Solar Physics最新文献

{"title":"HelioIndex: A Directory of Active Researchers in Solar and Heliospheric Physics","authors":"Peter R. Young","doi":"10.1007/s11207-025-02488-y","DOIUrl":"10.1007/s11207-025-02488-y","url":null,"abstract":"<div><p>HelioIndex is a directory of authors who are active in solar and heliospheric physics (SHP). It is available at the webpage HelioIndex.org, and it includes several derived products such as publication lists, country and institute data, journal data, and lists of the most cited articles in the field. HelioIndex is built from ORCID identifiers and publication data obtained from the Astrophysics Data System and ORCID. Selection criteria have been chosen to approximately correspond to a researcher having completed a PhD and published original research in a refereed journal. HelioIndex is intended to be a comprehensive directory of SHP authors that is generated and maintained through software procedures, with minimal human intervention. At the time of writing, 1910 SHP researchers are listed in HelioIndex and they belong to 55 countries. The countries with the largest numbers of researchers are the US, China and the UK, with 29%, 15%, and 8% of the total, respectively. HelioIndex authors average 0.69 first author papers per year over their careers, and the median citations for a paper is 15. Based on journal keyword data, it is estimated that 57% and 28% of HelioIndex authors belong to solar physics and heliospheric physics, respectively, with the remainder overlapping both disciplines.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"300 6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11207-025-02488-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145142096","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}

{"title":"Understanding the Ly(alpha ) Emission Observed by the Solar Disk Imager Aboard the Advanced Space-Based Solar Observatory","authors":"Yiliang Li,&nbsp;Ping Zhang,&nbsp;Zhengyuan Tian,&nbsp;Li Feng,&nbsp;Guanglu Shi,&nbsp;Jianchao Xue,&nbsp;Ying Li,&nbsp;Jun Tian,&nbsp;Kaifan Ji,&nbsp;Beili Ying,&nbsp;Lei Lu,&nbsp;Shuting Li,&nbsp;Jiahui Shan,&nbsp;Hui Li,&nbsp;Weiqun Gan","doi":"10.1007/s11207-025-02491-3","DOIUrl":"10.1007/s11207-025-02491-3","url":null,"abstract":"<div><p>The H <span>i</span> Lyman-alpha (Ly<span>(alpha )</span>) emission, with a wavelength of 1216 Å, is the brightest solar ultraviolet (UV) line. However, comprehensive observations of the Ly<span>(alpha )</span> emission line across the full solar disk remain limited. As part of the ASO-S mission, the Solar Disk Imager (SDI) has successfully captured full-disk images in the Ly<span>(alpha )</span> band. Gaussian fitting of SDI’s spectral response function (SRF) yields a full width at half maximum (FWHM) of approximately 85 Å, which is significantly broader than the distance of Si <span>iii</span> line at 1206 Å and the Ly<span>(alpha )</span> line. Thus, the emission contribution of Si <span>iii</span> to the SDI Ly<span>(alpha )</span> passband needs to be considered. For flares, in practice, we calculated the integrated intensity ratio <span>(I)</span>(Si <span>iii</span>)/<span>(I)</span>(Ly<span>(alpha )</span>) by analyzing spectral observations from the SOLSTICE instrument. It yields values between 1.7% and 14.6%. Empirically, the ratio is proportional to the SXR flux. Further analysis of spectral data from the SUMER instrument reveals that the ratio <span>(I)</span>(Si <span>iii</span>)/<span>(I)</span>(Ly<span>(alpha )</span>) is approximately 0.5% for prominences, 0.7% – 0.9% for the inner disk, and 1.4% – 1.9% close to the limb. These findings suggest that <span>(I)</span>(Si <span>iii</span>)/<span>(I)</span>(Ly<span>(alpha )</span>) is minimal for prominences and the inner disk, and the varying ratios across regions align with the center-to-limb variation of the Si <span>iii</span> and Ly<span>(alpha )</span> lines. Additionally, we compared Ly<span>(alpha )</span> image intensity with 304 Å, 1600 Å, and 1700 Å observations from AIA, as well as H<span>(alpha )</span> from CHASE, in multiple regions (a prominence region, two active regions, and a quiet region). A relatively higher correlation of about 85% is found between Ly<span>(alpha )</span> and 304 Å in active regions, whereas in the quiet region and prominence, their correlation coefficients are about 55%.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"300 6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145142005","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}

