Pub Date : 2025-02-11DOI: 10.1016/j.nuclphysa.2025.123031
Ashok Kumar Mondal, Sathi Sharma
In this work, we re-evaluate the reaction rate for the 26Si(p,γ)27P process, motivated by discrepancies in previous studies regarding key parameters such as , , ωγ, and the S - factor at zero energy, S(0). Using the NuShellX code with the newly developed USDCm interaction [20], we performed shell model calculations to reproduce energy levels and calculate spectroscopic factors for various states. The gamma width () values for the 3/2+ and 5/2+ states were determined using shell model calculations. Additionally, we employed the WSPOT code to analyze scattering cross-sections and phase shifts to compute the proton width () values. After that, we have calculated the resonance strength (ωγ) values for 3/2+ and 5/2+ states respectively. Here, we have utilized the RADCAP code to calculate the S - factor at zero energy, S(0). Finally, we computed the reaction rates across a temperature range of 0.1 - 2 GK. Our results provide a refined understanding of the 26Si(p,γ)27P reaction rate, addressing inconsistencies in previous studies.
{"title":"Re-evaluation of the 26Si(p,γ)27P astrophysical reaction rate","authors":"Ashok Kumar Mondal, Sathi Sharma","doi":"10.1016/j.nuclphysa.2025.123031","DOIUrl":"10.1016/j.nuclphysa.2025.123031","url":null,"abstract":"<div><div>In this work, we re-evaluate the reaction rate for the <sup>26</sup>Si(p,<em>γ</em>)<sup>27</sup>P process, motivated by discrepancies in previous studies regarding key parameters such as <span><math><msub><mrow><mi>Γ</mi></mrow><mrow><mi>γ</mi></mrow></msub></math></span>, <span><math><msub><mrow><mi>Γ</mi></mrow><mrow><mi>p</mi></mrow></msub></math></span>, <em>ωγ</em>, and the S - factor at zero energy, S(0). Using the NuShellX code with the newly developed USDCm interaction <span><span>[20]</span></span>, we performed shell model calculations to reproduce energy levels and calculate spectroscopic factors for various states. The gamma width (<span><math><msub><mrow><mi>Γ</mi></mrow><mrow><mi>γ</mi></mrow></msub></math></span>) values for the 3/2<sup>+</sup> and 5/2<sup>+</sup> states were determined using shell model calculations. Additionally, we employed the WSPOT code to analyze scattering cross-sections and phase shifts to compute the proton width (<span><math><msub><mrow><mi>Γ</mi></mrow><mrow><mi>p</mi></mrow></msub></math></span>) values. After that, we have calculated the resonance strength (<em>ωγ</em>) values for 3/2<sup>+</sup> and 5/2<sup>+</sup> states respectively. Here, we have utilized the RADCAP code to calculate the S - factor at zero energy, S(0). Finally, we computed the reaction rates across a temperature range of 0.1 - 2 GK. Our results provide a refined understanding of the <sup>26</sup>Si(p,<em>γ</em>)<sup>27</sup>P reaction rate, addressing inconsistencies in previous studies.</div></div>","PeriodicalId":19246,"journal":{"name":"Nuclear Physics A","volume":"1056 ","pages":"Article 123031"},"PeriodicalIF":1.7,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143395325","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}
Pub Date : 2025-02-03DOI: 10.1016/j.nuclphysa.2025.123024
A. Hannaman , B. Harvey , K. Hagel , A.B. McIntosh , A. Abbott , L. Bills , A. Fentress , J. Gauthier , T. Hankins , Y.-W. Lui , L.A. McIntosh , S. Regener , R. Rider , S. Schultz , M.Q. Sorensen , J. Tobar , Z. Tobin , S. Yennello
Ground state nuclei usually have compact geometries. However, there have been theoretical predictions that excited nuclei can take on more extended shapes such as toroids or bubbles. There have been many attempts to identify signatures of such shapes in experimental data. One signature, both predicted by theory and sought by experimental data, is narrow resonances at high excitation energy in peripheral intermediate-energy heavy-ion collisions. Potential evidence for toroidal states was reported in the alpha particle disassembly of 28Si after collision with a 12C target at 35 MeV/nucleon. The prior work was limited by angular resolution and statistical uncertainties. The present work aims to measure the excitation energy distribution for these disassembly events with improved angular resolution and reduced statistical uncertainty using the Forward Array Using Silicon Technology (FAUST). FAUST is equipped with resistive dual-axis duo-lateral (DADL) position-sensitive silicon detectors capable of sub-millimeter position resolution. The measured excitation energy distributions of 7-α disassembly events showed no strong evidence for highly excited states at the cross section and widths suggested by previous experiment. A statistical likelihood analysis was performed to provide an upper limit to toroidal high-spin isomer cross section, as evidenced by this observable, as a function of the excitation energy and width of potential states.
