000004329 001__ 4329
000004329 005__ 20191216113029.0
000004329 037__ $$aCTALK-2019-0139
000004329 100__ $$aShestov, S
000004329 245__ $$aTitle: Initiation of Alfvénic turbulence by Alfvén wave collisions: a numerical study
000004329 260__ $$c2019
000004329 269__ $$c2019-08-29
000004329 520__ $$aAccording to the recent theory of Alfvénic turbulence, the turbulent cascade generated by Alfvén-wave collisions proceeds along the critically balanced path in the wavenumber space, where the linear propagation time of Alfvén waves adjusts to their nonlinear interaction time. We study numerically elementary Alfvén-wave collisions and demonstrate that, contrary to theoretical expectations, the critically balanced collisions provide a relatively weak spectral transport insufficient to generate strong Alfvénic turbulence. We also show that the strong turbulence can be generated by the collisions of Alfvén waves with perpendicular wavelengths shifted to shorter scales as compared to the critically-balanced path. The spectral transport in both cases generates perturbations with perpendicular (to the mean magnetic field) scales smaller than in the original waves and with different polarization, which qualitatively agrees with theoretical predictions. We discuss effects that can suppress the critically-balanced collisions and related consequences for the turbulent plasma heating in the solar coronal loops and solar wind.
000004329 536__ $$a3PRODPROBA3/$$c3PRODPROBA3/$$f3PRODPROBA3
000004329 594__ $$aNO
000004329 6531_ $$aTurbulence
000004329 6531_ $$aAlfven waves
000004329 6531_ $$aMHD
000004329 700__ $$aVoitenko, Y
000004329 700__ $$aZhukov, A
000004329 773__ $$tFifth Uk-Ukraine-Spain meeting on Solar Physics and Space Sciences
000004329 8560_ $$fsergei.shestov@observatoire.be
000004329 85642 $$ahttp://pdg.group.shef.ac.uk/Conferences/UKUS_2019/
000004329 906__ $$aContributed
000004329 980__ $$aCTALKCONT