%0 Conference Proceedings
%4 sid.inpe.br/mtc-m21c/2018/12.03.15.16
%2 sid.inpe.br/mtc-m21c/2018/12.03.15.16.55
%T South America monsoon system and features simulated by the Eta regional model
%D 2018
%A Ericksson, Stefan,
%A Souza, Vitor Moura Cardoso e Silva,
%A Cassak, Paul,
%@affiliation Laboratory for Atmospheric and Space Physics
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation West Virginia University
%@electronicmailaddress
%@electronicmailaddress vitor.souza@inpe.br
%B AGU Fall Meeting
%C Washington, D. C.
%8 10-14 dec.
%K Tripolar BM perturbations across dayside magnetopause exhausts – comparing THEMIS multi-spacecraft observations and PIC simulations.
%X THEMIS occasionally show evidence of tripolar perturbations of the out-of-plane (guide) magnetic field across reconnection exhausts at the dayside magnetopause. This type of guide field signature may indicate a presence of magnetic flux ropes that form between two active reconnection X-lines. We examined the 3-s cadence of THEMIS ion velocity distributions in the field parallel-perpendicular plane across these types of reconnection exhausts. The survey resulted in a clear evidence of two counter-streaming magnetosheath ion populations in at least 30% of tripolar events. The same type of bi-streaming ions were observed when THEMIS A,D,E confirmed a case of converging ion exhausts at the dayside magnetopause. A particle-in-cell (PIC) simulation for asymmetric magnetopause conditions confirm the presence of two counter-streaming ion populations within a magnetic island that formed between two X-lines. The time-dependent ion particle trajectories clearly show how the two ion populations originated in the upstream magnetosheath and reached the same region of two converging exhausts from the two adjacent reconnection X-lines.
%@language en