{"title":"Upper bounds on the production cross section of toroidally deformed nuclei","authors":"A. Hannaman , B. Harvey , K. Hagel , A.B. McIntosh , A. Abbott , L. Bills , A. Fentress , J. Gauthier , T. Hankins , Y.-W. Lui , L.A. McIntosh , S. Regener , R. Rider , S. Schultz , M.Q. Sorensen , J. Tobar , Z. Tobin , S. Yennello","doi":"10.1016/j.nuclphysa.2025.123024","DOIUrl":"10.1016/j.nuclphysa.2025.123024","url":null,"abstract":"<div><div>Ground state nuclei usually have compact geometries. However, there have been theoretical predictions that excited nuclei can take on more extended shapes such as toroids or bubbles. There have been many attempts to identify signatures of such shapes in experimental data. One signature, both predicted by theory and sought by experimental data, is narrow resonances at high excitation energy in peripheral intermediate-energy heavy-ion collisions. Potential evidence for toroidal states was reported in the alpha particle disassembly of <sup>28</sup>Si after collision with a <sup>12</sup>C target at 35 MeV/nucleon. The prior work was limited by angular resolution and statistical uncertainties. The present work aims to measure the excitation energy distribution for these disassembly events with improved angular resolution and reduced statistical uncertainty using the Forward Array Using Silicon Technology (FAUST). FAUST is equipped with resistive dual-axis duo-lateral (DADL) position-sensitive silicon detectors capable of sub-millimeter position resolution. The measured excitation energy distributions of 7-<em>α</em> disassembly events showed no strong evidence for highly excited states at the cross section and widths suggested by previous experiment. A statistical likelihood analysis was performed to provide an upper limit to toroidal high-spin isomer cross section, as evidenced by this observable, as a function of the excitation energy and width of potential states.</div></div>","PeriodicalId":19246,"journal":{"name":"Nuclear Physics A","volume":"1056 ","pages":"Article 123024"},"PeriodicalIF":1.7,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143387320","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}
Pub Date : 2025-01-27DOI: 10.1016/j.nuclphysa.2025.123022
L. Ponnath , T. Aumann , C.A. Bertulani , R. Gernhäuser , T. Almusidi , H. Alvarez-Pol , L. Atar , L. Atkins , Y. Ayyad , J. Benlliure , K. Boretzky , M.J.G. Borge , L.T. Bott , G. Bruni , B. Brückner , P. Cabanelas , C. Caesar , E. Casarejos , J. Cederkall , A. Corsi , F. Wamers
The R3B (Reactions with Relativistic Radioactive Beams) experiment as a major instrument of the NUSTAR collaboration for the research facility FAIR in Darmstadt is designed for kinematically complete studies of reactions with high-energy radioactive beams. Part of the broad physics program of R3B is to constrain the asymmetry term in the nuclear equation-of-state and hence improve the description of highly asymmetric nuclear matter (e.g., in neutron stars). For a precise determination of the neutron-skin thickness – an observable which is directly correlated with the symmetry energy in theoretical calculations – by measuring absolute fragmentation cross sections, it is essential to quantify the uncertainty and challenge the reaction model under stable conditions. During the successful FAIR Phase-0 campaign of R3B, we precisely measured the energy dependence of total interaction cross sections in 12C+12C collisions, for a direct comparison with calculations based on the eikonal reaction theory.
