Pub Date : 2024-10-21DOI: 10.1140/epjd/s10053-024-00915-6
Peter R. Young
The Sun is a standard reference object for astrophysics and also a fascinating subject of study in its own right. X-ray and extreme ultraviolet movies of the Sun’s atmosphere show an extraordinary diversity of plasma phenomena, from barely visible bursts and jets to coronal mass ejections that impact a large portion of the solar surface. The processes that produce these phenomena, heat the corona and power the solar wind remain actively studied and accurate atomic data are essential for interpreting observations and making model predictions. For the Sun’s interior intense effort is focused on resolving the “solar problem,” (a discrepancy between solar interior models and helioseismology measurements) and atomic data are central to both element abundance measurements and interior physics such as opacity and nuclear reaction rates. In this article, topics within solar interior and solar atmosphere physics are discussed and the role of atomic data described. Areas of active research are highlighted and specific atomic data needs are identified.
An image of a solar active region obtained with the 193 A channel of SDO/AIA, showing plasma at around 1.5 million degrees.
太阳是天体物理学的标准参照物,其本身也是一个引人入胜的研究课题。太阳大气层的 X 射线和极紫外线电影显示了非同寻常的多种等离子体现象,从几乎看不见的爆发和喷流到影响大部分太阳表面的日冕物质抛射。产生这些现象、加热日冕和为太阳风提供动力的过程仍在积极研究之中,准确的原子数据对于解释观测结果和进行模型预测至关重要。对于太阳内部,人们正集中精力解决 "太阳问题"(太阳内部模型与日震学测量之间的差异),而原子数据对于元素丰度测量和内部物理学(如不透明度和核反应速率)都至关重要。本文讨论了太阳内部物理学和太阳大气物理学的主题,并介绍了原子数据的作用。文章强调了积极研究的领域,并确定了具体的原子数据需求。
{"title":"Applications of atomic data to studies of the Sun","authors":"Peter R. Young","doi":"10.1140/epjd/s10053-024-00915-6","DOIUrl":"10.1140/epjd/s10053-024-00915-6","url":null,"abstract":"<p>The Sun is a standard reference object for astrophysics and also a fascinating subject of study in its own right. X-ray and extreme ultraviolet movies of the Sun’s atmosphere show an extraordinary diversity of plasma phenomena, from barely visible bursts and jets to coronal mass ejections that impact a large portion of the solar surface. The processes that produce these phenomena, heat the corona and power the solar wind remain actively studied and accurate atomic data are essential for interpreting observations and making model predictions. For the Sun’s interior intense effort is focused on resolving the “solar problem,” (a discrepancy between solar interior models and helioseismology measurements) and atomic data are central to both element abundance measurements and interior physics such as opacity and nuclear reaction rates. In this article, topics within solar interior and solar atmosphere physics are discussed and the role of atomic data described. Areas of active research are highlighted and specific atomic data needs are identified.</p><p>An image of a solar active region obtained with the 193 A channel of SDO/AIA, showing plasma at around 1.5 million degrees.</p>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjd/s10053-024-00915-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142453113","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}
The interaction between ion beams and plasma is a fundamental and important physical process, plasma can effectively neutralize the current and charge of ion beam pulses as an ideal medium for its transmission and focusing. The analytical model of short heavy ion beam pulse in cold background plasma under external magnetic field is established. Combined with the experimental parameters, by 2.5D particle-in-cell numerical simulations, the entire transport process of heavy ion beam application strong magnetic fields in plasma is investigated. Our research results indicate that the interaction between short-pulse heavy ion beams and plasma generates a longitudinally induced magnetic field in the same direction as the external magnetic field. Moreover, the electron cyclotron electromagnetic waves of anti-parallel to local magnetic field are excited, and the excitation mechanism is mainly drift instability of electrons beam caused by the heavy ion beam.
