Spectral properties of anisotropic two-dimensional magnetohydrodynamic turbulence

We performed numerical simulations of two-dimensional magnetohydrodynamic (2D MHD) turbulence on an 8192^{2} grid with mean magnetic fields B_{0}=0,1, 3, 6, and 10. The energy spectra and fluxes of Elsässer variables are in better agreement with Kolmogorov-like phenomenology (k^{-5/3}) than Iroshnikov-Kraichnan phenomenology (k^{-3/2}). Our numerical study shows that k_{∥}∝k_{⊥} for all B_{0}, which is contrary to the predictions of "critical balance." Additionally, the averaged alignment angle between the velocity and magnetic fluctuations remains constant across all length scales, contrary to the predictions of dynamic alignment. These results indicate that local alignment and antialignment events coexist but statistically balance each other, leading to an overall absence of scale-dependent alignment. Thus, our results demonstrate violations of both critical-balance and dynamic alignment in 2D MHD turbulence. We explore regimes up to B_{0}/δb≈10, over which k^{-5/3} spectral scaling is observed, relevant to solar-wind turbulence near 1 AU and beyond.