2009/07/26 by Stanislav Boldyrev, Jean Carlos Perez · 1 citation
Physics and Astronomy · #astro-ph.GA #physics.plasm-ph
paper · pdf · doi:10.1103/physrevlett.103.225001
published as Phys. Rev. Lett. 103, 225001 (2009) · 4 pages, 3 figures
Turbulence of magnetohydrodynamic waves in nature and in the laboratory is generally cross-helical or non-balanced, in that the energies of Afvén waves moving in opposite directions along the guide magnetic field are unequal. Based on high-resolution numerical simulations it is proposed that such turbulence spontaneously generates a condensate of the residual energy Ev-Eb at small field-parallel wave numbers. As a result, the energy spectra of counter-propagating Alfvén waves are not scale-invariant. In the limit of infinite Reynolds number, the universality is asymptotically restored at large wave numbers, and both spectra attain the scaling E(k)∝ k⊥-2. The generation of condensate is apparently related to the breakdown of mirror symmetry in non-balanced turbulence.