MHD-Kinetic Transition in Imbalanced Alfvénic Turbulence
| dc.contributor.author | Voitenko, Y. | |
| dc.contributor.author | De Keyser, J. | |
| dc.date | 2016 | |
| dc.date.accessioned | 2016-12-21T10:09:38Z | |
| dc.date.available | 2016-12-21T10:09:38Z | |
| dc.identifier.uri | https://orfeo.belnet.be/handle/internal/4688 | |
| dc.description | Alfvénic turbulence in space is usually imbalanced: amplitudes of waves propagating parallel and anti-parallel to the mean magnetic field B0 are unequal. It is commonly accepted that the turbulence is driven by (counter-) collisions between these counter-propagating wave fractions. Contrary to this, we found a new ion-scale dynamical range of the turbulence established by (co-)collisions among waves co-propagating in the same direction along B0. Co-collisions become stronger than counter-collisions and produce steep non-universal spectra above certain wavenumbers dependent on the imbalance. Spectral indexes of the strong turbulence vary around ≳-3, such that steeper spectra follow larger imbalances. Intermittency steepens the -3 spectra further, up to -3.7. Our theoretical predictions are compatible with steep variable spectra observed in the solar wind at ion kinetic scales, but further verifications are needed by correlating observed spectra with measured imbalances. | |
| dc.language | eng | |
| dc.title | MHD-Kinetic Transition in Imbalanced Alfvénic Turbulence | |
| dc.type | Article | |
| dc.subject.frascati | Physical sciences | |
| dc.audience | Scientific | |
| dc.source.title | Astrophysical Journal Letters | |
| dc.source.volume | 832 | |
| dc.source.issue | 2 | |
| dc.source.page | L20 | |
| Orfeo.peerreviewed | Yes | |
| dc.identifier.doi | 10.3847/2041-8205/832/2/L20 | |
| dc.identifier.scopus | 2-s2.0-85000796436 |
