Physics of Particles and Nuclei Letters最新文献

{"title":"The Casimir Eigenvalues on (a{{d}^{{ otimes k}}}) of su(N) are Linear on N","authors":"R. L. Mkrtchyan","doi":"10.1134/S1547477125702012","DOIUrl":"10.1134/S1547477125702012","url":null,"abstract":"<p>We consider eigenvalues of the Casimir operator on the naturally defined <i>stable sequences</i> of representations of <span>(su(N))</span> algebra and prove that eigenvalues are linear over <i>N</i> iff <span>({{lambda }_{1}} + 2{{lambda }_{2}} + ... + k{{lambda }_{k}} = )</span> <span>({{lambda }_{{N - 1}}} + 2{{lambda }_{{N - 2}}} + ... + k{{lambda }_{{N - k}}})</span>, where <span>({{lambda }_{i}})</span> are Dynkin labels, and <span>({{lambda }_{i}} = 0)</span> for <span>(k &lt; i &lt; N - k)</span>, with fixed <span>(k)</span>. These representations are exactly those which appear in the decomposition of <span>(ad{{(su(N))}^{{ otimes k}}})</span>, therefore this linearity admits the presentation of eigenvalues in the universal, in Vogel’s sense, form, and supports the hypothesis of universal decomposition of <span>(a{{d}^{{ otimes k}}})</span> into Casimir eigenspaces.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":"23 2","pages":"127 - 130"},"PeriodicalIF":0.4,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147667766","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}

{"title":"Charged Scalar Bosons under Rotation and Acceleration","authors":"M. Bordag,&nbsp;D. N. Voskresensky","doi":"10.1134/S1547477125702036","DOIUrl":"10.1134/S1547477125702036","url":null,"abstract":"<p>Creation of charged spinless bosons from vacuum in the rigidly rotating frame is studied in presence of the external static electromagnetic fields, being formed either in the resting, or in the general rotating or in the local-flat frames. It is shown that the description remains the same in the resting and the local-flat frames. More specifically, the case of a solenoid (magnetic flux tube) embedded into the rotating empty cylinder (rotation frame) is studied in presence or absence of a static square electric potential well <span>(e{{A}_{0}})</span>. A supervortex of a spinless-boson field can be created from vacuum when the rotation frequency exceeds a critical value <span>({{Omega }_{{text{c}}}})</span>. It is shown that <span>({{Omega }_{{text{c}}}})</span> is smaller provided the solenoid rests in the resting frame. Then the case is considered when the rotating frame additionally moves with acceleration <span>(vec {w}({kern 1pt} vec {r}{kern 1pt} ') ne 0)</span>. A specific case <span>(w(r) = {G mathord{left/ {vphantom {G r}} right. kern-0em} r})</span> for <span>(G = {text{const}})</span> is treated explicitly. It is shown that for <span>(G &lt; 0)</span> the charged spinless-boson vortex can be created in rapidly rotating system even in the limit when the magnetic and electric fields tend to zero.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":"23 2","pages":"139 - 146"},"PeriodicalIF":0.4,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147667767","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}

{"title":"Development of a Shaper of Short Bipolar Pulses","authors":"O. L. Seroshtanov,&nbsp;V. V. Kobets,&nbsp;A. A. Ulankin","doi":"10.1134/S1547477125702073","DOIUrl":"10.1134/S1547477125702073","url":null,"abstract":"<p>Currently, the LINAC-200 linear electron accelerator is under commissioning at the Laboratory of Nuclear Problems [1]. The RF power supply system of the LINAC-200 accelerator has been designed using TH2129 type klystrons, whose maximum voltage, according to the data sheet specification, is 240 kV. The existing klystron power supply system can only provide 2/3 of the maximum supply voltage, which also limits maximum power of the klystrons. The circuit design solutions that allow an increase in the voltage on the klystron power supply modulator are studied. A unique shaper of short bipolar pulses for switching cell drivers has been developed as a power control system.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":"23 2","pages":"181 - 184"},"PeriodicalIF":0.4,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147667768","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}