{"title":"On the Penumbra-to-Umbra Ratio from 1660 to 1676","authors":"Nadezhda Zolotova,&nbsp;Mikhail Vokhmyanin","doi":"10.1007/s11207-025-02489-x","DOIUrl":"10.1007/s11207-025-02489-x","url":null,"abstract":"<div><p>Sunspot engravings made in the Maunder minimum are used to evaluate the fine structure of sunspots. Based on 78 images of the full solar disk and 77 images of individual sunspots, we have evaluated the ratio of penumbra-to-umbra area (P/U) to be <span>(4.2 pm 2.5)</span> and <span>(3.8 pm 2.3)</span>, respectively. These results are consistent with previous estimates before, during, and after the Maunder minimum, as well as with the P/U ratio observed in the largest sunspot groups in Solar Cycle 24. This suggests that the near-surface convection mode has most likely remained unchanged since the early seventeenth century. We also found that schematic sunspot drawings tend to underestimate the P/U ratio.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"300 6","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145142256","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}

{"title":"The High-Energy Protons of the Ground Level Enhancement (GLE74) Event on 11 May 2024","authors":"A. Papaioannou,&nbsp;A. Mishev,&nbsp;I. Usoskin,&nbsp;B. Heber,&nbsp;R. Vainio,&nbsp;N. Larsen,&nbsp;M. Jarry,&nbsp;A. P. Rouillard,&nbsp;N. Talebpour Sheshvan,&nbsp;M. Laurenza,&nbsp;M. Dumbović,&nbsp;G. Vasalos,&nbsp;J. Gieseler,&nbsp;S. Koldobskiy,&nbsp;O. Raukunen,&nbsp;C. Palmroos,&nbsp;M. Hörlöck,&nbsp;M. Köberle,&nbsp;R. F. Wimmer-Schweingruber,&nbsp;A. Anastasiadis,&nbsp;P. Kühl,&nbsp;E. Lavasa","doi":"10.1007/s11207-025-02486-0","DOIUrl":"10.1007/s11207-025-02486-0","url":null,"abstract":"<div><p>High energy solar protons were observed by particle detectors aboard spacecraft in near-Earth orbit on May 11, 2024 and produced the 74^th ground level enhancement (GLE74) event registered by ground-based neutron monitors. This study involves a detailed reconstruction of the neutron monitor response, along with the identification of the solar eruption responsible for the emission of the primary particles, utilizing both in situ and remote-sensing. Observations spanning proton energies from a few MeV to around 1.64 GeV, collected from the Solar and Heliospheric Observatory (SOHO), the Geostationary Operational Environmental Satellite (GOES), the Solar Terrestrial Relations Observatory (STEREO-A), and neutron monitors, were integrated with records of the associated solar soft X-ray flare, coronal mass ejection, and radio bursts, to identify the solar origin of the GLE74. Additionally, a time-shift analysis was conducted to link the detected particles to their solar sources. Finally, a comparison of GLE74 to previous ones is carried out. GLE74 reached a maximum particle rigidity of at least 2.4 GV and was associated with a series of type III, type II, and type IV radio bursts. The release time of the primary solar energetic particles (SEPs) with an energy of 500 MeV was estimated to be around 01:21 UT. A significant SEP flux was observed from the anti-Sun direction with a relatively broad angular distribution, rather than a narrow, beam-like pattern, particularly during the main phase at the particle peak flux. Comparisons with previous GLEs suggest that GLE74 was a typical event in terms of solar eruption dynamics.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"300 5","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11207-025-02486-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145171515","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}