Temporal variations of the longitudinal induced magnetic field Bz in plasma and vacuum regions under different external magnetic fields
{"title":"Enhancement of longitudinal magnetic field by interaction of heavy ion beams and plasma with strong magnetic field","authors":"Heng Zhang, Fei-Fei Li, Fang-Ping Wang, Wen-Shan Duan, Sheng Zhang, Liang-Wen Chen","doi":"10.1140/epjd/s10053-024-00922-7","DOIUrl":"10.1140/epjd/s10053-024-00922-7","url":null,"abstract":"<p>The interaction between ion beams and plasma is a fundamental and important physical process, plasma can effectively neutralize the current and charge of ion beam pulses as an ideal medium for its transmission and focusing. The analytical model of short heavy ion beam pulse in cold background plasma under external magnetic field is established. Combined with the experimental parameters, by 2.5D particle-in-cell numerical simulations, the entire transport process of heavy ion beam application strong magnetic fields in plasma is investigated. Our research results indicate that the interaction between short-pulse heavy ion beams and plasma generates a longitudinally induced magnetic field in the same direction as the external magnetic field. Moreover, the electron cyclotron electromagnetic waves of anti-parallel to local magnetic field are excited, and the excitation mechanism is mainly drift instability of electrons beam caused by the heavy ion beam.</p><p>Temporal variations of the longitudinal induced magnetic field Bz in plasma and vacuum regions under different external magnetic fields</p>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142453114","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 : 2024-10-21DOI: 10.1140/epjd/s10053-024-00921-8
Zhuang-Zhuang Meng, Lei Liu, Lei Tan
We propose an dimer model consisting of two coupled microwave cavities with each cavity containing a two-level atom and a YIG sphere placed in the biased magnetic field. We use the semiclassical approximation and quantum master equation to investigate the delocalization–localization transition of the system. We find the sharp transition and the great photon localization under lower excitation. We also find that increasing initial photon number and magnon excitation can facilitate the localization. We also investigate the local second-order photon correlations to reflect the localization. The work suggests a new platform for studying the delocalization–localization transition of photons in cavity optomagnonic systems, with potential applications in quantum information processing. The article also discusses the experimental relevance of the model parameters.
{"title":"Non-equilibrium delocalization–localization transition of photons in two coupled microwave cavities","authors":"Zhuang-Zhuang Meng, Lei Liu, Lei Tan","doi":"10.1140/epjd/s10053-024-00921-8","DOIUrl":"10.1140/epjd/s10053-024-00921-8","url":null,"abstract":"<div><p>We propose an dimer model consisting of two coupled microwave cavities with each cavity containing a two-level atom and a YIG sphere placed in the biased magnetic field. We use the semiclassical approximation and quantum master equation to investigate the delocalization–localization transition of the system. We find the sharp transition and the great photon localization under lower excitation. We also find that increasing initial photon number and magnon excitation can facilitate the localization. We also investigate the local second-order photon correlations to reflect the localization. The work suggests a new platform for studying the delocalization–localization transition of photons in cavity optomagnonic systems, with potential applications in quantum information processing. The article also discusses the experimental relevance of the model parameters.</p></div>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142453112","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 : 2024-10-19DOI: 10.1140/epjd/s10053-024-00924-5
S. Chintalwad, B. Ramakrishna, Lap Van Dao
We conducted a study on high-harmonic generation (HHG) in mixed gases, specifically Ar–Ne or Ar–Kr, with the aim of investigating the impact of ionization rate and neutral dispersion on the HHG process. Our focus was on understanding how these factors influence the HHG process when using gases with low and high ionization potentials. Based on phase-matched high-order harmonic generation in pure Ar gas, our investigation shows that the influence of plasma dispersion and neutral dispersion can be varied independently in mixed gas while the laser intensity is kept constant. Our results reveal that the addition of low ionization potential gases, such as Kr, to the Ar gas leads to a more rapid reduction in phase matching, due to the strong effects of ionization. The observed experimental outcomes align well with our theoretical calculations. This study provides valuable insights into the interplay of ionization rate and neutral dispersion in high-harmonic generation and the special requirement of the controlling of laser intensity for phase-matched harmonic generation. The findings contribute to a deeper understanding of the underlying dynamics and offer practical considerations for optimizing HHG properties.
