p-mode eigenfunctions by the magnetic field [@2009SoPh..258....1B and references therein].

Another possibility that could alter p-mode damping is variations in the convective properties near the solar surface, which are most likely to arise from the influence of magnetic structures [@2001MNRAS.327..483H]. @2001MNRAS.327..483H theorized that changes of parameters in the convection zone would affect linewidth shapes mainly in the plateau region of a frequency spectrum, as is observed. This, therefore, implies that during times of high-magnetic activity the convection zone is affected sufficiently to produce a measurable change in p-mode linewidths. Several authors have observed that the horizontal size of solar granules decreases from solar minimum to solar maximum . @1988AdSpR...8..159M found that the horizontal granule size decreased by approximately 5% from solar minimum to solar maximum. According to @2001MNRAS.327..483H this should result in an increase in damping rates of about 20%, which is in reasonable agreement with the observed change in damping rates in BiSON data of approximately $24\pm3$%.

We now return to look in more detail at the changes in frequencies of the p modes with solar cycle.

Dependence of solar cycle frequency shifts on $l$ and frequency
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Solar cycle frequency shifts, $\delta\nu_{n,l}$, have well-known dependencies on both angular 