{"title":"Precise measurement of nuclear interaction cross sections towards neutron-skin determination with R3B","authors":"L. Ponnath , T. Aumann , C.A. Bertulani , R. Gernhäuser , T. Almusidi , H. Alvarez-Pol , L. Atar , L. Atkins , Y. Ayyad , J. Benlliure , K. Boretzky , M.J.G. Borge , L.T. Bott , G. Bruni , B. Brückner , P. Cabanelas , C. Caesar , E. Casarejos , J. Cederkall , A. Corsi , F. Wamers","doi":"10.1016/j.nuclphysa.2025.123022","DOIUrl":"10.1016/j.nuclphysa.2025.123022","url":null,"abstract":"<div><div>The R<sup>3</sup>B (Reactions with Relativistic Radioactive Beams) experiment as a major instrument of the NUSTAR collaboration for the research facility FAIR in Darmstadt is designed for kinematically complete studies of reactions with high-energy radioactive beams. Part of the broad physics program of R<sup>3</sup>B is to constrain the asymmetry term in the nuclear equation-of-state and hence improve the description of highly asymmetric nuclear matter (e.g., in neutron stars). For a precise determination of the neutron-skin thickness – an observable which is directly correlated with the symmetry energy in theoretical calculations – by measuring absolute fragmentation cross sections, it is essential to quantify the uncertainty and challenge the reaction model under stable conditions. During the successful FAIR Phase-0 campaign of R<sup>3</sup>B, we precisely measured the energy dependence of total interaction cross sections in <sup>12</sup>C+<sup>12</sup>C collisions, for a direct comparison with calculations based on the eikonal reaction theory.</div></div>","PeriodicalId":19246,"journal":{"name":"Nuclear Physics A","volume":"1056 ","pages":"Article 123022"},"PeriodicalIF":1.7,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143211112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-15DOI: 10.1016/j.nuclphysa.2025.123020
F.M. Rafiei, O.N. Ghodsi
This work examines the relation between the bulk incompressibility of nuclear matter, K, and the surface nucleon distribution during the reaction process. Taking into account Pauli exclusion corrections, the double-folding (DF) formalism with the different density-dependent M3Y forces is applied to the analysis of the symmetric reaction of 40Ca+40Ca. Changes in the surface density distributions of protons and neutrons are found to be strongly correlated with changes in the bulk incompressibility. The obtained results suggest that, in addition to the symmetry energy slope, the quantity of neutron skin thickness (NST) may have a correlation with K values when evaluated utilizing heavy ion reactions. This constraint is caused by the influence of the bulk nuclear matter incompressibility on the surface nucleon distribution during the fusion reaction.
