Whistler-mode waves inside flux pileup region: Structured or unstructured?

0441007 - ÚFA 2015 RIV US eng J - Článek v odborném periodiku
Fu, H. S. - Cao, J. B. - Cully, C. M. - Khotyaintsev, Y. V. - Vaivads, A. - Angelopoulos, V. - Zong, Q. -G. - Santolík, Ondřej - Macúšová, Eva - Andre, M. - Liu, W. L. - Lu, H. Y. - Zhou, M. - Huang, S. Y. - Zhima, Z.
Whistler-mode waves inside flux pileup region: Structured or unstructured?
2169-9380. Journal of Geophysical Research-Space Physics. Roč. 119, č. 11 (2014), s. 9089-9100. ISSN 2169-9380. E-ISSN 2169-9402
Grant CEP: GA MŠMT 7E12026
Institucionální podpora: RVO:68378289
Klíčová slova: flux pileup region * dipolarization front * whistler * chorus * structure * magnetic field inhomogeneity
Kód oboru RIV: BL - Fyzika plazmatu a výboje v plynech
Impakt faktor: 3.426, rok: 2014
http://onlinelibrary.wiley.com/doi/10.1002/2014JA020204/abstract

During reconnection, a flux pileup region (FPR) is formed behind a dipolarization front in an outflow jet. Inside the FPR, the magnetic field magnitude and Bz component increase and the whistler-mode waves are observed frequently. As the FPR convects toward the Earth during substorms, it is obstructed by the dipolar geomagnetic field to form a near-Earth FPR. Unlike the structureless emissions inside the tail FPR, we find that the whistler-mode waves inside the near-Earth FPR can exhibit a discrete structure similar to chorus. Both upper band and lower band chorus are observed, with the upper band having a larger propagation angle (and smaller wave amplitude) than the lower band. Most chorus elements we observed are “rising-tone” type, but some are “falling-tone” type. We notice that the rising-tone chorus can evolve into falling-tone chorus within <3 s. One of the factors that may explain why the waves are unstructured inside the tail FPR but become discrete inside the near-Earth FPR is the spatial inhomogeneity of magnetic field: we find that such inhomogeneity is small inside the near-Earth FPR but large inside the tail FPR.
Trvalý link: http://hdl.handle.net/11104/0244944