Geomagnetism and Aeronomy最新文献_第5页

The Influence of Explosive Processes in Active Regions on the Characteristics of the Magnetic Field in the Umbra of Sunspots Depending on Their Size and Position 活动区爆炸过程对太阳黑子本影磁场特性的影响与黑子大小和位置的关系

IF 0.7 4区地球科学

Geomagnetism and Aeronomy Pub Date : 2025-02-14 DOI: 10.1134/S001679322470049X

Yu. S. Zagainova, V. G. Fainshtein, G. V. Rudenko

引用次数: 0

Modeling of Time Profiles of Solar Energetic Particle Events 太阳高能粒子事件的时间分布模型

IF 0.7 4区地球科学

Geomagnetism and Aeronomy Pub Date : 2025-02-14 DOI: 10.1134/S0016793224700439

D. V. Rozhkova, L. K. Kashapova, I. N. Myagkova

{"title":"Modeling of Time Profiles of Solar Energetic Particle Events","authors":"D. V. Rozhkova, L. K. Kashapova, I. N. Myagkova","doi":"10.1134/S0016793224700439","DOIUrl":"10.1134/S0016793224700439","url":null,"abstract":"Solar energetic particle (SEP) events are mostly generated by solar flares. They can be associated not only with flares that occur on the visible side of the Sun but also on the backside. It is noted that the shape of the time profiles of SEP events associated with flares on the back side of the Sun does not correspond to the typical impulsive or gradual time profiles. X-rays are the main source of information about the processes of energy release and particle acceleration in solar flares. For many years, information on this type of emission for flares on the back side of the Sun was rare. Nowadays, the ability to obtain this type of information is becoming more and more available. We present the results of testing numerical model realized as a code that makes it possible to reproduce the shape of the time profile of SEP events using simple assumptions about particle propagation into the interplanetary space. The time profiles of SEP protons with energies above 30 MeV have been modeled assuming that the particles were accelerated only in the solar atmosphere during the flare. Tests have been done for four impulsive flares that occurred in the western hemisphere of the Sun and in the center of the solar disk. We simulated the time profile of an SEP event, the source of which was a flare that possibly occurred on the backside of the Sun on October 21, 2003. The results, possibilities for model improvements, and the application of this method to the study of SEP events with no source on the visible side of the Sun are discussed.","PeriodicalId":55597,"journal":{"name":"Geomagnetism and Aeronomy","volume":"64 8","pages":"1310 - 1317"},"PeriodicalIF":0.7,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143423091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Monthly Mean Sunspot Areas in the Last 275 Years 过去275年的月平均太阳黑子面积

IF 0.7 4区地球科学

Geomagnetism and Aeronomy Pub Date : 2025-02-14 DOI: 10.1134/S0016793224700518

Yu. A. Nagovitsyn, S. N. Fedoseeva, A. A. Osipova

引用次数: 0

Heliogeophysical Features and Viral Epidemics of the 21st Century 21世纪的太阳地球物理特征和病毒流行

