Solar Physics最新文献

Direct Measurement of the Longitudinal Magnetic Field in the Solar Photosphere with the Zeeman Effect

IF 2.7 3区物理与天体物理

Solar Physics Pub Date : 2025-04-04 DOI: 10.1007/s11207-025-02455-7

Jie Chen, Jiangtao Su, Wenbin Xie, Yuanyong Deng, Xianyong Bai, Ziyao Hu, Haiqing Xu, Suo Liu, Yin Zhang, Yingzi Sun, Yongliang Song, Xiaofan Wang

引用次数: 0

On Field Line Slippage Rates in the Solar Corona

IF 2.7 3区物理与天体物理

Solar Physics Pub Date : 2025-04-04 DOI: 10.1007/s11207-025-02462-8

David MacTaggart

{"title":"On Field Line Slippage Rates in the Solar Corona","authors":"David MacTaggart","doi":"10.1007/s11207-025-02462-8","DOIUrl":"10.1007/s11207-025-02462-8","url":null,"abstract":"<div><p>Magnetic reconnection is one of the fundamental dynamical processes in the solar corona. The method of studying reconnection in active region-scale magnetic fields generally depends on <i>non-local</i> methods (i.e. requiring information across the magnetic field under study) of magnetic topology, such as separatrix skeletons and quasi-separatrix layers. The theory of General Magnetic Reconnection is also non-local, in that its measure of the reconnection rate depends on determining the maxima of integrals along field lines. In this work, we complement the above approaches by introducing a <i>local</i> description of magnetic reconnection, that is one in which information about reconnection at a particular location depends only on quantities at that location. This description connects the concept of the <i>field line slippage rate</i>, relative to ideal motion, to the underlying local geometry of the magnetic field characterized in terms of the Lorentz force and field-aligned current density. It is argued that the dominant non-ideal term for the solar corona, discussed in relation to this new description, is mathematically equivalent to the anomalous resistivity employed by many magnetohydrodynamic simulations. However, the general application of this new approach is adaptable to the inclusion of other non-ideal terms, which may arise from turbulence modelling or the inclusion of a generalized Ohm’s law. The approach is illustrated with two examples of coronal magnetic fields related to flux ropes: an analytical model and a nonlinear force-free extrapolation. In terms of the latter, the slippage rate corresponds to the reconnection that would happen if the given (static) force-free equilibrium were the instantaneous form of the magnetic field governed by an Ohm’s law with non-ideal terms.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"300 4","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11207-025-02462-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143778066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

引用次数: 0

Improved Tomographic Reconstruction of 3D Global Coronal Density from STEREO/COR1 Observations

IF 2.7 3区物理与天体物理

Solar Physics Pub Date : 2025-04-03 DOI: 10.1007/s11207-025-02454-8

Tongjiang Wang, C. Nick Arge, Shaela I. Jones

{"title":"Improved Tomographic Reconstruction of 3D Global Coronal Density from STEREO/COR1 Observations","authors":"Tongjiang Wang, C. Nick Arge, Shaela I. Jones","doi":"10.1007/s11207-025-02454-8","DOIUrl":"10.1007/s11207-025-02454-8","url":null,"abstract":"<div><p>Tomography is a powerful technique for recovering the three-dimensional (3D) density structure of the global solar corona. In this work, we present an improved tomography method by introducing radial weighting in the regularization term. Radial weighting provides balanced smoothing of density values across different heights, helping to recover finer structures at lower heights while also stabilizing the solution and preventing oscillatory artifacts at higher altitudes. We apply this technique to reconstruct the 3D electron density of Carrington Rotation (CR) 2098 using two weeks of polarized brightness (pB) observations from the inner coronagraph (COR1) on board spacecraft-B of the twin Solar Terrestrial Relations Observatory (STEREO), where the radial weighting function is taken as the inverse intensity background, calculated by averaging all the pB images used. Comparisons between density distributions at various heights from the tomography and magnetohydrodynamics (MHD) simulations show good agreement. We find that radial weighting not only effectively corrects the oversmoothing effect near the inner boundary in reconstructions using second-order smoothing but also significantly improves reconstruction quality when using zero-order smoothing. Additionally, comparing reconstructions for CR 2091 from single-satellite data with that from multiviewpoint data suggests that coronal evolution and dynamics may significantly impact on the reconstructed density structures. This improved tomography method has been used to create a database of 3D densities for CRs 2052 to 2154, based on STEREO/COR1-B data, covering the period from 08 January 2007 to 17 September 2014.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"300 4","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Turbulence Evolution Between 0.5 and 1 AU for the Solar Wind of Various Origins

IF 2.7 3区物理与天体物理

Solar Physics Pub Date : 2025-04-03 DOI: 10.1007/s11207-025-02458-4

Liudmila Rakhmanova, Maria Riazantseva, Yuri Yermolaev, Alexander Khokhlachev, Georgy Zastenker

