1. A.Vaivads, B. N. Rogers, M. André, S. Buchert, N. Cornilleau-Wehrlin, A. Eriksson, A. Fazakerley, Y. Khotyaintsev, A. Lahiff, B. Lavraud, T. Phan Cluster Workshop VI, 1-3 October, 2003 ESTEC Narrow current sheets and lower hybrid turublence at the magnetopause

2. Swedish Institute of Space Physics Uppsala Cluster Workshop VI 1-3 October 2003 slide 2 Cluster and magnetopause scales Intro Cluster MP crossing E~jxB Separatrix Waves Summary

3. Swedish Institute of Space Physics Uppsala Cluster Workshop VI 1-3 October 2003 slide 3 Small scales and waves, what we want to know? Structure? sheet vs tube local vs global dispersion relation Transport plasma energy (particles, Poynting flux) Momentum equation Generalized Ohm’s law free energy Energy conversion j·E Intro Cluster MP crossing E~jxB Separatrix Waves Summary

4. Swedish Institute of Space Physics Uppsala Cluster Workshop VI 1-3 October 2003 slide 4 Density dip ~1c/  pi Narrow current sheet (yellow) 5-10 e,  e Strongest E fields within the current sheet Differences among s/c in E and B. Intro Cluster MP crossing E~jxB Separatrix Waves Summary

5. Swedish Institute of Space Physics Uppsala Cluster Workshop VI 1-3 October 2003 slide 5 Intro Cluster MP crossing E~jxB Separatrix Waves Summary

6. Swedish Institute of Space Physics Uppsala Cluster Workshop VI 1-3 October 2003 slide 6 Intro Cluster MP crossing E~jxB Separatrix Waves Summary

7. Swedish Institute of Space Physics Uppsala Cluster Workshop VI 1-3 October 2003 slide 7 Generalized Ohms law and Cluster Spin resolution, ion scales ● B, E, n, p e, u i, u e, j High time resolution, small scales ● B, E, n (f pe ) ● n (satellite potential), p e, j (curlometer, 1 s/c methods) u i, u e Intro Cluster MP crossing E~jxB Separatrix Waves Summary

8. Swedish Institute of Space Physics Uppsala Cluster Workshop VI 1-3 October 2003 slide 8 E~j x B, all 4 s/c Potential drop across the current sheet of a few 100 V Intro Cluster MP crossing E~jxB Separatrix Waves Summary

9. Swedish Institute of Space Physics Uppsala Cluster Workshop VI 1-3 October 2003 slide 9 5-10 e,  e current sheet, j perp and j II B and n gradients coincides E~j x B  p e not important e- beam carrying j II can generate waves Intro Cluster MP crossing E~jxB Separatrix Waves Summary

10. Swedish Institute of Space Physics Uppsala Cluster Workshop VI 1-3 October 2003 slide 10 Generalized Ohms law and Cluster Spin resolution, ion scales ● B, E, n, p e, u i, u e, j High time resolution, small scales ● B, E, n (f pe ) ● n (satellite potential), p e, j (curlometer, 1 s/c methods) u i, u e Intro Cluster MP crossing E~jxB Separatrix Waves Summary

11. Swedish Institute of Space Physics Uppsala Cluster Workshop VI 1-3 October 2003 slide 11 Reconnection in 2-fluid 2D MHD, Ey Reconnection with a guide field Width of separatrix is a few c/  pe E is strong along the separatrix E ~j x B along separatrix d y p e small [Rogers] Intro Cluster MP crossing E~jxB Separatrix Waves Summary

12. Swedish Institute of Space Physics Uppsala Cluster Workshop VI 1-3 October 2003 slide 12 Intro Cluster MP crossing E~jxB Separatrix Waves Summary

13. Swedish Institute of Space Physics Uppsala Cluster Workshop VI 1-3 October 2003 slide 13 Waves strongest in the narrow current sheet (gradient in n and B) Broad band Spectral peaks f~f LH Spectral peaks f~100 Hz, ’whistlers’ Poynting flux associated to both ’whistlers’ and ’LHD’ Waves generated by gradients or electron beams? E B S E n  S S Intro Cluster MP crossing E~jxB Separatrix Waves Summary

14. Swedish Institute of Space Physics Uppsala Cluster Workshop VI 1-3 October 2003 slide 14 15-35 Hz band-pass filter (LH) k  e ~1 low coherence wave transports e- across the current sheet. D  10 -9 m 2 /s, Diffusion? Intro Cluster MP crossing E~jxB Separatrix Waves Summary

15. Swedish Institute of Space Physics Uppsala Cluster Workshop VI 1-3 October 2003 slide 15 Strongest E (10s mV/m) within narrow current sheets ~10 c/  pe on magnetospheric side of MP E~jxB,  p e is not important Separatrix of reconnection Other explanations? Strong lower hybrid drift waves and whistlers Electron transport due to LHD waves can be important only within the current sheet D  10 9 m 2 /s, diffusion? Summary Intro Cluster MP crossing E~jxB Separatrix Waves Summary