{"title":"Proposal for an Optically Pumped 3He++ Polarized Ion Source Development for the NICA Collider","authors":"A. N. Zelenski,&nbsp;V. V. Fimushkin,&nbsp;A. S. Belov,&nbsp;V. P. Ovsyannikov,&nbsp;Yu. N. Filatov,&nbsp;N. V. Dunin,&nbsp;K. A. Ivshin,&nbsp;A. Yu. Ramzdorf,&nbsp;A. N. Solovev,&nbsp;I. S. Yudin","doi":"10.1134/S1547477125702115","DOIUrl":"10.1134/S1547477125702115","url":null,"abstract":"<p>A proposal for development of a high intensity polarized source of ³He⁺⁺ ions is based on injection of polarized by metastability exchange optical pumping (MEOP) technique ³He gas into the EBIS (electron beam ion source) for ionization and accumulation of ³He⁺⁺ ions. A high magnetic field of ~5.0 T in the source should preserve the polarization during ionization process. This paper presents a scheme of the EBIS for ³He⁺⁺ ions production, magnetic field configuration, electron gun, electron beam focusing system, injection system to the source drift tube, which also works as a storage cell to increase ionization efficiency, the ³He cryogenic gas purification and storage system. It will also be possible to inject other gases into this source by a pulse valve into the drift-tube (storage cell) and produce multicharged ions, including Xe²⁸⁺ ions. With the addition of external injection of a single-charge solid heavy ion beam into the EBIS, this source can also produce multicharged ion beams up to Au³³⁺ and Bi³⁸⁺ with a full charge of more than 10 nC/cycle.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":"23 2","pages":"202 - 205"},"PeriodicalIF":0.4,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147667775","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}

{"title":"Development of a Beam Diagnostics Method Based on Pick-Up Electrode Signal Analysis: Bench Test Results","authors":"L. A. Pavlov,&nbsp;I. V. Kalagin,&nbsp;S. V. Mitrofanov,&nbsp;V. A. Semin,&nbsp;V. I. Lisov","doi":"10.1134/S1547477125702152","DOIUrl":"10.1134/S1547477125702152","url":null,"abstract":"<p>One important area of accelerator technology is the development of methods for the diagnostics of charged particle beams. In this paper, we present a system developed at the Laboratory of Nuclear Reactions at the Joint Institute for Nuclear Research, which facilitates the online monitoring of the beam characteristics in the synchrotron accelerator chamber.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":"23 2","pages":"222 - 225"},"PeriodicalIF":0.4,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147667857","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}

