive fields (RF) are triggered by stationary flashing visual stimuli. Neurons exhibiting only ON or OFF responses demonstrate markedly reduced fluctuations in LP duration, and the mean LP duration in these neurons is much lower compared to those with ON-OFF responses. A reduced fluctuation in LP duration was noted in neurons exhibiting a tonic response pattern, which also displayed the shortest average LP duration. The most significant variations in LP durations and the highest average values were seen in ON–OFF neurons exhibiting a phasic response pattern. In only one-third of the examined neurons, the length of LP remains constant across the whole RF area; in the majority of neurons, it fluctuates based on the stimulus’s location inside the RF. The disparity in LP duration within a single RF can attain a factor of three or greater. It was also determined that the majority of neurons exhibit a significant degree of independence in the variations of LP ON and OFF components of ON–OFF responses. The acquired results suggest that the majority of RF neurons 21a area possess not only a complicated spatial organization but also an inhomogeneous discrete temporal structure.</p>","PeriodicalId":623,"journal":{"name":"Journal of Contemporary Physics (Armenian Academy of Sciences)","volume":"59 4","pages":"413 - 419"},"PeriodicalIF":0.5,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632549","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
The Reconstruction of Long-Lived Particles in the CMS (LHC) Experiment 长寿命粒子在CMS （LHC）实验中的重构
IF 0.5 4区 物理与天体物理
Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2025-03-16 DOI: 10.1134/S1068337225700148
A. A. Hayrapetyan
{"title":"The Reconstruction of Long-Lived Particles in the CMS (LHC) Experiment","authors":"A. A. Hayrapetyan","doi":"10.1134/S1068337225700148","DOIUrl":"10.1134/S1068337225700148","url":null,"abstract":"<p>An algorithm has been developed for reconstructing long-lived particles (LLP) decaying in the barrel and endcap regions of the muon system of the CMS detector at the Large Hadron Collider. Calculations were done on the basis of Monte Carlo simulated data using CMSSW package, adapted to the conditions of CMS detector experimental setup of 2018. In considered process the hypothetical LLP particles are produced from decays of B mesons in proton–proton (p–p) collisions at a center-of-mass energy of 13 TeV. Decays of LLP particles in the muon system of the CMS detector are characterized by the presence of wide showers with a large multiplicity of hits from the muon chamber channels, which differs significantly from the hits of known particles, and is a good criterion for identifying LLP particles.</p>","PeriodicalId":623,"journal":{"name":"Journal of Contemporary Physics (Armenian Academy of Sciences)","volume":"59 4","pages":"353 - 358"},"PeriodicalIF":0.5,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632583","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
Sectorial Ground-State Nondegeneracy in Majorana Chains with Interaction and Orthogonal Symmetry 具有相互作用和正交对称的Majorana链的扇形基态非简并性
IF 0.5 4区 物理与天体物理
Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2025-03-16 DOI: 10.1134/S1068337225700136
T. S. Hakobyan
{"title":"Sectorial Ground-State Nondegeneracy in Majorana Chains with Interaction and Orthogonal Symmetry","authors":"T. S. Hakobyan","doi":"10.1134/S1068337225700136","DOIUrl":"10.1134/S1068337225700136","url":null,"abstract":"<p>Various quantum chains consisting of interacting Majorana fermions with flavors are constructed. These systems are invariant with respect to the rotations and reflections in the flavor space. The entire space of states splits into sectors characterized by a specific set of fermionic parities related to different flavors. All systems under consideration satisfy the Lieb-Mattis condition. As a result, the lowest-energy states within individual sectors are nondegenerate. The sectorial ground states are combined into antisymmetric (in flavor numbers) multiplets.</p>","PeriodicalId":623,"journal":{"name":"Journal of Contemporary Physics (Armenian Academy of Sciences)","volume":"59 4","pages":"437 - 444"},"PeriodicalIF":0.5,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632547","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
Impurity States in a Quasi-Conical Quantum Dot 准圆锥量子点中的杂质态
IF 0.5 4区 物理与天体物理
Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2025-03-16 DOI: 10.1134/S1068337225700161
Kh. S. Khachatryan, M. A. Mkrtchyan