{"title":"Investigating the influence of ionization on high-harmonic generation in Ar–Ne and Ar–Kr gas mixtures driven by kHz laser pulses","authors":"S. Chintalwad, B. Ramakrishna, Lap Van Dao","doi":"10.1140/epjd/s10053-024-00924-5","DOIUrl":"10.1140/epjd/s10053-024-00924-5","url":null,"abstract":"<div><p>We conducted a study on high-harmonic generation (HHG) in mixed gases, specifically Ar–Ne or Ar–Kr, with the aim of investigating the impact of ionization rate and neutral dispersion on the HHG process. Our focus was on understanding how these factors influence the HHG process when using gases with low and high ionization potentials. Based on phase-matched high-order harmonic generation in pure Ar gas, our investigation shows that the influence of plasma dispersion and neutral dispersion can be varied independently in mixed gas while the laser intensity is kept constant. Our results reveal that the addition of low ionization potential gases, such as Kr, to the Ar gas leads to a more rapid reduction in phase matching, due to the strong effects of ionization. The observed experimental outcomes align well with our theoretical calculations. This study provides valuable insights into the interplay of ionization rate and neutral dispersion in high-harmonic generation and the special requirement of the controlling of laser intensity for phase-matched harmonic generation. The findings contribute to a deeper understanding of the underlying dynamics and offer practical considerations for optimizing HHG properties.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142451073","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 : 2024-10-19DOI: 10.1140/epjd/s10053-024-00920-9
D. Agačević, N. Ibrišimović, D. Škrgić, D. B. Milošević
We investigate how the above-threshold ionization by an intense circularly polarized infrared laser pulse is modified in the presence of a strong circularly polarized terahertz pulse. It is shown that both the differential ionization probability and the maximum photoelectron kinetic energy can be increased or decreased by an order of magnitude by changing the time delay between the laser and terahertz pulses. The results obtained by numerical integration agree well with those obtained using the modified saddle-point method. The used laser and terahertz pulse parameters are readily available at the modern experimental facilities.
{"title":"Above-threshold ionization by a strong circularly polarized laser pulse assisted by a terahertz pulse","authors":"D. Agačević, N. Ibrišimović, D. Škrgić, D. B. Milošević","doi":"10.1140/epjd/s10053-024-00920-9","DOIUrl":"10.1140/epjd/s10053-024-00920-9","url":null,"abstract":"<p>We investigate how the above-threshold ionization by an intense circularly polarized infrared laser pulse is modified in the presence of a strong circularly polarized terahertz pulse. It is shown that both the differential ionization probability and the maximum photoelectron kinetic energy can be increased or decreased by an order of magnitude by changing the time delay between the laser and terahertz pulses. The results obtained by numerical integration agree well with those obtained using the modified saddle-point method. The used laser and terahertz pulse parameters are readily available at the modern experimental facilities.</p>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142451050","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 : 2024-10-18DOI: 10.1140/epjd/s10053-024-00918-3
Rabeet Singh, Arup Banerjee
In this article, we propose an alternate approach to study confined two-electron systems using the modified form of the Le Sech wavefunction. In the present approach, rather than using the cut-off factor in the variational wavefunction, we determine it directly by solving Schrödinger like equation. The results for kinetic energies, electron-nucleus interaction, electron–electron interaction, total energies, densities, ionization energies, and moments of confined (hbox {H}^-) and He atom are compared with the most accurate values found in the literature to show the effectiveness of our method. The present approach applies to a wide range of confinement potentials. We demonstrate it by showing the results for Coulomb, harmonic oscillator, and soft-confinement potentials.
