ar X iv : a st ro - p h / 02 05 14 1 v 1 9 M ay 2 00 2 To appear in ApJ What Causes P - mode Asymmetry Reversal ?
نویسندگان
چکیده
The solar acoustic p-mode line profiles are asymmetric. Velocity spectra have more power on the low-frequency sides, whereas intensity profiles show the opposite sense of asymmetry. Numerical simulations of the upper convection zone have resonant p-modes with the same asymmetries and asymmetry reversal as the observed modes. The temperature and velocity power spectra at optical depth τ cont = 1 have the opposite asymmetry as is observed for the intensity and velocity spectra. At a fixed geometrical depth, corresponding to < τ cont >= 1, however, the temperature and velocity spectra have the same asymmetry. This indicates that the asymmetry reversal is produced by radiative transfer effects and not by correlated noise.
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