IF 0.7 4区地球科学

Geomagnetism and Aeronomy Pub Date : 2025-02-14 DOI: 10.1134/S0016793224700397

M. V. Ragulskaya, V. N. Obridko

{"title":"Heliogeophysical Features and Viral Epidemics of the 21st Century","authors":"M. V. Ragulskaya, V. N. Obridko","doi":"10.1134/S0016793224700397","DOIUrl":"10.1134/S0016793224700397","url":null,"abstract":"Heliogeophysical features of the 21st century are considered. It is discussed that the low solar dynamics of cycles 24 and 25 manifested themselves not only in sunspot number, but also as a significant decrease in geomagnetic events, decreased intensity of solar cosmic rays, and increased intensity of galactic cosmic rays. Changes in the solar GMF and a significant decrease in the amplitude of odd harmonics of the global magnetic field (GMF) of the Sun were also observed. It is proposed to use the maximum of the fifth zonal harmonic of the solar GMF as a predictor of the time of the maximum of the 11-year solar activity cycle, and the polar field of the Sun to predict the height of the cycle. The maximum of the 25th cycle of solar activity (SA) predicted by the authors was expected at the end of 2023–beginning of 2024 with a cycle height of no more than 131. A secondary solar activity maximum is possible during 2025. Epidemiological processes can serve as an additional predictor of global changes in solar activity. The number of viral pandemics during the 19th–21st centuries was tripled near centennial solar activity minima. Measles epidemics are developing approximately a year prior to the onset of extrema of the 11-year solar activity cycle. It is emphasized that the role of solar activity minima in the development of viral epidemics is significantly underestimated.","PeriodicalId":55597,"journal":{"name":"Geomagnetism and Aeronomy","volume":"64 8","pages":"1288 - 1294"},"PeriodicalIF":0.7,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143423083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Efficiency of Acceleration of Nonthermal Electrons with Whistler Turbulence in a Flare Loop Depending on Its Frequency Spectrum 耀斑环中非热电子在惠斯勒湍流中的加速效率随其频谱的变化

IF 0.7 4区地球科学

Geomagnetism and Aeronomy Pub Date : 2025-02-14 DOI: 10.1134/S0016793224700506

L. V. Filatov, V. F. Melnikov

引用次数: 0

A Critical Investigation on the Reliability of GPS-Derived TEC Data at Agra for Earthquake Predictions by Using the Support Vector Machine (SVM) Algorithm 基于支持向量机（SVM）算法的阿格拉地区gps TEC数据地震预报可靠性研究

IF 0.7 4区地球科学

Geomagnetism and Aeronomy Pub Date : 2025-02-14 DOI: 10.1134/S0016793224700324

Swati, Devbrat Pundhir, Birbal Singh, Saral Kumar Gupta

{"title":"A Critical Investigation on the Reliability of GPS-Derived TEC Data at Agra for Earthquake Predictions by Using the Support Vector Machine (SVM) Algorithm","authors":"Swati, Devbrat Pundhir, Birbal Singh, Saral Kumar Gupta","doi":"10.1134/S0016793224700324","DOIUrl":"10.1134/S0016793224700324","url":null,"abstract":"In the present paper, a long period of GPS-TEC observed at Agra station, India has been investigated to develop a support vector machine (SVM)-based model corresponding to earthquakes that occurred around Agra within 2000 km from 2010 to 2013. The different datasets are prepared with the help of the GPS‑TEC data, solar activity (R and F10.7 cm), magnetic storm (Dst and ∑Kp indices) parameters, etc. for the magnitude in the range of 4–7.7 at the interval of 0.5 and outer radius of 2000 km at the interval of 500 km. Here, 90% of the data is used for training, and the rest of the 10% of data is used for test purposes. These parameters are used as the input in the Linear and Medium Gaussian SVM models, respectively. The confusion matrices are obtained for each dataset and then skill scores such as precision, recall, and accuracy are calculated, statistically. The best results of skill scores are obtained in the case of magnitude range 4–7.7 and the outer radius of 2000 km. The receiver output characteristics (ROC) curves are plotted and the maximum accuracy of 94% is obtained. A k-fold cross-validation (k = 5) technique is used to validate our models. Further, both models are compared by using the Wilcoxon signed-rank test. Bayesian Optimizer optimizes the GPS-TEC datasets. Finally, these models may be utilized for real-time data classification.","PeriodicalId":55597,"journal":{"name":"Geomagnetism and Aeronomy","volume":"64 8","pages":"1225 - 1236"},"PeriodicalIF":0.7,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143423226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dependence of Solar Wind Speed on the Area of Coronal Holes and Saturation Effect 日冕洞面积与饱和效应对太阳风速度的影响