在本文中,我们提出了另一种利用勒塞赫波函数的修正形式来研究约束双电子系统的方法。在本方法中,我们不使用变异波函数中的截止因子,而是直接通过求解薛定谔方程来确定截止因子。与文献中发现的最精确值相比,我们得出了约束(hbox {H}^-)和 He 原子的动能、电子-核相互作用、电子-电子相互作用、总能、密度、电离能和动量的结果,从而显示了我们方法的有效性。本方法适用于广泛的约束势。我们展示了库仑势、谐振子势和软约束势的结果。
{"title":"Modified Le Sech wavefunction for investigating confined two-electron atomic systems","authors":"Rabeet Singh, Arup Banerjee","doi":"10.1140/epjd/s10053-024-00918-3","DOIUrl":"10.1140/epjd/s10053-024-00918-3","url":null,"abstract":"<p>In this article, we propose an alternate approach to study confined two-electron systems using the modified form of the Le Sech wavefunction. In the present approach, rather than using the cut-off factor in the variational wavefunction, we determine it directly by solving Schrödinger like equation. The results for kinetic energies, electron-nucleus interaction, electron–electron interaction, total energies, densities, ionization energies, and moments of confined <span>(hbox {H}^-)</span> and He atom are compared with the most accurate values found in the literature to show the effectiveness of our method. The present approach applies to a wide range of confinement potentials. We demonstrate it by showing the results for Coulomb, harmonic oscillator, and soft-confinement potentials.</p>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142447320","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 : 2024-10-17DOI: 10.1140/epjd/s10053-024-00904-9
M. F. Rojas, M. A. Quinto, R. D. Rivarola, J. M. Monti
In the present work, we address the problem of single ionisation in ion molecule collisions by implementing the dynamic charge continuum distorted wave—eikonal initial state model. A dynamic charge that depends simultaneously on both the emission angle and the emission energy is used to approximate the non-Coulomb potential of the residual molecular target. The molecular ground state is described employing a complete neglected of differential overlap approximation. The results in terms of total, single, and doubly differential cross sections are calculated and compared with available experimental data. Also, the contribution of each molecular orbital to the total cross section has been considered.
{"title":"Dynamic effective charge in the continuum final state in the CDW-EIS model: ionisation of molecules by bare-ion impact","authors":"M. F. Rojas, M. A. Quinto, R. D. Rivarola, J. M. Monti","doi":"10.1140/epjd/s10053-024-00904-9","DOIUrl":"10.1140/epjd/s10053-024-00904-9","url":null,"abstract":"<p>In the present work, we address the problem of single ionisation in ion molecule collisions by implementing the dynamic charge continuum distorted wave—eikonal initial state model. A dynamic charge that depends simultaneously on both the emission angle and the emission energy is used to approximate the non-Coulomb potential of the residual molecular target. The molecular ground state is described employing a complete neglected of differential overlap approximation. The results in terms of total, single, and doubly differential cross sections are calculated and compared with available experimental data. Also, the contribution of each molecular orbital to the total cross section has been considered.\u0000</p>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142447361","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 : 2024-10-15DOI: 10.1140/epjd/s10053-024-00917-4
Giorgio Turri, Paola Bolognesi, Lorenzo Avaldi
The Triple-Differential Cross Section (TDCS) for the Photo Double-Ionization of carbon dioxide molecule to the CO22+ X3 Σg− ground state has been measured at 20 eV excess energy. In the experiment the coincidence angular distributions of the two photoelectrons, where the direction of one photoelectron has been fixed at 0, 30 and 60° with respect to the direction of the polarization of the incident radiation, have been measured for a condition where the two photoelectrons equally share the excess energy. Care has been taken to perform the measurements with an energy resolution which enabled to isolate the TDCS of the X3Σ−g ground state of the dication. An appreciable contribution to TDCS at a relative angle θ12 = 180° has been observed and attributed to a favorite symmetry of the wavefunction of the two ejected electrons.
Graphical abstract
TDCS of CO2 measures at photon energy 57.7eV, θ1=0, 30 and 60° and equal energy sharing of 10 eV are reported as black dots. Panels (a) and (c) report the TDCS as calculated by Alwan et al. (J Phys B: At Mol Opt Phys 48:185203, 2015) using the charge in the Sommerfeld parameters for the oxygen atom of 0.2 (black full curve) and 0.8 (ref full curve). The blue full curve in panels (d)-(f) is the fit to the experiments with the helium=like model by Reddsih and Feaging (J Phys B: At Mol Opt Phys 32:2473, 1999).
