Spectrum of a random f -mode and the SOHO/MDI data
نویسنده
چکیده
According to the SOHO/MDI observations (Duvall et al. 1998, Antia & Basu 1999) the solar f-mode frequency departs from the parabolic dispersion relation ω2 = gk. We propose to explain this behaviour in terms of a spaceand timedependent random flow that occurs in the convection zone. A time-dependent random flow speeds up the f-mode while the effect of a space-dependent random flow is to slow it down. A competition between these two effects brings a reduction of frequencies and a line-width increase at low l. Theoretical estimation of the frequency shift and line-width leads to a conclusion that for l < 2000 the results are consistent with the recent SOHO/MDI data.
منابع مشابه
Randomly generated spectrum of the solar f-mode
We show that a random flow that depends on space and time generates a mode which is damped and move slower than the coherent f-mode as well as possesses properties which are consistent with the recent SOHO/MDI data (Antia & Basu 1999).
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