{"title":"Impurity States in a Quasi-Conical Quantum Dot","authors":"Kh. S. Khachatryan,&nbsp;M. A. Mkrtchyan","doi":"10.1134/S1068337225700161","DOIUrl":"10.1134/S1068337225700161","url":null,"abstract":"<p>Donor impurity states in a quasi-conical quantum dot are theoretically investigated. The confinement potential is considered within the framework of the model with infinite walls. The problem is considered because the impurity is located at the vertex of a quasi-conical quantum dot. Based on the hydrogen atom model, the impurity and the electron’s interaction potential is Coulomb potential. Because of the complexity, the problem is solved using the approximate finite element method (FEM). The FEM method is used to compute the energy states and wave functions of the system both in the presence and absence of the donor impurity. Based on the obtained results, the dependences of the impurity binding energy on the geometric parameters of the quasi-conical quantum dot and the probability density of the electron cloud distribution in the quantum dot are studied.</p>","PeriodicalId":623,"journal":{"name":"Journal of Contemporary Physics (Armenian Academy of Sciences)","volume":"59 4","pages":"396 - 400"},"PeriodicalIF":0.5,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632334","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
On the Output Vacuum Windows of Accelerator Facilities Used in the AANL (YerPhI) Experiments 在AANL （YerPhI）实验中使用的加速器设备的输出真空窗
IF 0.5 4区 物理与天体物理
Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2025-03-16 DOI: 10.1134/S1068337225700239
L. R. Vahradyan, A. S. Hakobyan, L. A. Poghosyan, G. D. Movsesyan, H. H. Marukyan
{"title":"On the Output Vacuum Windows of Accelerator Facilities Used in the AANL (YerPhI) Experiments","authors":"L. R. Vahradyan,&nbsp;A. S. Hakobyan,&nbsp;L. A. Poghosyan,&nbsp;G. D. Movsesyan,&nbsp;H. H. Marukyan","doi":"10.1134/S1068337225700239","DOIUrl":"10.1134/S1068337225700239","url":null,"abstract":"<p>The energy losses of charged particles passing through the vacuum-tight exit windows of the operating accelerator facilities where experiments are carried out at the AANL (YerPhI), have been determined. Computation tables and graphs of the dependencies of the energy loss of the accelerated beam on its kinetic energy, the thickness of foils made of materials used in the separation windows, and the distances from the windows to the targets in the air are given.</p>","PeriodicalId":623,"journal":{"name":"Journal of Contemporary Physics (Armenian Academy of Sciences)","volume":"59 4","pages":"450 - 457"},"PeriodicalIF":0.5,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632544","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
On the Threshold of Mechanical Freedericksz Transition in the Liquid Crystalline Elastomer 液晶弹性体力学Freedericksz转变阈值的研究
IF 0.5 4区 物理与天体物理
Journal of Contemporary Physics (Armenian Academy of Sciences) Pub Date : 2025-03-16 DOI: 10.1134/S1068337225700240
M. R. Hakobyan, R. S. Hakobyan
{"title":"On the Threshold of Mechanical Freedericksz Transition in the Liquid Crystalline Elastomer","authors":"M. R. Hakobyan,&nbsp;R. S. Hakobyan","doi":"10.1134/S1068337225700240","DOIUrl":"10.1134/S1068337225700240","url":null,"abstract":"<p>The study of the threshold mechanical transition of Freedericksz is presented for the first time, taking into account the nonlinearity of the interaction of orientational and mechanical anisotropy, using weakly crosslinked nematic elastomers with side chains as an example. The reorientation of the director of the liquid crystal elastomer has a threshold character in cases where the mechanical stress is applied perpendicular to the initial orientation of the liquid crystal director. The threshold of reorientation of the liquid crystal molecules is analytically calculated. The experimental implementation of the proposed approach will allow us to determine one of the coefficients of nonlinear interaction.</p>","PeriodicalId":623,"journal":{"name":"Journal of Contemporary Physics (Armenian Academy of Sciences)","volume":"59 4","pages":"445 - 449"},"PeriodicalIF":0.5,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143632545","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
首页 上一页 下一页 尾页
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整，为了账户安全，请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们：info@booksci.cn Book学术提供免费学术资源搜索服务，方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号：604180095
Book学术官方微信