{"title":"Photo double-ionization of CO2 studied by photoelectron-photoelectron coincidence experiments at 20 eV excess energy in equal energy sharing conditions","authors":"Giorgio Turri, Paola Bolognesi, Lorenzo Avaldi","doi":"10.1140/epjd/s10053-024-00917-4","DOIUrl":"10.1140/epjd/s10053-024-00917-4","url":null,"abstract":"<div><p>The Triple-Differential Cross Section (TDCS) for the Photo Double-Ionization of carbon dioxide molecule to the CO<sub>2</sub><sup>2+</sup> X<sup>3</sup> Σ<sub>g</sub><sup>−</sup> ground state has been measured at 20 eV excess energy. In the experiment the coincidence angular distributions of the two photoelectrons, where the direction of one photoelectron has been fixed at 0, 30 and 60° with respect to the direction of the polarization of the incident radiation, have been measured for a condition where the two photoelectrons equally share the excess energy. Care has been taken to perform the measurements with an energy resolution which enabled to isolate the TDCS of the X<sup>3</sup>Σ<sup>−</sup><sub>g</sub> ground state of the dication. An appreciable contribution to TDCS at a relative angle θ<sub>12</sub> = 180° has been observed and attributed to a favorite symmetry of the wavefunction of the two ejected electrons.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div><p>TDCS of CO<sub>2</sub> measures at photon energy 57.7eV, θ<sub>1</sub>=0, 30 and 60° and equal energy sharing of 10 eV are reported as black dots. Panels (a) and (c) report the TDCS as calculated by Alwan et al. (J Phys B: At Mol Opt Phys 48:185203, 2015) using the charge in the Sommerfeld parameters for the oxygen atom of 0.2 (black full curve) and 0.8 (ref full curve). The blue full curve in panels (d)-(f) is the fit to the experiments with the helium=like model by Reddsih and Feaging (J Phys B: At Mol Opt Phys 32:2473, 1999).</p></div>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142434764","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 : 2024-10-12DOI: 10.1140/epjd/s10053-024-00919-2
E. M. Tari, S. Zahraoui, M. Ibnchaikh, N. Hachem
The Wentzel–Kramers–Brillouin approximation is applied to study the light scattering properties of an arbitrarily oriented cubic particle. The form factor and extinction coefficient of this particle are expressed in simple analytical expressions. The effects of certain physical parameters, namely angles of incidence, scattering azimuthal and zenith angles, refractive index and size parameter, on the form factor and extinction coefficient are analyzed. Some numerical examples are also presented to illustrate the results.
{"title":"Light scattering of an arbitrarily oriented cubic particle within the Wentzel–Kramers–Brillouin approach","authors":"E. M. Tari, S. Zahraoui, M. Ibnchaikh, N. Hachem","doi":"10.1140/epjd/s10053-024-00919-2","DOIUrl":"10.1140/epjd/s10053-024-00919-2","url":null,"abstract":"<p>The Wentzel–Kramers–Brillouin approximation is applied to study the light scattering properties of an arbitrarily oriented cubic particle. The form factor and extinction coefficient of this particle are expressed in simple analytical expressions. The effects of certain physical parameters, namely angles of incidence, scattering azimuthal and zenith angles, refractive index and size parameter, on the form factor and extinction coefficient are analyzed. Some numerical examples are also presented to illustrate the results.</p>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142411526","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 : 2024-10-01DOI: 10.1140/epjd/s10053-024-00914-7
Shu-Xing Wang, Carsten Brandau, Stephan Fritzsche, Sebastian Fuchs, Zoltán Harman, Christophor Kozhuharov, Alfred Müller, Markus Steck, Stefan Schippers
Electron-ion collision spectroscopy of the KLL dielectronic recombination (DR) resonances of hydrogenlike xenon ions was performed at a heavy-ion storage ring with a resolving power that is competitive with x-ray spectroscopy of inner-shell transitions in highly charged ions. The (KL_{1/2}L_{1/2}), (KL_{1/2}L_{3/2}), and (KL_{3/2}L_{3/2}) resonance groups and even parts of their fine structure are individually resolved. The resonance strengths were measured on an absolute scale and compared with results from multi-configuration Dirac–Fock (MCDF) calculations. These are in excellent agreement with the experimental findings when QED effects on the resonance energies and the Breit interaction are considered. As already found for DR of hydrogenlike uranium (Bernhardt et al. in Phys Rev A 83:020701(R), 2011), this interaction is particularly strong for the (KL_{1/2}L_{1/2}) resonance group. For U(^{91+}), it increases the (KL_{1/2}L_{1/2}) DR resonance strength by 40%. For Xe(^{53+}), the increase is found to amount to 25%, confirming the prediction that the influence of the Breit interaction grows with increasing nuclear charge. A comprehensive appendix treats the derivation of experimental and theoretical merged-beams recombination rate coefficients for interacting beams of relativistic electrons and ions.