{"title":"Sunrise iii: Overview of Observatory and Instruments","authors":"Andreas Korpi-Lagg,&nbsp;Achim Gandorfer,&nbsp;Sami K. Solanki,&nbsp;Jose Carlos del Toro Iniesta,&nbsp;Yukio Katsukawa,&nbsp;Pietro Bernasconi,&nbsp;Thomas Berkefeld,&nbsp;Alex Feller,&nbsp;Tino L. Riethmüller,&nbsp;Alberto Álvarez-Herrero,&nbsp;Masahito Kubo,&nbsp;Valentín Martínez Pillet,&nbsp;H. N. Smitha,&nbsp;David Orozco Suárez,&nbsp;Bianca Grauf,&nbsp;Michael Carpenter,&nbsp;Alexander Bell,&nbsp;María-Teresa Álvarez-Alonso,&nbsp;Daniel Álvarez García,&nbsp;Beatriz Aparicio del Moral,&nbsp;Julia Atiénzar,&nbsp;Daniel Ayoub,&nbsp;Francisco Javier Bailén,&nbsp;Eduardo Bailón Martínez,&nbsp;Maria Balaguer Jiménez,&nbsp;Peter Barthol,&nbsp;Montserrat Bayon Laguna,&nbsp;Luis R. Bellot Rubio,&nbsp;Melani Bergmann,&nbsp;Julian Blanco Rodríguez,&nbsp;Jan Bochmann,&nbsp;Juan Manuel Borrero,&nbsp;Antonio Campos-Jara,&nbsp;Juan Sebastián Castellanos Durán,&nbsp;María Cebollero,&nbsp;Aitor Conde Rodríguez,&nbsp;Werner Deutsch,&nbsp;Harry Eaton,&nbsp;Ana Belen Fernández-Medina,&nbsp;German Fernandez-Rico,&nbsp;Agustin Ferreres,&nbsp;Andrés García,&nbsp;Ramón María García Alarcia,&nbsp;Pilar García Parejo,&nbsp;Daniel Garranzo-García,&nbsp;José Luis Gasent Blesa,&nbsp;Karin Gerber,&nbsp;Dietmar Germerott,&nbsp;David Gilabert Palmer,&nbsp;Laurent Gizon,&nbsp;Miguel Angel Gómez Sánchez-Tirado,&nbsp;David González-Bárcena,&nbsp;Alejandro Gonzalo Melchor,&nbsp;Sam Goodyear,&nbsp;Hirohisa Hara,&nbsp;Edvarda Harnes,&nbsp;Klaus Heerlein,&nbsp;Frank Heidecke,&nbsp;Jan Heinrichs,&nbsp;David Hernández Expósito,&nbsp;Johann Hirzberger,&nbsp;Johannes Hoelken,&nbsp;Sangwon Hyun,&nbsp;Francisco A. Iglesias,&nbsp;Ryohtaroh T. Ishikawa,&nbsp;Minwoo Jeon,&nbsp;Yusuke Kawabata,&nbsp;Martin Kolleck,&nbsp;Hugo Laguna,&nbsp;Julian Lomas,&nbsp;Antonio C. López Jiménez,&nbsp;Paula Manzano,&nbsp;Takuma Matsumoto,&nbsp;David Mayo Turrado,&nbsp;Thimo Meierdierks,&nbsp;Stefan Meining,&nbsp;Markus Monecke,&nbsp;José Miguel Morales-Fernández,&nbsp;Antonio Jesús Moreno Mantas,&nbsp;Alejandro Moreno Vacas,&nbsp;Marc Ferenc Müller,&nbsp;Reinhard Müller,&nbsp;Yoshihiro Naito,&nbsp;Eiji Nakai,&nbsp;Armonía Núñez Peral,&nbsp;Takayoshi Oba,&nbsp;Geoffrey Palo,&nbsp;Isabel Pérez-Grande,&nbsp;Javier Piqueras Carreño,&nbsp;Tobias Preis,&nbsp;Damien Przybylski,&nbsp;Carlos Quintero Noda,&nbsp;Sandeep Ramanath,&nbsp;Jose Luis Ramos Más,&nbsp;Nour Raouafi,&nbsp;María-Jesús Rivas-Martínez,&nbsp;Pedro Rodríguez Martínez,&nbsp;Manuel Rodríguez Valido,&nbsp;Basilio Ruiz Cobo,&nbsp;Antonio Sánchez Rodríguez,&nbsp;Mariano Sanchez Toledo,&nbsp;Antonio Sánchez Gómez,&nbsp;Esteban Sanchis Kilders,&nbsp;Kamal Sant,&nbsp;Pablo Santamarina Guerrero,&nbsp;Erich Schulze,&nbsp;Toshifumi Shimizu,&nbsp;Manuel Silva-López,&nbsp;Kunal Singh,&nbsp;Azaymi L. Siu-Tapia,&nbsp;Thomas Sonner,&nbsp;Jan Staub,&nbsp;Hanna Strecker,&nbsp;Angel Tobaruela,&nbsp;Ignacio Torralbo,&nbsp;Alexandra Tritschler,&nbsp;Toshihiro Tsuzuki,&nbsp;Fumihiro Uraguchi,&nbsp;Reiner Volkmer,&nbsp;Angelos Vourlidas,&nbsp;Dušan Vukadinović,&nbsp;Stephan Werner,&nbsp;Andreas Zerr","doi":"10.1007/s11207-025-02485-1","DOIUrl":"10.1007/s11207-025-02485-1","url":null,"abstract":"<div><p>In July 2024, <span>Sunrise</span> completed its third successful science flight. The <span>Sunrise iii</span> observatory had been upgraded significantly after the two previous successful flights in 2009 and 2013, to tackle the most recent science challenges concerning the solar atmosphere. Three completely new instruments focus on the small-scale physical processes and their complex interaction from the deepest observable layers in the photosphere up to chromospheric heights. Previously poorly explored spectral regions and lines are exploited to paint a three-dimensional picture of the solar atmosphere with unprecedented completeness and level of detail.