IF 0.7 4区地球科学

Geomagnetism and Aeronomy Pub Date : 2025-02-14 DOI: 10.1134/S0016793224700415

Z. S. Akhtemov, Y. T. Tsap

{"title":"Dependence of Solar Wind Speed on the Area of Coronal Holes and Saturation Effect","authors":"Z. S. Akhtemov, Y. T. Tsap","doi":"10.1134/S0016793224700415","DOIUrl":"10.1134/S0016793224700415","url":null,"abstract":"Recently, Samara et al. (2022) showed that proportionality between the solar fast wind velocity V from the low latitude coronal holes (CH) and their area Sch is satisfied only for small-sized CH, while the saturation effect for larger CH is revealed; i.e., a plateau is formed in a V(Sch) plot. This is explained by the geometric complexity of CH, described by the fractal dimension. Previously, Akhtemov and Tsap (2018, 2019) established that the correlation coefficient between V and Sch reaches a maximum for a CH located within a fractional area ±10° in longitude and ±40° in latitude. They suggested that this inference is related to the radial propagation of the solar wind and, hence, the increasing of Sch should not be accompanied by an increase of V for large CH. The presented work provides a detailed comparative analysis of the results obtained by Samara et al. (2022) and Akhtemov and Tsap (2018, 2019). Arguments are given in favor of the model related to the saturation effect with the radial propagation of the fast solar wind.","PeriodicalId":55597,"journal":{"name":"Geomagnetism and Aeronomy","volume":"64 8","pages":"1299 - 1302"},"PeriodicalIF":0.7,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143423340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Anomalous Heating of the Upper Layers of the Solar Chromosphere by Slow Magnetohydrodynamic Shock Waves 慢磁激波对太阳色球层上层的异常加热

IF 0.7 4区地球科学

Geomagnetism and Aeronomy Pub Date : 2025-02-14 DOI: 10.1134/S0016793224700385

K. V. Romanov, D. V. Romanov, V. A. Romanov, E. A. Stepanov, A. A. Lebedev

引用次数: 0

Trigger Effects of Space Weather Impact on Earth Tectonics and Their Impact on Climate 空间天气对地球构造的触发效应及其对气候的影响

IF 0.7 4区地球科学

Geomagnetism and Aeronomy Pub Date : 2025-02-14 DOI: 10.1134/S0016793224700488

B. P. Komitov, V. I. Kaftan

引用次数: 0

A Statistical Analysis of Parameters of Type III Radio Bursts According to Solar Spectropolarimeter of Meter Range (SSMD) Data 基于太阳光谱偏振计（SSMD）数据的III型射电暴参数统计分析

IF 0.7 4区地球科学

Geomagnetism and Aeronomy Pub Date : 2025-02-14 DOI: 10.1134/S0016793224700452

N. O. Muratova, L. K. Kashapova

{"title":"A Statistical Analysis of Parameters of Type III Radio Bursts According to Solar Spectropolarimeter of Meter Range (SSMD) Data","authors":"N. O. Muratova, L. K. Kashapova","doi":"10.1134/S0016793224700452","DOIUrl":"10.1134/S0016793224700452","url":null,"abstract":"In the paper, we present an analysis of the parameters of type III radio bursts registered in the range of 50–500 MHz by the Solar Spectropolarimeter of Meter Range (SSMD) of the radio astrophysical observatory of the Institute of Solar-Terrestrial Physics, Siberian Branch, Russian Academy of Sciences during the period of solar activity minimum from 2016 to 2019. In the study, an original method for identifying type III radio bursts has been developed and used with allowance for the features of the data related to the time and spectral resolution of the device. Most of the studied events are associated with B-class flares according to the GOES classification and lower. However, the distribution of events according to the velocities of the electrons generated the radio bursts emission does not differ from the standard distribution, including for powerful flares. A general tendency for an increase in the duration of a radio burst with a decrease in the energy of the electrons that generated it has been revealed. The electron energy band width is about one order of magnitude. The events of 2017 associated with powerful flares are at the upper limit of the energies of this band.","PeriodicalId":55597,"journal":{"name":"Geomagnetism and Aeronomy","volume":"64 8","pages":"1328 - 1333"},"PeriodicalIF":0.7,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143423089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0