引用次数: 0

A Study on the Transition-Range Spectral Index of the Solar Wind Turbulence in the Inner Heliosphere 内日光层太阳风湍流的过渡范围光谱指数研究

IF 2.7 3区物理与天体物理

Solar Physics Pub Date : 2025-04-03 DOI: 10.1007/s11207-025-02439-7

Haifeng Yang, Guoqing Zhao, Hengqiang Feng, Liang Xiang

{"title":"A Study on the Transition-Range Spectral Index of the Solar Wind Turbulence in the Inner Heliosphere","authors":"Haifeng Yang, Guoqing Zhao, Hengqiang Feng, Liang Xiang","doi":"10.1007/s11207-025-02439-7","DOIUrl":"10.1007/s11207-025-02439-7","url":null,"abstract":"<div><p>Based on observations from Parker Solar Probe, this paper studies the dependence of the correlations between the transition-range spectral index of the magnetic energy spectrum and four parameters (inertial-range cross-helicity and magnetic energy density, transition-range magnetic helicity, and bulk proton temperature) on solar wind speed and heliocentric distance. Results show significant correlations between the spectral index and both cross-helicity and magnetic energy density. Notably, at lower speeds or closer distances, the correlation coefficient (CC) between the cross-helicity and spectral index is smaller than that between the magnetic energy density and spectral index. Conversely, at higher speeds or greater distances, the correlation with cross-helicity becomes comparable to or even exceeds that with magnetic energy density. Additionally, as the speed increases or the heliocentric distance decreases, cross-helicity, magnetic energy density, proton temperature, and the absolute values of the spectral index show a mostly upward trend. Moreover, cross-helicity, absolute values of the spectral index, and CC between the magnetic energy density and spectral index exhibit a similar trend with the speed, initially rising and then declining at the highest speed bin. We discuss the results using the recently proposed “helicity barrier” effect.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"300 4","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Coronal Electric Currents and Kink Instability of Magnetic Flux Rope

IF 2.7 3区物理与天体物理

Solar Physics Pub Date : 2025-04-03 DOI: 10.1007/s11207-025-02461-9

Yuriy T. Tsap, Alexander V. Stepanov, Yulia G. Kopylova

{"title":"Coronal Electric Currents and Kink Instability of Magnetic Flux Rope","authors":"Yuriy T. Tsap, Alexander V. Stepanov, Yulia G. Kopylova","doi":"10.1007/s11207-025-02461-9","DOIUrl":"10.1007/s11207-025-02461-9","url":null,"abstract":"<div><p>Using the energy method and the thin magnetic flux tube approximation, we find the wave dispersion relation for magnetohydrodynamic kink oscillations of a force-free magnetic flux rope with uncompensated longitudinal electric current under solar coronal conditions. The eigenvectors are shown to impose restrictions on the conditions of the kink instability of a flux rope. The observed weak twist of coronal loops with a small (<span>(lesssim 1)</span>) number of turns of the magnetic field lines around the axis indicates the dominance of unshielded magnetic flux ropes in the corona of the Sun, in which the longitudinal electric currents do not exceed <span>(10^{11})</span> – <span>(10^{12})</span> A. These restrictions can be associated with the absence of solar superflares. The period of kink oscillations of twisted coronal loops should decrease with decreasing longitudinal electric current, which can be used to study its dynamics in solar flares. No dependence of compact and eruptive solar flares on the twist of flux ropes can be explained by the coexistence of both shielded and unshielded electric currents in the corona.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"300 4","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Turbulent Power: A Discriminator Between Sheaths and CMEs

IF 2.7 3区物理与天体物理

Solar Physics Pub Date : 2025-04-03 DOI: 10.1007/s11207-025-02457-5

Deep Ghuge, Debesh Bhattacharjee, Prasad Subramanian

引用次数: 0

Investigating Solar Wind Outflows from Open–Closed Magnetic Field Structures Using Coordinated Solar Orbiter and Hinode Observations

IF 2.7 3区物理与天体物理

Solar Physics Pub Date : 2025-04-03 DOI: 10.1007/s11207-025-02438-8

Nawin Ngampoopun, Roberto Susino, David H. Brooks, Roberto Lionello, Lucia Abbo, Daniele Spadaro, Deborah Baker, Lucie M. Green, David M. Long, Stephanie L. Yardley, Alexander W. James, Marco Romoli, Silvio M. Giordano, Aleksandr Burtovoi, Federico Landini, Giuliana Russano