{"title":"Investigation of the correlation between the distribution of surface nucleons and incompressibility of nuclear matter in the 40Ca+40Ca reaction","authors":"F.M. Rafiei, O.N. Ghodsi","doi":"10.1016/j.nuclphysa.2025.123020","DOIUrl":"10.1016/j.nuclphysa.2025.123020","url":null,"abstract":"<div><div>This work examines the relation between the bulk incompressibility of nuclear matter, <em>K</em>, and the surface nucleon distribution during the reaction process. Taking into account Pauli exclusion corrections, the double-folding (DF) formalism with the different density-dependent M3Y forces is applied to the analysis of the symmetric reaction of <sup>40</sup>Ca+<sup>40</sup>Ca. Changes in the surface density distributions of protons and neutrons are found to be strongly correlated with changes in the bulk incompressibility. The obtained results suggest that, in addition to the symmetry energy slope, the quantity of neutron skin thickness (NST) may have a correlation with <em>K</em> values when evaluated utilizing heavy ion reactions. This constraint is caused by the influence of the bulk nuclear matter incompressibility on the surface nucleon distribution during the fusion reaction.</div></div>","PeriodicalId":19246,"journal":{"name":"Nuclear Physics A","volume":"1055 ","pages":"Article 123020"},"PeriodicalIF":1.7,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143154197","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}
Pub Date : 2025-01-14DOI: 10.1016/j.nuclphysa.2025.123019
N. Susshma , R. Gowrishankar , S. Deepa , K. Vijay Sai , S. Chatterjee , A. Sharma , S.S. Ghugre , Shabir Dar , S. Das , S. Basu , S. Nandi , S. Bhattacharya , S.S. Nayak , G. Mukherjee , S. Bhattacharyya , R.P. Singh , G.H. Bhat , J.A. Sheikh , S. Jehangir , R. Raut
Two previously known bands in the excitation scheme of the 154Tb nucleus have been investigated for the multipolarity and the electric/magnetic nature of the intra- and inter-band transitions. The excited states of the nucleus were populated in an α-beam induced reaction and the γ-rays emitted therefrom were detected using an array of Compton suppressed HPGe clover detectors. The experimental findings are indicative of a shape evolution of the nucleus and development of strong triaxiality at higher spins. The multipolarities of the inter-band transitions brings forth the same. Total Routhian Surface (TRS) calculations and those in the framework of Triaxial Projected Shell Model (TPSM) have been carried out and the results corroborate the proposition on triaxiality.
{"title":"Shape transition and development of triaxiality in 154Tb","authors":"N. Susshma , R. Gowrishankar , S. Deepa , K. Vijay Sai , S. Chatterjee , A. Sharma , S.S. Ghugre , Shabir Dar , S. Das , S. Basu , S. Nandi , S. Bhattacharya , S.S. Nayak , G. Mukherjee , S. Bhattacharyya , R.P. Singh , G.H. Bhat , J.A. Sheikh , S. Jehangir , R. Raut","doi":"10.1016/j.nuclphysa.2025.123019","DOIUrl":"10.1016/j.nuclphysa.2025.123019","url":null,"abstract":"<div><div>Two previously known bands in the excitation scheme of the <sup>154</sup>Tb nucleus have been investigated for the multipolarity and the electric/magnetic nature of the intra- and inter-band transitions. The excited states of the nucleus were populated in an <em>α</em>-beam induced reaction and the <em>γ</em>-rays emitted therefrom were detected using an array of Compton suppressed HPGe clover detectors. The experimental findings are indicative of a shape evolution of the nucleus and development of strong triaxiality at higher spins. The multipolarities of the inter-band transitions brings forth the same. Total Routhian Surface (TRS) calculations and those in the framework of Triaxial Projected Shell Model (TPSM) have been carried out and the results corroborate the proposition on triaxiality.</div></div>","PeriodicalId":19246,"journal":{"name":"Nuclear Physics A","volume":"1055 ","pages":"Article 123019"},"PeriodicalIF":1.7,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143153591","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}
Pub Date : 2025-01-13DOI: 10.1016/j.nuclphysa.2025.123018
Cheryl Henkels , Emmanuel G. de Oliveira , Roman Pasechnik , Haimon Trebien
We study the coherent photoproduction of light vector mesons in Pb-Pb collisions in the framework of color dipole approach. We employ the Glauber–Gribov formalism supplemented by an effective suppression factor accounting for the gluon shadowing correction. We adjust the latter to reproduce the deep inelastic structure function (E665) and ρ meson photoproduction (ALICE) data. We achieve a good description of the available data points with at scale GeV2. In addition, employing this suppression factor, we present predictions for coherent , and photoproduction observables using the holographic vector meson wave functions.
