SOLAR CYCLE INDUCED VARIATIONS IN GONG p-MODE FREQUENCIES AND SPLITTINGS
نویسندگان
چکیده
We have analysed the recently available GONG p-mode frequencies and splitting coefficients for a period of three and half years, including the rapidly rising phase of solar cycle 23. The analysis of mean frequency shift with different activity indices shows that the shift is equally correlated with both magnetic and radiative indices. During the onset of the new cycle 23, we notice that the change in b4 splitting coefficient is more prominent than the change in b2. We have estimated the solar rotation rate with varying depth and latitude. In the equatorial region, the rotation first increases with depth and then decreases, while an opposite behaviour is seen in the polar region. We also find a small but significant temporal variation in the rotation rate at high latitudes. Subject headings: Sun: activity – Sun: oscillations – Sun: rotation
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