</p><p>The full polarimetric information is captured by all three instruments to reveal the interaction between the magnetic fields and the hydrodynamic processes. Two slit-based spectropolarimeters, the <span>Sunrise</span> UV Spectropolarimeter and Imager (SUSI) and the <span>Sunrise</span> Chromospheric Infrared spectro-Polarimeter (SCIP), focus on the near-ultraviolet (309 – 417 nm) and the near-infrared (765 – 855 nm) regions respectively, and the imaging spectropolarimeter Tunable Magnetograph (<span>TuMag</span>) simultaneously obtains maps of the full field-of-view of <span>(46times 46)</span> Mm² in the photosphere and the chromosphere in the visible (525 and 517 nm). The instruments are operated in an orchestrated mode, benefiting from a new Image Stabilization and Light Distribution unit (<span>ISLiD</span>), with the Correlating Wavefront Sensor (CWS) providing the autofocus control and an image stability with a root-mean-square value smaller than 0.005”. A new gondola was constructed to significantly improve the telescope pointing stability, required to achieve uninterrupted observations over many hours.</p><p><span>Sunrise iii</span> was launched successfully on 10 July 2024, from the Esrange Space Center of the Swedish Space Corporation near Kiruna (Sweden). It reached the landing site between the Mackenzie River and the Great Bear Lake in Canada after a flight duration of 6.5 days. In this paper, we give an overview of the <span>Sunrise iii</span> observatory and its instruments.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"300 5","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11207-025-02485-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145170940","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}

{"title":"Time Path of Turbulence and Multi-Fractality of Magnetic Field in the Evolution of an Active Region","authors":"Valentina Abramenko","doi":"10.1007/s11207-025-02484-2","DOIUrl":"10.1007/s11207-025-02484-2","url":null,"abstract":"<div><p>Magnetograms acquired with the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory (SDO) were used to calculate and analyze time variations of turbulence and multifractality in the photosphere during the development and flaring of a mature active region NOAA 13354 during its passage across the solar disk. Turbulence was explored with 2D magnetic power spectra from magnetograms, and multifractality was analyzed using the structure functions of magnetograms. Time variations of the magnetic power spectrum exponent <span>(alpha )</span> and of the multifractality exponent <span>(kappa )</span> demonstrate no pre-flare or post-flare abrupt peculiarities, instead, long periods of stability with smooth transitions into other conditions were observed. A conclusion was inferred that the turbulence and multifractality time path in the photospheric magnetic field does not follow the timing of single flares, however, it tends to correspond to the levels of the magneto-morphological complexity and flaring productivity of an AR. So, in the sense of self-organized criticality (SOC), the photosphere, being in the state of self-organization, evolves independently from the highly intermittent, SOC-state corona.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"300 5","pages":""},"PeriodicalIF":2.4,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145170941","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}