{"title":"Coherent photoproduction of light vector mesons off nuclear targets in the dipole picture","authors":"Cheryl Henkels , Emmanuel G. de Oliveira , Roman Pasechnik , Haimon Trebien","doi":"10.1016/j.nuclphysa.2025.123018","DOIUrl":"10.1016/j.nuclphysa.2025.123018","url":null,"abstract":"<div><div>We study the coherent photoproduction of light vector mesons in Pb-Pb collisions in the framework of color dipole approach. We employ the Glauber–Gribov formalism supplemented by an effective suppression factor <span><math><msub><mrow><mi>R</mi></mrow><mrow><mi>G</mi></mrow></msub></math></span> accounting for the gluon shadowing correction. We adjust the latter to reproduce the deep inelastic structure function <span><math><msub><mrow><mi>F</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span> (E665) and <em>ρ</em> meson photoproduction (ALICE) data. We achieve a good description of the available data points with <span><math><msub><mrow><mi>R</mi></mrow><mrow><mi>G</mi></mrow></msub><mo>=</mo><mn>0.85</mn></math></span> at scale <span><math><msubsup><mrow><mi>M</mi></mrow><mrow><mi>ρ</mi></mrow><mrow><mn>2</mn></mrow></msubsup><mo>/</mo><mn>4</mn><mo>=</mo><mn>0.15</mn></math></span> GeV<sup>2</sup>. In addition, employing this suppression factor, we present predictions for coherent <span><math><mi>ρ</mi><mo>(</mo><mn>2</mn><mi>S</mi><mo>)</mo></math></span>, <span><math><mi>ω</mi><mo>(</mo><mn>1</mn><mi>S</mi><mo>,</mo><mn>2</mn><mi>S</mi><mo>)</mo></math></span> and <span><math><mi>ϕ</mi><mo>(</mo><mn>1</mn><mi>S</mi><mo>,</mo><mn>2</mn><mi>S</mi><mo>)</mo></math></span> photoproduction observables using the holographic vector meson wave functions.</div></div>","PeriodicalId":19246,"journal":{"name":"Nuclear Physics A","volume":"1055 ","pages":"Article 123018"},"PeriodicalIF":1.7,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143153614","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}
Pub Date : 2025-01-09DOI: 10.1016/j.nuclphysa.2025.123017
Dalip Singh Verma, Pooja Chauhan, Vivek
The transition from asymmetric to symmetric fission in the 180Hg⁎ nucleus, formed in the 36Ar + 144Sm reaction, as a function of excitation energy and angular momentum has been investigated. Using the dynamical cluster-decay model, the fragmentation potential, preformation probability, and cross-sections have been analyzed for asymmetric (80, 100) and symmetric (90, 90) mass fission channels, considering both the optimum hot and cold orientations of the fragments, as well as the case of symmetric mass fission channel with fragments assumed to be spherical. The calculations reveal that deformed proton and neutron shell closures favour asymmetric fission at lower excitation energies, while a transition to symmetric fission occurs near 40 MeV of excitation energy due to changes in fragment deformation with excitation energy. These findings are consistent with the available experimental observations and theoretical predictions. The transition also occurs with increasing angular momentum, but only for optimum hot orientations.
{"title":"Asymmetric to symmetric fission transition in 180Hg⁎: Effects of excitation energy and angular momentum","authors":"Dalip Singh Verma, Pooja Chauhan, Vivek","doi":"10.1016/j.nuclphysa.2025.123017","DOIUrl":"10.1016/j.nuclphysa.2025.123017","url":null,"abstract":"<div><div>The transition from asymmetric to symmetric fission in the <sup>180</sup>Hg<sup>⁎</sup> nucleus, formed in the <sup>36</sup>Ar + <sup>144</sup>Sm reaction, as a function of excitation energy and angular momentum has been investigated. Using the dynamical cluster-decay model, the fragmentation potential, preformation probability, and cross-sections have been analyzed for asymmetric (80, 100) and symmetric (90, 90) mass fission channels, considering both the optimum hot and cold orientations of the fragments, as well as the case of symmetric mass fission channel with fragments assumed to be spherical. The calculations reveal that deformed proton and neutron shell closures favour asymmetric fission at lower excitation energies, while a transition to symmetric fission occurs near 40 MeV of excitation energy due to changes in fragment deformation with excitation energy. These findings are consistent with the available experimental observations and theoretical predictions. The transition also occurs with increasing angular momentum, but only for optimum hot orientations.</div></div>","PeriodicalId":19246,"journal":{"name":"Nuclear Physics A","volume":"1055 ","pages":"Article 123017"},"PeriodicalIF":1.7,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143154198","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}
Pub Date : 2025-01-08DOI: 10.1016/j.nuclphysa.2024.123011
Hadi Sobhani, Yan-An Luo
This paper investigates one of the most prominent models in nuclear physics, the Tamm-Dancoff approximation (TDA), for particle-hole excitations. We demonstrate how to incorporate one of the most challenging aspects of nuclear physics, the hardcore, into this model. Following an introduction to the concept and the corresponding mathematical tools, we examine the sample nuclei 16O and 40Ca. A portion of the excitation spectra of these nuclei is reproduced, and the octupole transition in these nuclei along with the TDA sum rule is investigated. The results are calculated and compared in both the well-known version and the new approach. In all cases, the new model exhibits better agreement with experimental data than the well-known model, which employed the harmonic oscillator basis.
