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arXiv · 2302.00289

Solar radio bursts observations by Egypt- Alexandria CALLISTO spectrometer: First results

F. N. Minta·S. Nozawa·K. Kozarev·A. Elsaid·A. Mahrous
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Abstract

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 appeared to be in the center of the CALLISTO network of spectrometers. Moreover, in the northern section of Africa, the Egypt-Alexandria CALLISTO and ALGERIA-CRAAG stations are the only ones operating. There are no stations in the West African region, while stations in the eastern part of Africa are not working. Thus, Egypt- Alexandria station serves as a reference for other stations within the e-CALLISTO network. Despite the low solar activity, the instrument detected several solar radio bursts not limited to type II, type III, and type V. A vigorous case study was conducted on two selected radio burst events to validate the authenticity of the recorded events. Other solar radio stations at different geographical locations recorded all the radio bursts detected by the spectrometer. The case study included brief analyses that indicated a type II radio burst observed on October 09, 2021, between 06:30 and 07:00 UT, was associated with an M1.6 solar flare located at N18E08 within NOAA-AR 12882 and a CME with a shock front speed of ~978 km/s. However, the type III radio burst is neither CME nor solar flare associated. These analyses examine the instrument's capacity to provide real-time solar radio transient data 24 hours a day to mitigate the challenges of data gaps faced in the African continent. Hence, the instrument has become an integral part of space weather monitoring and forecasting over the region and other parts of the globe.

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F. N. Minta, S. Nozawa, K. Kozarev, A. Elsaid, A. Mahrous. 2023-02-01. Solar radio bursts observations by Egypt- Alexandria CALLISTO spectrometer: First results. https://doi.org/10.1016/j.asr.2022.06.054

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