EAGER: A First Principles Test of the Current Sheet Heating Hypothesis for the Solar Corona

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The Principal Investigator (PI) will test a long-standing hypothesis that solar coronal heating occurs in sub-resolution current sheets. The PI notes that theoretical estimates suggest that the thickness of such current sheets in the solar corona would be on the order of 100 meters or less, but there is no firm evidence that such sheets exist. These current sheets cannot be observed directly due to the inadequate spatial resolution of current observing technology. Since these sheets cannot yet be detected, the PI asserts that an indirect test for their existence would be to determine if magnetohydrodynamic (MHD) models can give rise to such phenomena from first principles physics, without in any way predisposing the MHD model to have current sheet solutions in the corona. The PI will create such a model and require that such solutions "arise naturally" from the intrinsic, nonlinear transport and radiation physics within the model. The PI's model will be designed to provide exact, self-consistent solutions for sub-resolution, heated, radiating current sheets under solar coronal conditions, and include realistic mathematical expressions for the radiative cooling rate and the anisotropic transport coefficients that determine solar coronal heating. If the PI finds his anticipated current sheet solutions, then these would constitute the first theoretical evidence for the existence of current sheets in the solar corona and would lend support to the current sheet coronal heating hypothesis. Such solutions would contribute to our fundamental understanding of radiation generation and anisotropic transport processes in current sheets and would permit more accurate multi-dimensional MHD simulations for increasing our understanding of magnetic reconnection, a phenomenon that is pervasive in space physics, astrophysics, and plasma physics. Magnetic reconnection is also a key phenomenon in the most energetic space weather events.