Team 81

The effect of ULF turbulence and flow chaotization

on plasma energy and mass transfer at the magnetopause

Expected outputs and schedule of the project

Two sessions of one week each at ISSI are planned: the first one has taken place in October 2005 (from 17th to 21st, week 42), and the second one will probably be in July of 2006.

Different approaches to the given questions are necessary, using numerical simulations, experimental data and theoretical predictions. As the team joins all these skills, the main outcomes of this group are likely to come from the confrontation of these different approaches. The work will therefore be organized as follows:

1. Before the first week (by mail): Establish a list of precise items in the global subject, and determine which approaches must be implemented for each topic

2a. First week: Present review papers and contributions on these items

2b. First week (Cont^d): General discussion to restrict the list of items to a very limited number

2c. First week (Cont^d): Discussions by small sub-groups to define more precisely the work on each item and initiating it. Final general discussion in order that all the specific studies really become parts of an ensemble program.

5. Between the two weeks (by mail): Distant work of all the sub-groups on the selected items,

6. Second week: Presentation of the results, discussion and complementary work. Preparation of the drafts of the papers that should follow.

Questions that will be adressed by the group as decided during first meeting:

1: Magnetic patterns: magnetic holes, mirror structures

TP, EK, PH, VG, CJ, RT, EL, OP, GB, FS, SPS, EA (meaning of initials)

Experiment:

• •Analysis of the coherence of mirror structures, surrogate method, bicoherence GB, FS
• •Statistics : condition of occurrence of mirror modes and of diamagnetic structures. Amplitude of mirror modes with respect to distance to the magnetopause or the cusp, or with respect to propagation along the flow VG, FS, EL, EA
• •Where are the small scales with respect to the mirror structures (edges of structures or turbulence everywhere), intermittency GB
• •Possibility of getting distribution functions of ions inside a mirror structure VG, EA. •Interaction of mirror modes with the magnetopause: use of spacecraft with large separation SPS

Numerics:

• •Interaction of mirror modes with magnetopause PH •
• Comparison of PIC code with hybrid code, role of electron dynamics CJ, VG, PH

Theory:

• •Understanding and explaining of the basic physics of mirror mode GB, RT, OP, FS •
• Evolution of mirror mode in Landau fluid theory TP, EK

Combination of different approaches:

• •Comparison of k spectra obtained by simulations, theory, experiments FS, TP, EK, PH •
• Comparison of Landau fluid theory with hybrid simulations TP, EK, PH

2 : Turbulence (ULF/ELF) at the magnetopause and reconnection

LR, MM, YK, FS, GB, PH

Experiments: LR, FS, YK, SPS

• •Case study of magnetopause crossings where reconnection is observed, ELF study inside the boundary, ULF in front •
• Large scale correlations between turbulence in the magnetosheath and reconnection
  

Numerics

• •Interaction of mirror modes with magnetopause PH

3: Plasma structuring and penetration across the magnetopause

EK, GB, MM, CJ, SPS, EA

Experiments:

• •Basic physics of jets, analysis of possible generation mechanisms
• •Statistics of jets, how common are they ? main properties, dimensions, velocities, direction with respect to shock and magnetopause. Link between Alfvenic collapse and jet generation
• •Jets at the magnetopause, relation with reconnection, influence on balance at the magnetopause
• •Fine structure of current layer

Theory:

• •Modeling of jets with Hall-MHD or high beta MHD
• •Modeling of the structure of the magnetopause: current sheets, geometry, Hall effects (PIC code) CJ, VG
  
• •Influence of the heat flux on the behaviour of rotational discontinuities, role of closure equations GB

Initials of contributors :

Gérard Belmont, GB Elisabeth Lucek, EL Vincent Génot, VG Evgueni Kuznetsov, EK Serguei Savin, SPS Youri Khotyaintsev, YK Peter Hellinger, PH Ermanno Amata, EA

Fouad Sahraoui, FS Claus Jaroschek, CJ Thierry Passot, TP Milan Maksimovic, MM Laurence Rezeau, LR (Oleg Pokhotelov, OP Rudolf Treumann, RT)

update 21/10/2005 L. Rezeau