Solar Physics最新文献

{"title":"Magnetohydrodynamic Turbulence Simulations as a Testing Ground for PUNCH","authors":"Francesco Pecora,&nbsp;Yan Yang,&nbsp;Sarah Gibson,&nbsp;Nicholeen M. Viall,&nbsp;Rohit Chhiber,&nbsp;Craig DeForest,&nbsp;William H. Matthaeus","doi":"10.1007/s11207-024-02382-z","DOIUrl":"10.1007/s11207-024-02382-z","url":null,"abstract":"<div><p>The Polarimeter to UNify the Corona and Heliosphere (PUNCH) will image macroscopic features of the inner heliosphere and also admit sufficiently high spatial resolution to probe scales of turbulence within the upper end of the inertial range, close to the integral scale. As PUNCH is an imager, its measurements will relate differently to the underlying turbulent environment of the outer corona and inner heliosphere from more familiar in situ samples. We present a numerical study that combines magnetohydrodynamic simulations of turbulence together with FORWARD-modeling synthesis of white-light data via the FORWARD code. We show that (i) the “usual” turbulence scalings are modified by the integration along the LOS in an optically thin medium, and (ii) those scalings are still linked to the original properties of the turbulent field. This study is a first step in the process of analyzing and understanding the unprecedented information that PUNCH will provide.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"299 10","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11207-024-02382-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142409518","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":"Science Operation and Data Analysis Center of the Advanced Space-Based Solar Observatory (ASO-S) Mission","authors":"Yu Huang,&nbsp;Youping Li,&nbsp;Suo Liu,&nbsp;Jiangtao Su,&nbsp;Li Feng,&nbsp;Ying Li,&nbsp;Yang Su,&nbsp;Wei Chen,&nbsp;Dong Li,&nbsp;Shijun Lei,&nbsp;Yingna Su,&nbsp;Yunyi Ge,&nbsp;Lei Lu,&nbsp;Jingwei Li,&nbsp;Hui Li,&nbsp;Weiqun Gan","doi":"10.1007/s11207-024-02368-x","DOIUrl":"10.1007/s11207-024-02368-x","url":null,"abstract":"<div><p>A reliable data analysis center plays a crucial role in the successful execution of a space mission. The Science Operation and Data analysis Center (SODC) of Advanced Space-based Solar Observatory (ASO-S) is a bridge between the science team of ASO-S and data users (Huang et al. 2019). ASO-S plays a crucial role in understanding the solar eruptions (such as flares and coronal mass ejections) and the magnetism behind them. In this article, we outline the current status of ASO-S, as well as its data products and analysis software. These resources aid in the enhanced understanding of solar magnetism and its associated energetic eruptions.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"299 9","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142414487","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":"Diagnostics of Solar Corona Heating Parameters Using the Observed Gravitational Stratification of the Medium","authors":"Dmitrii Riashchikov,&nbsp;Elizaveta Scoptsova,&nbsp;Dmitrii Zavershinskii","doi":"10.1007/s11207-024-02383-y","DOIUrl":"10.1007/s11207-024-02383-y","url":null,"abstract":"<div><p>The problem of coronal heating is one of the fundamental problems of solar physics. At present, it is again attracting great interest due to the appearance of a large amount of observational data of high spatial and temporal resolution. These data made it possible to diagnose plasma parameters from observations of waves and oscillations in coronal magnetic structures and, moreover, to introduce analytical constraints on the coronal heating function. In this paper, we propose an approach allowing us to impose constraints on the heating function based on data on the gravitational stratification of the solar atmosphere. The developed algorithm is applied to the altitude profiles of temperature and density in several regions of the solar corona obtained from direct modeling of EUV radiation from the <i>Solar Dynamics Observatory/Atmospheric Imaging Assembly</i> (SDO/AIA). Assuming that the heating function is a power function of temperature and density, we determine the domain of power-index constraints allowing us to realize the observed altitude profiles. The obtained results are combined with the conditions of stability for the entropy and magnetoacoustic modes, to narrow the region of possible parameters further.