ASTRONOMY AND ASTROPHYSICS Heating of coronal holes by phase mixing
نویسندگان
چکیده
A two-dimensional, analytical, self-similar solution to the Alfvén wave phase mixing equations is presented for a coronal hole model. The solution shows clearly that the damping of the waves with height follows the scaling predicted by Heyvaerts & Priest 1983 at low heights, before switching to an algebraic decay at large heights. The ohmic dissipation is calculated and it is shown that the maximum dissipation occurs at a height that scales with η 1/3. However, the total Ohmic dissipa-tion is, of course, independent of the resistivity. Using realistic solar parameters it appears that phase mixing is a viable mechanism for heating the lower corona provided either the frequency of photospheric motions is sufficiently large or the background Alfvén velocity is sufficiently small.
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