{"title":"Data Processing Pipeline of the SUTRI EUV Imager on the SATech-01 Satellite","authors":"Ziyao Hu,&nbsp;Kaifan Ji,&nbsp;Xianyong Bai,&nbsp;Xiao Yang,&nbsp;Yuanyong Deng,&nbsp;Wei Duan,&nbsp;Zhenyong Hou,&nbsp;Zihao Yang","doi":"10.1007/s11207-025-02483-3","DOIUrl":"10.1007/s11207-025-02483-3","url":null,"abstract":"<div><p>Solar observations in extreme ultraviolet (EUV) wavelengths are a crucial component of solar activity research and space weather forecasting. The Solar Upper Transition Region Imager (SUTRI) on the SATech-01 satellite is designed to take full-disk solar images in the Ne <span>vii</span> 46.5 nm spectral line (T = 0.5 MK). It was launched in 2022 and the science data were released on January 10, 2023. In this article, we describe the data preprocessing method employed to SUTRI data to eliminate inherent instrument effects and standardize the raw data to obtain scientific data. Alongside common data processing steps, our pipeline includes correcting for horizontal stripes from the CMOS imaging camera. As an experiment payload, SUTRI does not have an image stabilization system. Thus, a multi-step iterative algorithm has been developed to precisely align series of drifted images due to the limited pointing accuracy of the satellite platform. Our method may not be limited to SUTRI; it also serves as a reference for future solar EUV telescope data processing.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"300 5","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11207-025-02483-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144140126","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}

{"title":"Structure and Dynamics of the Sun’s Interior Revealed by the Helioseismic and Magnetic Imager","authors":"Alexander G. Kosovichev,&nbsp;Sarbani Basu,&nbsp;Yuto Bekki,&nbsp;Juan Camilo Buitrago-Casas,&nbsp;Theodosios Chatzistergos,&nbsp;Ruizhu Chen,&nbsp;Jørgen Christensen-Dalsgaard,&nbsp;Alina Donea,&nbsp;Bernhard Fleck,&nbsp;Damien Fournier,&nbsp;Rafael A. García,&nbsp;Alexander V. Getling,&nbsp;Laurent Gizon,&nbsp;Douglas O. Gough,&nbsp;Shravan Hanasoge,&nbsp;Chris S. Hanson,&nbsp;Shea A. Hess Webber,&nbsp;J. Todd Hoeksema,&nbsp;Rachel Howe,&nbsp;Kiran Jain,&nbsp;Spiridon Kasapis,&nbsp;Samarth G. Kashyap,&nbsp;Irina N. Kitiashvili,&nbsp;Rudolf Komm,&nbsp;Sylvain G. Korzennik,&nbsp;Natalie A. Krivova,&nbsp;Jeffrey R. Kuhn,&nbsp;Zhi-Chao Liang,&nbsp;Charles Lindsey,&nbsp;Sushant S. Mahajan,&nbsp;Krishnendu Mandal,&nbsp;Prasad Mani,&nbsp;Juan Carlos Martinez Oliveros,&nbsp;Savita Mathur,&nbsp;M. Cristina Rabello Soares,&nbsp;S. Paul Rajaguru,&nbsp;Johann Reiter,&nbsp;Edward J. Rhodes Jr.,&nbsp;Jean-Pierre Rozelot,&nbsp;Philip H. Scherrer,&nbsp;Sami K. Solanki,&nbsp;John T. Stefan,&nbsp;Juri Toomre,&nbsp;Sushanta C. Tripathy,&nbsp;Lisa A. Upton,&nbsp;Junwei Zhao","doi":"10.1007/s11207-025-02480-6","DOIUrl":"10.1007/s11207-025-02480-6","url":null,"abstract":"<div><p>High-resolution helioseismology observations with the Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics Observatory (SDO) provide a unique three-dimensional view of the solar interior structure and dynamics, revealing a tremendous complexity of the physical processes inside the Sun. We present an overview of the results of the HMI helioseismology program and discuss their implications for modern theoretical models and simulations of the solar interior.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"300 5","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11207-025-02480-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144135280","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}

{"title":"Linear Correlation Between Radial and Normal Component Fluctuations of the Interplanetary Magnetic Field","authors":"Munetoshi Tokumaru,&nbsp;Nishiki Nozaki,&nbsp;Ken’ichi Fujiki","doi":"10.1007/s11207-025-02475-3","DOIUrl":"10.1007/s11207-025-02475-3","url":null,"abstract":"<div><p>The interplanetary magnetic field (IMF), particularly its north–south component, acts as a key parameter for controlling the space weather effect of solar wind disturbances on the Earth; therefore, accurate understanding of the behavior of the IMF is important for improvement of space weather prediction. This study reports the relation between radial (<span>(B_{r})</span>) and normal (<span>(B_{n})</span>) components of IMF by analyzing in situ observations collected by inner- and outer-heliosphere spacecraft over multiple solar cycles. A quadratic relation between <span>(B_{r})</span> and <span>(B_{n})</span> with a 22-year