{"title":"Nuclear Structure and Shape Dynamics of 194Po in the Framework of IBM-1 and VMI-Based Models","authors":"Farah Riyadh Abbas,&nbsp;A. K. Aobaid","doi":"10.1134/S1547477125702024","DOIUrl":"10.1134/S1547477125702024","url":null,"abstract":"<p>The structural properties of the even–even nucleus ¹⁹⁴Po have been investigated using the Interacting Boson Model (IBM-1), the Variable Moment of Inertia (VMI) model, and its generalized extension (GVMI). Available experimental level energies were used as input data, and additional observables—excitation energies, energy ratios, reduced electric transition probabilities <i>B</i>(<i>E</i>2), and electric quadrupole moments (<span>({{Q}_{l}})</span>)—were calculated with the IBMT.FOR code. The IBM-1 Hamiltonian was diagonalized for <i>N</i> = 9 bosons, with effective charges fitted via the B(E2).dat input scheme. The results show that IBM-1 reproduces the low-spin spectrum and transition rates well, while VMI and GVMI better capture the upward curvature of the ground band at higher spin. The experimental energy ratios (<i>R</i>_4/2 = 2.15, <i>R</i>_6/2 = 3.59, <i>R</i>_8/2 = 3.66) lie close to the <i>SU</i>(5) vibrational limit and far from the <i>SU</i>(3) rotor, placing ¹⁹⁴Po on the <i>SU</i>(5)–<i>O</i>(6) side of the Casten triangle. The <i>B</i>(<i>E</i>2) data are reproduced within ~20%, while the model predicts a distinctive rise–collapse–recovery pattern at higher spin due to <i>SU</i>(5)–O(6) interference. For the reduced transition probability, the experimental value of <i>B</i>(<i>E</i>2; <span>(~2_{1}^{ + })</span> → <span>(~0_{1}^{ + })</span>) was 0.2225 e²b², while the theoretical calculation yielded a value of 0.18 e²b². The calculated quadrupole moments <i>Q</i> of the five 2⁺ states exhibit alternating signs, consistent with γ softness and strong state mixing. It was found that the experimental value of <i>Q</i> is 5.5 eb, which is in excellent agreement with the theoretical prediction of 5.5 eb. For ¹⁹⁴Po, the ground-state and γ-bands were analyzed using IBM-1, VMI, and GVMI models, enabling the prediction of levels not yet experimentally confirmed. Several tentative experimental values were supported by the models, with VMI and GVMI showing the closest agreement (χ² = 0.000091 and 0.000001, respectively). The IBM-1 framework, supported by VMI/GVMI trends, provides a reliable description of its structure, while the predicted high-spin <i>B</i>(<i>E</i>2) transitions and quadrupole moments remain decisive tests for future experiments.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":"23 2","pages":"131 - 138"},"PeriodicalIF":0.4,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147667810","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}

{"title":"Nonlocal Velocity-Dependent Optical Potential and the Perey Effect: The Incident Proton Case","authors":"Mohammad Fatehi Hasan","doi":"10.1134/S1547477125702164","DOIUrl":"10.1134/S1547477125702164","url":null,"abstract":"<p>In the nucleus interior, the presence of a nonlocal potential leads to suppression or enhancement of the wave functions that differ from the corresponding wave functions obtained by a local potential. This is known as the Perey effect. In this work, we utilize the calculated Perey damping factor to demonstrate that the nonlocal velocity-dependent optical potential simulates a source of nonlocality. In that regard, we considered proton scattering from ¹²C, ¹⁶O, ⁴⁰Ca, ⁵⁸Ni, and ¹²⁰Sn in the energy range between 10–40 MeV. The Perey damping factor is calculated for each nucleus at each incident proton energy and for different angular momentum quantum numbers to assess the nonlocality strength resulting from the velocity-dependent nonlocal optical potential. The potential parameters required to determine the local and the nonlocal wave functions, and therefore the Perey damping factors, are obtained from different articles. In one case, the required potential parameters were obtained by fitting these parameters to the experimental angular distributions using a least-square fit analysis. Our results demonstrate that the effect of the nonlocal potential is dependent on the target and is dependent on both energy and orbital angular momentum for each target.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":"23 2","pages":"226 - 239"},"PeriodicalIF":0.4,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147667809","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}

{"title":"Siberian Snakes Based on Transverse Magnetic Fields to Preserve and Control Proton Polarization in the NICA Collider","authors":"E. D. Tsyplakov,&nbsp;Yu. N. Filatov,&nbsp;A. M. Kondratenko,&nbsp;M. A. Kondratenko,&nbsp;A. V. Butenko,&nbsp;V. P. Ladygin,&nbsp;V. A. Lebedev,&nbsp;E. M. Syresin,&nbsp;E. A. Butenko","doi":"10.1134/S1547477125702097","DOIUrl":"10.1134/S1547477125702097","url":null,"abstract":"<p>Siberian snakes based on helix and dipole magnets have been proposed to preserve proton polarization during acceleration in the NICA collider and to control the polarization direction throughout the entire energy range of the experiment. Unlike a solenoidal snake, whose field integral increases proportionally with momentum, the field integral in these snakes on transverse fields remains nearly constant with increasing energy. The advantages of the proposed snakes include their compactness and acceptable closed-orbit deviations at low energies. The results of numerical simulations of spin dynamics during proton acceleration up to 13.5 GeV in the NICA accelerator complex are presented.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":"23 2","pages":"190 - 195"},"PeriodicalIF":0.4,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147667826","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}

