The contribution to p-mode line widths from the excitation of tube mode oscillations on an individual magnetic Ðbril is computed. An idealized model of the Ðbril within the photosphere is implemented, consisting of a vertical, thin magnetic Ñux tube embedded in a plane-parallel isentropic polytrope of index m. Bogdan et al. considered a similar model but imposed a stress-free boundary condition at the top of the photosphere, which acts to reÑect any upward-propagating tube waves completely back

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... down into the tube. The stress-free boundary condition neglects a possibly important physical process : the loss of energy to the upper solar atmosphere by the excitation of waves in the chromosphere and corona. Using simple models of the solar chromosphere and corona, we explore the consequences of applying various boundary conditions. The resultant upward energy Ñuxes are not large, but surprisingly the more realistic upper boundary conditions lead to a signiÐcant increase in kink mode Ñux out the bottom. Nevertheless, the sausage mode remains dominant in cases of interest and is essentially una †ected by the new boundary conditions. Consequently, the resultant total p-mode line width computed here can account for only a few percent of the observed line width.