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Large solar energetic particles and solar radio emissions during Cycle 25. A comparative analysis of trends and characteristics with cycles 23 and 24
Ndacyayisenga, Theogene; Uwamahoro, Jean; Uwamahoro, Jean Claude +2 more
Solar energetic particles (SEPs) affect space weather in both the heliosphere and on Earth. The present study investigates the occurrences of large SEP events focusing on their influence on the Earth, as well as their correlation with solar radio bursts (SRBs). The velocity dispersion analysis (VDA) is used to calculate the release times of large …
Analysis of global ionospheric scintillation and GPS positioning interference triggered by full-halo CME-driven geomagnetic storm: A case study
Zhao, Dongsheng; Cui, Shuanglei; Zhang, Xueli +7 more
Currently, the 25th solar activity peak has commenced, driving frequent geomagnetic storms and causing irregular disturbances in the global ionosphere, leading to the scintillation of Global Positioning System (GPS) signals, consequently decreasing the accuracy of GPS positioning. Analyzing the patterns of global ionospheric scintillation and chan…
Type II radio bursts and space weather phenomena: A statistical study
Chandra, Ramesh; Miteva, Rositsa; Koleva, Kostadinka +2 more
In this paper, we present for the first time a comprehensive statistical study between type II radio bursts from the metric (m) to the dekameric–hectometric (DH) domain and their associated solar and space weather (SW) phenomena, namely, solar flares (SFs), sunspot (SN) configurations, filament eruptions, coronal mass ejections (CMEs), their inter…
Correlations between space weather parameters during intense geomagnetic storms: Analytical study
Miteva, Rositsa; Samwel, Susan
We explore the correlation between different parameters of space weather events associated with intense geomagnetic disturbances that occurred during the solar cycles (SCs) 23 and 24 (1996-2019). The space weather events under this study are the Solar Flares (SFs), Coronal Mass Ejections (CMEs), Geomagnetic Storms (GSs), Solar Energetic Protons (S…
Relationships between energetic storm particle events and interplanetary shocks driven by full and partial halo coronal mass ejections
Vainio, Rami; Valtonen, Eino; Al-Sawad, Amjad +1 more
We have analysed energetic storm particle (ESP) events in 116 interplanetary (IP) shocks driven by front-side full and partial halo coronal mass ejections (CMEs) with speeds > 400 km s-1during the years 1996-2015. We investigated the occurrence and relationships of ESP events with several parameters describing the IP shocks, and the …
The north-south asymmetry of active regions of different magneto-morphological types in solar cycles 23 and 24
Zhukova, Anastasiya; Sokoloff, Dmitry; Abramenko, Valentina +1 more
We used the elaborated earlier catalog of the magneto-morphological classes (MMC) of active regions (ARs) to study 2046 ARs of the solar cycle (SC) 23 and 1507 ARs of the SC24. According to empiric rules for sunspot groups (Hale's polarity law, Joy's law, etc.) and MMC, all ARs (except for unipolar spots) were sorted out between two categories: A-…
Assessing the spectral characteristics of band splitting type II radio bursts observed by CALLISTO spectrometers
Kozarev, Kamen; Minta, Felix N.; Nozawa, Satoshi I. +2 more
Metric type II radio bursts are usually early indicators of CME-driven shocks and other space weather phenomena in the solar corona. This paper presents a detailed investigation of the spectral properties of band splitting type II radio bursts and their association with sunspot number. Using type II radio bursts in a frequency range [20 MHz-200 MH…
Characteristics of X-class flares of solar cycles 23 and 24 in X-ray and EUV bands
Bhardwaj, Anil; Kumar, A.; Chakrabarty, D. +4 more
The characteristics of X-class flares of solar cycles 23 and 24 are examined based on the soft X-ray (0.1-0.8 nm) and EUV (26-34 nm) light curves. First, the commonly used correction factors for the center-to-limb variation of EUV flux are compared. Subsequently, enhancements in X-ray and EUV levels are used to calculate the relative apportionment…
New insights from cross-correlation studies between solar activity indices and cosmic-ray flux during Forbush decrease events
Savić, Mihailo; Veselinović, Nikola; Dragić, Aleksandar +5 more
Observed galactic cosmic ray intensity can be subjected to a transient decrease. These so-called Forbush decreases are driven by coronal mass ejection induced shockwaves in the heliosphere. By combining in situ measurements by space borne instruments with ground-based cosmic ray observations, we investigate the relationship between solar energetic…
Solar radio bursts observations by Egypt- Alexandria CALLISTO spectrometer: First results
Kozarev, K.; Minta, F. N.; Nozawa, S. I. +2 more
The newly installed CALLISTO spectrometer, hosted by the Department of Space Environment, Institute of Basic and Applied Sciences- EJUST, commenced operation on August 14, 2021. The system contains a cross dipole long-wavelength array antenna with high sensitivity to monitor solar radio transients. Its antenna was strategically positioned and appe…