{"title":"Investigating Solar Wind Outflows from Open–Closed Magnetic Field Structures Using Coordinated Solar Orbiter and Hinode Observations","authors":"Nawin Ngampoopun, Roberto Susino, David H. Brooks, Roberto Lionello, Lucia Abbo, Daniele Spadaro, Deborah Baker, Lucie M. Green, David M. Long, Stephanie L. Yardley, Alexander W. James, Marco Romoli, Silvio M. Giordano, Aleksandr Burtovoi, Federico Landini, Giuliana Russano","doi":"10.1007/s11207-025-02438-8","DOIUrl":"10.1007/s11207-025-02438-8","url":null,"abstract":"<div><p>ESA/NASA’s Solar Orbiter (SO) enables us to study the solar corona at closer distances and from different perspectives, which helps us to gain significant insights into the origin of the solar wind. In this work, we present the analysis of solar wind outflows from two locations: a narrow open-field corridor and a small, mid-latitude coronal hole. These outflows were observed off-limb by the Metis coronagraph onboard SO and on-disk by the Extreme Ultraviolet Imaging Spectrometer (EIS) onboard Hinode. Magnetic field extrapolations suggest that the upflow regions seen in EIS were the sources of the outflowing solar wind observed with Metis. We find that the plasma associated with the narrow open-field corridor has higher electron densities and lower outflow velocities compared to the coronal hole plasma in the middle corona, even though the plasma properties of the two source regions in the low corona are found to be relatively similar. The speed of the solar wind from the open-field corridor also shows no correlation with the magnetic field expansion factor, unlike the coronal hole. These pronounced differences at higher altitudes may arise from the dynamic nature of the low-middle corona, in which reconnection can readily occur and may play an important role in driving solar wind variability.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"300 4","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11207-025-02438-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

引用次数: 0

Transverse Oscillations in Thin Magnetic Tubes with Elliptical Cross-Sections: The Effect of Field Aligned Flow

IF 2.7 3区物理与天体物理

Solar Physics Pub Date : 2025-04-02 DOI: 10.1007/s11207-025-02460-w

Igor Lopin

{"title":"Transverse Oscillations in Thin Magnetic Tubes with Elliptical Cross-Sections: The Effect of Field Aligned Flow","authors":"Igor Lopin","doi":"10.1007/s11207-025-02460-w","DOIUrl":"10.1007/s11207-025-02460-w","url":null,"abstract":"<div><p>The effect of longitudinal plasma flow on transverse oscillations in the thin magnetic tubes with elliptical cross-sections is examined. The backward propagating waves of the <span>(M)</span>-kink mode (polarized along the major axis) and <span>(m)</span>-kink mode (polarized along the minor axis) are found to reverse their propagation direction at certain flow thresholds. The critical flow for the <span>(M)</span>-kink mode is lower than in a circular tube and is close to the internal Alfvén speed. This result is of particular interest within the concept of existence of negative energy waves in solar waveguides. Both modes are subjected to the Kelvin–Helmholtz (KH) instability, and the <span>(M)</span>-mode is more stable than the <span>(m)</span>-mode. Magnetic tubes with significant ellipticity are more resistant to the KH instability than circular tubes. In the quasi-standing wave regime, the frequencies of both modes decrease and the frequency ratio <span>(omega _{m}/omega _{M})</span> increases with faster flows. The obtained results are used to interpret the observed transverse oscillations of the solar limb spicules and their helical motions in terms of the <span>(M)</span>- and <span>(m)</span>-kink modes.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"300 4","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

A New Implementation of a Fourth-Order CESE Scheme for 3D MHD Simulations

IF 2.7 3区物理与天体物理

Solar Physics Pub Date : 2025-03-28 DOI: 10.1007/s11207-025-02452-w

Chaowei Jiang, Ling Zhang

{"title":"A New Implementation of a Fourth-Order CESE Scheme for 3D MHD Simulations","authors":"Chaowei Jiang, Ling Zhang","doi":"10.1007/s11207-025-02452-w","DOIUrl":"10.1007/s11207-025-02452-w","url":null,"abstract":"<div><p>This paper is devoted to the description and validation of a new implementation of a fourth-order space–time conservation-element and solution-element (CESE) scheme to numerically solve the time-dependent, three-dimensional (3D) magnetohydrodynamic (MHD) equations. The core of the scheme is that, with the aid of a grid staggered in space and time, the conservative variables are advanced by integration of the controlling equation in the space–time four-dimensional domain by utilizing Taylor expansion, and their spatial derivatives are computed by finite difference with <span>(p)</span> order derivatives from <span>(p-1)</span> order ones. The new scheme achieves fourth-order accuracy in both space and time simultaneously, using a compact stencil identical to that in the second-order CESE scheme. We provide a general framework for convenience of programming such that the scheme can be easily extended to arbitrarily higher order by including higher-order terms in the Taylor series. A suite of 3D MHD tests demonstrate that the fourth-order CESE scheme at relatively low grid resolutions can obtain reliable solution comparable to the second-order CESE scheme at four-times higher resolution, and showing a very high efficiency in computing by using only around <span>(5%)</span> of the computing resources.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"300 4","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143716806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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