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A note on using thermally driven solar wind models in MHD space weather simulations

Published online by Cambridge University Press:  08 June 2011

Jens Pomoell
Affiliation:
Department of Physics, University of Helsinki, P.O. Box 64, 00014, University of Helsinki, Finland email: [email protected], [email protected]
Rami Vainio
Affiliation:
Department of Physics, University of Helsinki, P.O. Box 64, 00014, University of Helsinki, Finland email: [email protected], [email protected]
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Abstract

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One of the challenges in constructing global magnetohydrodynamic (MHD) models of the inner heliosphere for, e.g., space weather forecasting purposes, is to correctly capture the acceleration and expansion of the solar wind. In many current models, the solar wind is driven by varying the polytropic index so that a desired heating is obtained. While such schemes can yield solar wind properties consistent with observations, they are not problem-free. In this work, we demonstrate by performing MHD simulations that altering the polytropic index affects the properties of propagating shocks significantly, which in turn affect the predicted space weather conditions. Thus, driving the solar wind with such a mechanism should be used with care in simulations where correctly capturing the shock physics is essential. As a remedy, we present a simple heating function formulation by which the polytropic wind can be used while still modeling the shock physics correctly.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2011

References

Parker, E. N. 1958, ApJ, 128, 664CrossRefGoogle Scholar
Cranmer, S. R. 2010, SSRv, doi:10.1007/s11214-010-9674-7Google Scholar
Cohen, O., Sokolov, I. V., Roussev, I. I., & Gombosi, T. I. 2008, JGR 113, A03104Google Scholar
Reames, D. V. 1999, SSRv 90, 413Google Scholar