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"299 9","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142414436","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":"Classifying Different Types of Solar-Wind Plasma with Uncertainty Estimations Using Machine Learning","authors":"Tom Narock,&nbsp;Sanchita Pal,&nbsp;Aryana Arsham,&nbsp;Ayris Narock,&nbsp;Teresa Nieves-Chinchilla","doi":"10.1007/s11207-024-02379-8","DOIUrl":"10.1007/s11207-024-02379-8","url":null,"abstract":"<div><p>Decades of in-situ solar-wind measurements have clearly established the variation of solar-wind physical parameters. These variable parameters have been used to classify the solar-wind magnetized plasma into different types, leading to several classification schemes being developed. These classification schemes, while useful for understanding the solar wind’s originating processes at the Sun and early detection of space weather events, have left open questions regarding which physical parameters are most useful for classification and how recent advances in our understanding of solar-wind transients impact classification. In this work, we use neural networks trained with different solar-wind magnetic and plasma characteristics to automatically classify the solar wind in coronal hole, streamer belt, sector reversal and solar transients such as coronal mass ejections comprised of both magnetic obstacles and sheaths. Furthermore, our work demonstrates how probabilistic neural networks can enhance the classification by including a measure of prediction uncertainty. Our work also provides a ranking of the parameters that lead to an improved classification scheme with <span>(sim 96%)</span> accuracy. Our new scheme paves the way for incorporating uncertainty estimates into space-weather forecasting with the potential to be implemented on real-time solar-wind data.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"299 9","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142413668","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":"Characterizing High-Energy Solar Proton Events with Energies Below and Above 100 MeV","authors":"Dheyaa Ameri,&nbsp;Eino Valtonen,&nbsp;Amjad Al-Sawad,&nbsp;Rami Vainio","doi":"10.1007/s11207-024-02378-9","DOIUrl":"10.1007/s11207-024-02378-9","url":null,"abstract":"&lt;div&gt;&lt;p&gt;We analyzed 58 high-energy proton events that occurred during the years 1996 – 2022. In 32 out of the 58 (55%) events, the proton energies extended up to &lt;span&gt;(sim 68)&lt;/span&gt; MeV but did not reach 100 MeV. In the remaining 26 events, the proton energies exceeded 100 MeV. We studied the differences in the characteristics of these proton events and their associations with solar and interplanetary phenomena to improve understanding proton sources and acceleration processes.&lt;/p&gt;&lt;p&gt;The coronal mass ejections (CMEs) associated with &lt;span&gt;(&gt;100)&lt;/span&gt; MeV proton events appeared to be, on average, more energetic than those associated with &lt;span&gt;(&lt; 100)&lt;/span&gt; MeV proton events. The peak and integrated fluxes (fluence) of the soft X-ray (SXR) flares were higher in &gt; 100 MeV proton events, but there was almost no difference in the rise times of the flares. In a major part of the &lt;span&gt;(&gt; 100)&lt;/span&gt; MeV proton events, protons were released over the rise phase of the SXR flares, whereas in most of the &lt;span&gt;(&lt;100)&lt;/span&gt; MeV events the proton releases occurred after the peak of the SXR flares. We established limits for the CME speed V&lt;sub&gt;CME&lt;/sub&gt; and SXR peak flux F&lt;sub&gt;pk&lt;/sub&gt; or total fluence F&lt;sub&gt;&lt;i&gt;i&lt;/i&gt;&lt;/sub&gt;, which helped us to distinguish the events in the two groups. Solar eruptions with V&lt;sub&gt;CME&lt;/sub&gt; &lt;span&gt;(&gt; 1000)&lt;/span&gt; km s&lt;sup&gt;−1&lt;/sup&gt; and F&lt;span&gt;(_{mathrm{pk}} &gt; 5 cdot 10^{-5} )&lt;/span&gt; W m&lt;sup&gt;−2&lt;/sup&gt; had a high probability to produce proton events of &lt;span&gt;(&gt; 100)&lt;/span&gt; MeV. On the other hand, eruptions with V&lt;span&gt;(_{mathrm{CME}} &gt; 900)&lt;/span&gt; km s&lt;sup&gt;−1&lt;/sup&gt; and F&lt;span&gt;(_{i} &lt;5 cdot 10^{-4} )&lt;/span&gt; J m&lt;sup&gt;−2&lt;/sup&gt; and eruptions with V&lt;span&gt;(_{ mathrm{CME}} &lt; 900)&lt;/span&gt; km s&lt;sup&gt;−1&lt;/sup&gt; irrespective of the SXR total fluence were very likely to produce proton events of &lt;span&gt;(&lt; 100)&lt;/span&gt; MeV.&lt;/p&gt;&lt;p&gt;All proton events were associated with decametric Type III radio bursts, and most of them had Type II bursts associations either in metric or decametric–hectometric (DH) wavelengths or both. Both metric- and DH-Type II emissions were observed in 50% of &lt;span&gt;(&lt;100)&lt;/span&gt; MeV proton events while they were observed in 88% of &lt;span&gt;(&gt;100)&lt;/span&gt; MeV events. Our analysis showed that protons in most of the &lt;span&gt;(&gt;100)&lt;/span&gt; MeV events were released low in the corona (&lt;span&gt;(leq 3.0)&lt;/span&gt; R&lt;sub&gt;⊙&lt;/sub&gt;) before the onsets of the DH-Type II radio bursts. Conversely, protons in most of the &lt;span&gt;(&lt;100)&lt;/span&gt; MeV events were released higher in the corona (&lt;span&gt;(&gt;3)&lt;/span&gt; R&lt;sub&gt;⊙&lt;/sub&gt;) and after the DH-Type II onsets.