The time series of daily data on solar activity proxies, namely the sunspot number(SSN), sunspot area(SSA), solar radio flux(F10.7), modified coronal index(MCI), solar flare index(FI), and cosmic ray intensity(CRI), w...The time series of daily data on solar activity proxies, namely the sunspot number(SSN), sunspot area(SSA), solar radio flux(F10.7), modified coronal index(MCI), solar flare index(FI), and cosmic ray intensity(CRI), were analyzed to understand the solar activity modulations and short-term periodicities therein. Rieger-type and other short-term periods include the solar rotational period that covers the maximum activity phase period(maximum phase of solar cycle 24). The wavelet power spectra and Periodogram of SSN, SSA, F10.7, MCI, FI, and CRI exhibited a significant short-term period. The heliospheric effects exist for a particular period(~27 days) and they are related to the solar activity phenomena. The cross-correlation coefficients and time lags between the CRI and solar activity parameters were estimated to be ~200, 46, 281, 39, and 47 days for SSN, SSA, F10.7, MCI, and FI respectively during the time series 2012–2015(maximum phase of solar cycle 24).展开更多
文摘The time series of daily data on solar activity proxies, namely the sunspot number(SSN), sunspot area(SSA), solar radio flux(F10.7), modified coronal index(MCI), solar flare index(FI), and cosmic ray intensity(CRI), were analyzed to understand the solar activity modulations and short-term periodicities therein. Rieger-type and other short-term periods include the solar rotational period that covers the maximum activity phase period(maximum phase of solar cycle 24). The wavelet power spectra and Periodogram of SSN, SSA, F10.7, MCI, FI, and CRI exhibited a significant short-term period. The heliospheric effects exist for a particular period(~27 days) and they are related to the solar activity phenomena. The cross-correlation coefficients and time lags between the CRI and solar activity parameters were estimated to be ~200, 46, 281, 39, and 47 days for SSN, SSA, F10.7, MCI, and FI respectively during the time series 2012–2015(maximum phase of solar cycle 24).
