Assessing the spectral characteristics of band splitting type II radio bursts observed by CALLISTO spectrometers. (arXiv:2301.13839v1 [astro-ph.SR])
<a href="http://arxiv.org/find/astro-ph/1/au:+Minta_F/0/1/0/all/0/1">F. N. Minta</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Nozawa_S/0/1/0/all/0/1">S. Nozawa</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kamen_K/0/1/0/all/0/1">K. Kamen</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Elsaid_A/0/1/0/all/0/1">A. Elsaid</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ayman_A/0/1/0/all/0/1">A. Ayman</a>
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 to 200MHz observed by CALLISTO from 2010 to
2017, it was discovered that the analyzed type II shock height, magnetic field
strength, CME shock speed, and Alfven speed synchronize with the trajectory of
the solar cycle 24. Also, the study revealed that the onset of the declining
phase of solar cycle 24 has the highest electron density. The analysis
ascertained that the frequency of type II bursts depicts a bimodal distribution
during the study period, with peaks in 2012 and 2015. Further, a good
correlation(with correlation factor R=0.87) was obtained between the estimated
CME shock speeds from the dynamic spectra, and the associated CME speeds from
SOHO-LASCO. Moreover, the study confirmed a significant correlation(R=0.8)
between the absolute drift rates and the plasma frequency. Additionally, the
study explored that 60% of the type II radio bursts considered in this study
emanated from the western longitudes. Hence, these findings emphasize that the
temporal dynamics of the physical conditions of band-splitting type II radio
are essential parameters in space weather monitoring and forecasting.
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 to 200MHz observed by CALLISTO from 2010 to
2017, it was discovered that the analyzed type II shock height, magnetic field
strength, CME shock speed, and Alfven speed synchronize with the trajectory of
the solar cycle 24. Also, the study revealed that the onset of the declining
phase of solar cycle 24 has the highest electron density. The analysis
ascertained that the frequency of type II bursts depicts a bimodal distribution
during the study period, with peaks in 2012 and 2015. Further, a good
correlation(with correlation factor R=0.87) was obtained between the estimated
CME shock speeds from the dynamic spectra, and the associated CME speeds from
SOHO-LASCO. Moreover, the study confirmed a significant correlation(R=0.8)
between the absolute drift rates and the plasma frequency. Additionally, the
study explored that 60% of the type II radio bursts considered in this study
emanated from the western longitudes. Hence, these findings emphasize that the
temporal dynamics of the physical conditions of band-splitting type II radio
are essential parameters in space weather monitoring and forecasting.
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