&lt;/p&gt;&lt;p&gt;We conclude that protons in most of the &lt;span&gt;(&gt; 100)&lt;/span&gt; MeV events are accelerated either by the flare reconnection processes or by shocks low in the corona and could undergo reacceleration higher in the corona in CME shocks manifested in DH-Type II radio emission. In the &lt;span&gt;(&lt;100)&lt;/span&gt; MeV events, protons are mainly accelerated in CME sho","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"299 9","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11207-024-02378-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142413778","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":"Latitudinal Dependence of Variations in the Frequencies of Solar Oscillations Above the Acoustic Cut-Off","authors":"Laura Jade Millson,&nbsp;Anne-Marie Broomhall,&nbsp;Tishtrya Mehta","doi":"10.1007/s11207-024-02369-w","DOIUrl":"10.1007/s11207-024-02369-w","url":null,"abstract":"<div><p>At high frequencies beyond the acoustic cut-off, a peak-like structure is visible in the solar power spectrum. Known as the pseudo-modes, their frequencies have been shown to vary in anti-phase with solar magnetic activity. In this work, we determined temporal variations in these frequencies across the solar disc, with the aim of identifying any potential latitudinal dependence of pseudo-mode frequency shifts. We utilised nearly 22 years of spatially resolved GONG data for all azimuthal orders, <span>(textit{m})</span>, for harmonic degrees <span>(0leq lleq 200)</span>, and determined shifts using the resampled periodogram method. Periodogram realisations were created from overlapping, successive 216 day-long segments in time, and cropped to 5600 – 6800 μHz. Cross-correlation functions were then repeatedly generated between these realisations to identify any variation in frequency and the uncertainty. We categorised each mode by its latitudinal sensitivity and used this categorisation to produce average frequency shifts for different latitude bands (15^∘ and 5^∘ in size) which were compared to magnetic proxies, the <span>(F_{mathrm{10.7}})</span> index and GONG synoptic maps. Morphological differences in the pseudo-mode shifts between different latitudes were found, which were most pronounced during the rise to solar maximum where shifts reach their minimum values. At all latitudes, shift behaviour was strongly in anti-correlation with the activity proxy. Additionally, periodicities shorter than the 11-year cycle were observed. Wavelet analysis was used to identify a periodicity of four years at all latitudes.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"299 9","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11207-024-02369-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142413711","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":"The Spectro-Polarimeter of the Andrei B. Severny Solar Tower Telescope at the Crimean Astrophysical Observatory: Optical Design and Implementation","authors":"Alexander Kutsenko,&nbsp;Valery Terebizh,&nbsp;Andrei Dolgopolov,&nbsp;Valentina Abramenko,&nbsp;Andrei Plotnikov,&nbsp;Dmitriy Semyonov,&nbsp;Vladimir Skiruta,&nbsp;Vyacheslav Lopukhin","doi":"10.1007/s11207-024-02380-1","DOIUrl":"10.1007/s11207-024-02380-1","url":null,"abstract":"<div><p>The <i>Spectro-Polarimeter</i> (SP) is a new instrument installed at the upgraded <i>Andrei B. Severny Solar Tower Telescope</i> (STT) at the <i>Crimean Astrophysical Observatory</i>. The instrument is a traditional echelle slit dual-beam spectropolarimeter with temporal modulation of the polarization. STT-SP provides simultaneous spectropolarimetric observations of the Sun within three 15 Å wide spectral ranges around photospheric Fe I 5250 Å, Fe I 5324 Å, and chromospheric Mg I b2 5172 Å spectral lines. The spectral resolution of the instrument reaches 70,000 with the seeing-constrained slit width of 1 arcsec. The field-of-view of STT-SP is 200 arcsec allowing one to map a moderate size active region within a single raster scan. The instrument will provide new opportunities in the analysis of magnetic fields and thermodynamics of the lower atmosphere of the Sun. In this paper we describe the optical design of STT-SP and present the preliminary results acquired during the commissioning of the instrument.