Abstract
Recent numerical investigations of wave propagation near coronal magnetic null points (McLaughlin and Hood: Astron. Astrophys. 459, 641, 2006) have indicated how a fast MHD wave partially converts into a slow MHD wave as the disturbance passes from a low-β plasma to a high-β plasma. This is a complex process and a clear understanding of the conversion mechanism requires the detailed investigation of a simpler model. An investigation of mode conversion in a stratified, isothermal atmosphere with a uniform, vertical magnetic field is carried out, both numerically and analytically. In contrast to previous investigations of upward-propagating waves (Zhugzhda and Dzhalilov: Astron. Astrophys. 112, 16, 1982a; Cally: Astrophys. J. 548, 473, 2001), this paper studies the downward propagation of waves from a low-β to high-β environment. A simple expression for the amplitude of the transmitted wave is compared with the numerical solution.
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References
Abramowitz, M., Stegun, I.A.: 1964, Handbook of Mathematical Functions, National Bureau of Standards, Washington, 686.
Bender, C.M., Orszag, S.A.: 1978, Advanced Mathematical Methods for Scientists and Engineers, McGraw-Hill, Singapore, 486.
Bloomfield, D.S., McAteer, R.T.J., Mathioudakis, M., Keenan, F.P.: 2006, Astrophys. J. 652, 812.
Bogdan, T.J., Carlsson, M., Hansteen, V., McMurray, A., Rosenthal, C.S., Johnson, M., Petty-Powell, S., Zita, E.J., Stein, R.F., McIntosh, S.W., Nordlund, Å.: 2003, Astrophys. J. 599, 626.
Cairns, R.A., Fuchs, V.: 1989, Phys. Fluids B 1, 350.
Cairns, R.A., Lashmore-Davies, C.N.: 1983, Phys. Fluids 26, 1268.
Cairns, R.A., Lashmore-Davies, C.N.: 1986, Phys. Fluids 29, 3639.
Cally, P.S.: 2001, Astrophys. J. 548, 473.
Cally, P.S.: 2006, Philos. Trans. Roy. Soc. A 364, 333.
Carlsson, M., Bogdan, T.J.: 2006, Philos. Trans. Roy. Soc. A 364, 395.
Ferraro, V.C.A., Plumpton, C.: 1958, Astrophys. J. 127, 459.
Khomenko, E., Collados, M.: 2006, Astrophys. J. 653, 739.
McLaughlin, J.A., Hood, A.W.: 2006, Astron. Astrophys. 459, 641.
Roberts, B.: 2006, Philos. Trans. Roy. Soc. A 364, 447.
Rosenthal, C.S., Bogdan, T.J., Carlsson, M., Dorch, S.B.F., Hansteen, V., McIntosh, S.W., McMurray, A., Nordlund, Å., Stein, R.F.: 2002, Astrophys. J. 564, 508.
Schunker, H., Cally, P.S.: 2006, Mon. Not. Roy. Astron. Soc. 372, 551.
Stein, R.F.: 1971, Astrophys. J. Suppl. 192(22), 419.
Zhugzhda, Y.D.: 1979, Sov. Astron. 23, 42.
Zhugzhda, Y.D., Dzhalilov, N.S.: 1981, Sov. Astron. 25, 477.
Zhugzhda, Y.D., Dzhalilov, N.S.: 1982a, Astron. Astrophys. 112, 16.
Zhugzhda, Y.D., Dzhalilov, N.S.: 1982b, Sov. J. Plasma Phys. 8, 558.
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McDougall, A.M.D., Hood, A.W. A New Look at Mode Conversion in a Stratified Isothermal Atmosphere. Sol Phys 246, 259–271 (2007). https://doi.org/10.1007/s11207-007-0393-5
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DOI: https://doi.org/10.1007/s11207-007-0393-5