{"title":"Implementing the hardcore concept in the mean field of the Tamm-Dancoff approximation","authors":"Hadi Sobhani, Yan-An Luo","doi":"10.1016/j.nuclphysa.2024.123011","DOIUrl":"10.1016/j.nuclphysa.2024.123011","url":null,"abstract":"<div><div>This paper investigates one of the most prominent models in nuclear physics, the Tamm-Dancoff approximation (TDA), for particle-hole excitations. We demonstrate how to incorporate one of the most challenging aspects of nuclear physics, the hardcore, into this model. Following an introduction to the concept and the corresponding mathematical tools, we examine the sample nuclei <sup>16</sup>O and <sup>40</sup>Ca. A portion of the excitation spectra of these nuclei is reproduced, and the octupole transition in these nuclei along with the TDA sum rule is investigated. The results are calculated and compared in both the well-known version and the new approach. In all cases, the new model exhibits better agreement with experimental data than the well-known model, which employed the harmonic oscillator basis.</div></div>","PeriodicalId":19246,"journal":{"name":"Nuclear Physics A","volume":"1055 ","pages":"Article 123011"},"PeriodicalIF":1.7,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143153569","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}
Pub Date : 2025-01-08DOI: 10.1016/j.nuclphysa.2025.123016
Pooja Chauhan , S. Sihotra , Renu Joshi , Dalip Singh Verma , R.P. Singh , R. Palit , D. Mehta
The study of possibility of antimagnetic rotation in 100Ru is studied on the basis of semiclassical particle-rotor model (SCM). In the high spin range 18+ to 28+, the dynamic moment of inertia falls within the typical range of antimagnetic rotation. The decrease in calculated transition probability B(E2) values with an increase in spin, and a sharp increase in the ratio of observed and calculated B(E2) values with spin shows the possible antimagnetic rotation character. Additionally, the calculated spin (ħ) versus frequency (MeV) plot of configuration ⊗ , which is comparable with experimental values supports the possibility of the AMR phenomenon in the positive parity band of 100Ru.