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"299 9","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142413773","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":"A Linear Analysis of Torsional Alfvén Waves in Open Twisted Divergent Magnetic Flux Tubes for Coronal Heating","authors":"Bivek Pradhan,&nbsp;Gobinda Chandra Mishra,&nbsp;Pralay Kumar Karmakar,&nbsp;Utpal Deka","doi":"10.1007/s11207-024-02372-1","DOIUrl":"10.1007/s11207-024-02372-1","url":null,"abstract":"<div><p>The torsional Alfvén wave is highly regarded as the carrier of the energy from the photosphere to the corona in the solar atmosphere. This paper presents a comprehensive linear analysis of the wave behavior and energy transfer within an open, twisted, divergent magnetic flux tube configuration, considering the impact of wave guide structure on the propagation of these waves using the magneto-hydrodynamic approach. The study shows that waves with frequencies between 0.001 Hz and 1 Hz can effectively penetrate the transition region, with the most efficient energy transfer occurring in the 0.1 Hz to 1 Hz frequency range. The research findings suggest that waves with certain intermediate frequencies are able to transmit energy to the coronal region of the Sun, contributing to its active heating.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"299 9","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11207-024-02372-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142412781","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":"The Current State of the Controversy over Screening in Nuclear Reactions","authors":"Werner Däppen","doi":"10.1007/s11207-024-02377-w","DOIUrl":"10.1007/s11207-024-02377-w","url":null,"abstract":"<div><p>A controversy about the possibility of dynamic effects in nuclear screening has been around for several decades. On the one hand, there is the claim that there are no dynamic effects and that the classic Salpeter correction based on static Debye screening is all that is needed for astrophysical applications. The size of the correction is on the order of 5% in typical solar fusion reactions. On the other hand, numerical simulations have shown that there is a dynamical effect, which essentially cancels the Salpeter correction. The results of the numerical simulations were later independently confirmed. The astrophysical community, however, has so far largely ignored the possibility of dynamical screening. The present paper is meant to serve as a reminder of the controversy. Not only does the claim of an absence of a dynamical effect equally warrant an independent confirmation, but there is motivation for further investigation, such as the assessment of current laboratory experiments and a quantitative study of the dynamical effect in case it will turn out to be real.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"299 9","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142412774","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":"Comparative Study of Solar Rotation of Transition Region and Corona using Solar Irradiance and Radio Flux","authors":"Avneesh Kumar,&nbsp;Nagendra Kumar,&nbsp;Hari Om Vats","doi":"10.1007/s11207-024-02375-y","DOIUrl":"10.1007/s11207-024-02375-y","url":null,"abstract":"<div><p>We study the temporal variation of solar rotation profiles based on solar irradiance at 93.5 nm and solar radio flux at 10.7 cm originating from the transition region and lower corona, respectively. The autocorrelation technique is used to calculate the period in periodic time series data. The sidereal rotation periods for normalized and detrended data are studied for 2011 – 2021. The sidereal rotation periods for solar irradiance and radio flux for 2011 – 2021 vary from 22.75 to 26.17 days and 19.42 to 28.14 days, respectively. The mean of the sidereal rotation periods for solar irradiance and radio flux are 24.76 and 23.76 days, respectively. The mean sidereal rotation period for solar irradiance is higher than the mean sidereal rotation period for solar radio flux. The sidereal rotation period for solar irradiance is greater than or equal to the sidereal rotation period for solar radio flux for almost all the years between 2011 and 2021. It is found that the lower corona rotates faster than the transition region during 2011 – 2021, i.e., the lower corona is found to be moving 4% faster than the transition region during 2011 – 2021. We found a linear relationship between the normalized daily irradiance and radio flux with a correlation coefficient of 0.986. Using cross-correlation analysis, we investigated a phase relationship between solar irradiance and radio flux and found no time lag between solar irradiance and radio flux.</p></div>","PeriodicalId":777,"journal":{"name":"Solar Physics","volume":"299 9","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142412811","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}