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In a recent paper [P. H. Yoon and G. Choe, Phys. Plasmas 28, 082306 (2021)], the weak turbulence theory for incompressible magnetohydrodynamics is formulated by employing the method customarily applied in the context of kinetic weak plasma turbulence theory. Such an approach simplified certain mathematical procedures including achieving the closure relationship. The formulation in the abovecited paper starts from the equations of incompressible magnetohydrodynamic (MHD) theory expressed via Elsasser variables. The derivation of nonlinear wave kinetic equation therein is obtained via a truncated solution at the secondorder of iteration following the standard practice. In the present paper, the weak MHD turbulence theory is alternatively formulated by employing the pristine form of incompressible MHD equation rather than that expressed in terms of Elsasser fields. The perturbative expansion of the nonlinear momentum equation is carried out up to the thirdorder iteration rather than imposing the truncation at the second order. It is found that while the resulting wave kinetic equation is identical to that obtained in the previous paper cited above, the thirdorder nonlinear correction plays an essential role for properly calculating derived quantities such as the total and residual energies.
 Publication Date:
 NSFPAR ID:
 10378865
 Journal Name:
 Physics of Plasmas
 Volume:
 29
 Issue:
 11
 Page Range or eLocationID:
 Article No. 112303
 ISSN:
 1070664X
 Publisher:
 American Institute of Physics
 Sponsoring Org:
 National Science Foundation
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