在重离子存储环上对类氢氙离子的 KLL 介电重组(DR)共振进行了电子-离子碰撞光谱分析,其分辨能力可与高电荷离子内壳跃迁的 X 射线光谱分析相媲美。(KL_{1/2}L_{1/2})、(KL_{1/2}L_{3/2})和(KL_{3/2}L_{3/2})共振组甚至它们的部分精细结构都被单独解析出来。共振强度是在绝对尺度上测量的,并与多构型狄拉克-福克(MCDF)计算的结果进行了比较。当考虑到 QED 对共振能量的影响和 Breit 相互作用时,这些结果与实验结果非常吻合。正如在类氢铀的 DR 中已经发现的那样(Bernhardt 等人,Phys Rev A 83:020701(R), 2011),这种相互作用对于 (KL_{1/2}L_{1/2}) 共振组尤其强烈。对于铀(^{91+}),它使(KL_{1/2}L_{1/2}) DR共振强度增加了40%。对于 Xe(^{53+}) 来说,这种增加达到了 25%,证实了布雷特相互作用的影响随着核电荷的增加而增加的预测。一个全面的附录讨论了相对论电子和离子相互作用束的实验和理论合并束重组率系数的推导。
{"title":"Breit interaction in dielectronic recombination of hydrogenlike xenon ions: storage-ring experiment and theory","authors":"Shu-Xing Wang, Carsten Brandau, Stephan Fritzsche, Sebastian Fuchs, Zoltán Harman, Christophor Kozhuharov, Alfred Müller, Markus Steck, Stefan Schippers","doi":"10.1140/epjd/s10053-024-00914-7","DOIUrl":"10.1140/epjd/s10053-024-00914-7","url":null,"abstract":"<p>Electron-ion collision spectroscopy of the <i>KLL</i> dielectronic recombination (DR) resonances of hydrogenlike xenon ions was performed at a heavy-ion storage ring with a resolving power that is competitive with x-ray spectroscopy of inner-shell transitions in highly charged ions. The <span>(KL_{1/2}L_{1/2})</span>, <span>(KL_{1/2}L_{3/2})</span>, and <span>(KL_{3/2}L_{3/2})</span> resonance groups and even parts of their fine structure are individually resolved. The resonance strengths were measured on an absolute scale and compared with results from multi-configuration Dirac–Fock (MCDF) calculations. These are in excellent agreement with the experimental findings when QED effects on the resonance energies and the Breit interaction are considered. As already found for DR of hydrogenlike uranium (Bernhardt et al. in Phys Rev A 83:020701(R), 2011), this interaction is particularly strong for the <span>(KL_{1/2}L_{1/2})</span> resonance group. For U<span>(^{91+})</span>, it increases the <span>(KL_{1/2}L_{1/2})</span> DR resonance strength by 40%. For Xe<span>(^{53+})</span>, the increase is found to amount to 25%, confirming the prediction that the influence of the Breit interaction grows with increasing nuclear charge. A comprehensive appendix treats the derivation of experimental and theoretical merged-beams recombination rate coefficients for interacting beams of relativistic electrons and ions.</p>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjd/s10053-024-00914-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142409305","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}