{"title":"Study of possible antimagnetic rotation in 100Ru","authors":"Pooja Chauhan , S. Sihotra , Renu Joshi , Dalip Singh Verma , R.P. Singh , R. Palit , D. Mehta","doi":"10.1016/j.nuclphysa.2025.123016","DOIUrl":"10.1016/j.nuclphysa.2025.123016","url":null,"abstract":"<div><div>The study of possibility of antimagnetic rotation in <sup>100</sup>Ru is studied on the basis of semiclassical particle-rotor model (SCM). In the high spin range 18<sup>+</sup> to 28<sup>+</sup>, the dynamic moment of inertia <span><math><msup><mrow><mo>ℑ</mo></mrow><mrow><mo>(</mo><mn>2</mn><mo>)</mo></mrow></msup></math></span> falls within the typical range of antimagnetic rotation. The decrease in calculated transition probability B(E2) values with an increase in spin, and a sharp increase in the ratio of observed <span><math><msup><mrow><mo>ℑ</mo></mrow><mrow><mo>(</mo><mn>2</mn><mo>)</mo></mrow></msup></math></span> and calculated B(E2) values with spin shows the possible antimagnetic rotation character. Additionally, the calculated spin (<em>ħ</em>) versus frequency (MeV) plot of configuration <span><math><mi>π</mi><msup><mrow><mo>(</mo><msub><mrow><mi>g</mi></mrow><mrow><mn>9</mn><mo>/</mo><mn>2</mn></mrow></msub><mo>)</mo></mrow><mrow><mo>−</mo><mn>2</mn></mrow></msup></math></span> ⊗ <span><math><mi>ν</mi><mo>[</mo><msubsup><mrow><mi>h</mi></mrow><mrow><mn>11</mn><mo>/</mo><mn>2</mn></mrow><mrow><mn>2</mn></mrow></msubsup><mspace></mspace><msup><mrow><mo>(</mo><msub><mrow><mi>g</mi></mrow><mrow><mn>7</mn><mo>/</mo><mn>2</mn></mrow></msub><mo>)</mo></mrow><mrow><mn>2</mn></mrow></msup><mo>]</mo></math></span>, which is comparable with experimental values supports the possibility of the AMR phenomenon in the positive parity band of <sup>100</sup>Ru.</div></div>","PeriodicalId":19246,"journal":{"name":"Nuclear Physics A","volume":"1055 ","pages":"Article 123016"},"PeriodicalIF":1.7,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143153568","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}
Pub Date : 2025-01-07DOI: 10.1016/j.nuclphysa.2025.123015
A. Obaid, A.M. Khalaf, M. Kotb, H.A. Ghanem
In this article, we showed that even-even Dysprosium isotopic chain follows a specific trajectory of evolution that appear to be from U(5) to near O(6) vertex inside the symmetry triangle. The analysis was done using the Extended Consistent Q formalism (ECQF) of the interacting boson model, and catastrophe theory. We determined the Hamiltonian parameters using the method of orthogonal crossing contours for key observables. The Potential Energy Surfaces (PES's) for each isotope was also obtained using the intrinsic coherent state formalism. The path of evolution for the chain showed the same trend-line in both the symmetry triangle and the separatrix plane of catastrophe theory. We also showed that despite being located near the O(6) limit in the symmetry triangle, neutron-rich Dy isotopes still exhibit the behaviour of good axially symmetric rotors but with a reduced gamma rigidity, and this apparent location is due to the non linearity of scales for observables inside the symmetry triangle.
{"title":"The apparent U(5) to near O(6) shape evolution in even-even 152→162Dy inside the symmetry triangle","authors":"A. Obaid, A.M. Khalaf, M. Kotb, H.A. Ghanem","doi":"10.1016/j.nuclphysa.2025.123015","DOIUrl":"10.1016/j.nuclphysa.2025.123015","url":null,"abstract":"<div><div>In this article, we showed that even-even <span><math><mi>A</mi><mo>=</mo><mn>152</mn><mo>⟶</mo><mn>162</mn></math></span> Dysprosium isotopic chain follows a specific trajectory of evolution that appear to be from U(5) to near O(6) vertex inside the symmetry triangle. The analysis was done using the Extended Consistent Q formalism (ECQF) of the interacting boson model, and catastrophe theory. We determined the Hamiltonian parameters using the method of orthogonal crossing contours for key observables. The Potential Energy Surfaces (PES's) for each isotope was also obtained using the intrinsic coherent state formalism. The path of evolution for the chain showed the same trend-line in both the symmetry triangle and the separatrix plane of catastrophe theory. We also showed that despite being located near the O(6) limit in the symmetry triangle, neutron-rich Dy isotopes still exhibit the behaviour of good axially symmetric rotors but with a reduced gamma rigidity, and this apparent location is due to the non linearity of scales for observables inside the symmetry triangle.</div></div>","PeriodicalId":19246,"journal":{"name":"Nuclear Physics A","volume":"1055 ","pages":"Article 123015"},"PeriodicalIF":1.7,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143153590","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}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号