{"title":"Highly Superperiodic Structure of the Nuclotron with Quasi-Frozen Spin for Studying the Electric Dipole Moment of Light Nuclei","authors":"Yu. V. Senichev,&nbsp;S. D. Kolokolchikov,&nbsp;A. E. Aksentyev,&nbsp;A. A. Melnikov,&nbsp;N. N. Nikolaev,&nbsp;V. P. Ladygin,&nbsp;E. M. Syresin","doi":"10.1134/S1547477125702127","DOIUrl":"10.1134/S1547477125702127","url":null,"abstract":"<p>The task of adapting the Nuclotron structure to the requirements for the structure for measuring the electric dipole moment of the deuteron and proton can be determined by a set of problems of spin-orbit motion: the presence of straight sections with dispersion for placing three families of sextupoles that suppress the decoherence of the spin precession and maintain the spin direction along the ring. High superperiodicity of the developed quasi-frozen structure is necessary for the proton beam due to the high anomaly of the magnetic dipole moment of the proton. The goal of the proposed work is to determine the relationship between the Nuclotron and the NICA collider, including a modification of the Nuclotron magneto-optical structure to create a synchrotron with two functions in one accelerator: a booster of polarized proton and deuteron beams for injection into the collider and an independent synchrotron-storage ring for conducting precision experiments on the study of the EDM of light nuclei and the search for an axion.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":"23 2","pages":"206 - 210"},"PeriodicalIF":0.4,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147667828","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}

{"title":"In Situ Mapping of Space Charge Region Activation Dynamics in SiC/Si-Based Heterostructures by KPFM/STS: Role of Interface State Recharging","authors":"M. V. Dolgopolov,&nbsp;N. A. Ivliev,&nbsp;V. V. Radenko,&nbsp;B. S. Radzhapov,&nbsp;S. A. Radzhapov,&nbsp;A. S. Chipura","doi":"10.1134/S1547477125702176","DOIUrl":"10.1134/S1547477125702176","url":null,"abstract":"<p>This work presents a novel combined method for the in situ analysis of electronic properties of SiC/Si heterojunctions with submicron resolution (30 nm), integrating Kelvin probe force microscopy (KPFM) and scanning tunneling spectroscopy (STS). For the first time, we have experimentally discovered a threshold activation effect of the space charge region (SCR) with a characteristic delay time of 2.3 ± 0.5 s and nonexponential work function relaxation (τ = 35 ± 2 s, β = 0.65 ± 0.05), indicating an energy distribution of interface states with a characteristic energy of 0.12 eV. A quantitative correlation between interface morphology and spatial distribution of the density of states (<span>({{D}_{{{text{it}}}}})</span>) has been established, showing a fivefold increase of <span>({{D}_{{{text{it}}}}})</span> in dislocation areas (&gt;5 × 10¹² cm^–2 eV^–1) compared to atomically smooth terraces. A physical model linking the <span>({{D}_{{{text{it}}}}}(x))</span> gradient with nonlinear band curving in the depletion region has been developed. Specific engineering solutions for radiation-hard converters are proposed: contact geometry optimization (30% reduction of fringe fields), <span>({text{A}}{{{text{l}}}_{{text{2}}}}{{{text{O}}}_{{text{3}}}})</span> passivation (40% Schottky barrier reduction), and doping for relaxation time control. The results enable the targeted improvement of betavoltaic cell efficiency and the sensitivity of ionizing radiation detectors.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":"23 2","pages":"240 - 250"},"PeriodicalIF":0.4,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147667770","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}