periodicity which corresponds to the magnetic polarity cycle of the Sun was observed in IMF data of the inner-heliosphere spacecraft. In contrast, IMF data of the outer-heliosphere spacecraft did not show such a quadratic relation but exhibited a linear relation between <span>(B_{r})</span> and <span>(B_{n})</span> with a slope and correlation coefficient depending on the latitude: positive and negative slopes (correlation coefficients) were revealed from the IMF data for north and south latitudes, respectively, and those magnitudes increased with the latitude. Slopes and correlation coefficients of the linear relation depended on neither the radial distance nor the solar activity. The same linear relation between <span>(B_{r})</span> and <span>(B_{n})</span> was found for the IMF data of the inner-heliosphere spacecraft by sorting them into two groups in terms of the latitude. Therefore, quadratic relation was ascribed to the combined effect of the latitude variation of the inner-heliosphere spacecraft and the latitude dependence of the linear relation. Although the physical process to generate the linear relation remains an open question, some kind of MHD waves may be responsible for it.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"300 5","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11207-025-02475-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144140203","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}

{"title":"Comparison of Polar Magnetic Fields Derived from MILOS and MERLIN Inversions with Hinode/SOT-SP Data","authors":"Masahito Kubo,&nbsp;Daikou Shiota,&nbsp;Yukio Katsukawa,&nbsp;Masumi Shimojo,&nbsp;David Orozco Suárez,&nbsp;Nariaki Nitta,&nbsp;Marc DeRosa,&nbsp;Rebecca Centeno,&nbsp;Haruhisa Iijima,&nbsp;Takuma Matsumoto,&nbsp;Satoshi Masuda","doi":"10.1007/s11207-025-02487-z","DOIUrl":"10.1007/s11207-025-02487-z","url":null,"abstract":"<div><p>The detailed investigation of the polar magnetic field and its time evolution is one of the major achievements of Hinode. Precise measurements of the polar magnetic field are essential for understanding the solar cycle, as they provide important constraints for identifying the source regions of the solar wind. The Spectropolarimeter (SP) of the Solar Optical Telescope (SOT) on board Hinode has been the instrument best suited to make such measurements. In this study, we compare the SOT-SP data for the polar regions, processed using two representative Milne-Eddington inversion codes, MILOS and MERLIN. These codes are applied to the same level-1 SOT-SP data, and the same disambiguation algorithm is used on the maps that go through the two inversions. We find that the radial magnetic-flux density (the magnetic-flux density with respect to the local vertical) provided by the MERLIN inversion tends to be approximately 7% – 10% larger than that obtained from the MILOS inversion. The slightly higher radial magnetic-flux density from MERLIN appears to be common to the polar magnetic fields observed at different phases of the solar cycle. When MILOS is run with the same scattered-light profile and the same magnetic filling factor that are derived with the MERLIN inversion, the radial magnetic-flux density derived from the two inversions is almost the same. We attribute the difference in the radial magnetic-flux density to different filling factors adopted by the two inversions, based on whether the scattered-light profiles are assumed to be the Stokes I profiles averaged over the neighboring pixels or over the entire field of view. The relationship between the radial magnetic-flux density and magnetic filling factor could be more complex in the polar (limb) observations due to the possible contributions of the transverse magnetic-field component to the estimation of the radial magnetic-flux density.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"300 5","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144125859","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}