Space Plasma Physics and Magnetometry Group O. Marghitu, M. Echim, H. Comi ş el,

1. Space Plasma Physics and Magnetometry Group O. Marghitu, M. Echim,H. Comişel, O.D. Constantinescu, A. Blăgău,C. Bunescu, M. Ciobanu National Institute for Lasers Plasma and Radiation Physics Institute for Space Sciences July 6, 2004 Background: The terrestrial magnetosphere

2. Outline • Goals • Scientific themes • Main achievements • Selection of scientific results

3. Contribution to the scientific processing of the data collected by the space missions: CLUSTER — sci.esa.int/cluster INTERBALL — www.iki.rssi.ru/interball FAST — plasma2.ssl.berkeley.edu/fast EQUATOR-S — www.mpe.mpg.de/EQS A Goals A 2. Theoretical investigation of the solar wind – magnetosphere – ionosphere system. 3. Preparation for ESA (PECS, PRODEX, …), EU (FP6, …), and NASA (… ?) programs.

4. B Scientific Themes B • Methods to derive the satellite attitude based on magnetic field data and dynamical modeling – MAGION 2, 3, 4 & 5 data • Auroral plasma physics: Arc electrodynamics, magnetosphere – ionosphere coupling – FAST and CLUSTER data • Theoretical and experimental investigation of the magnetic mirror instability – EQUATOR-S and CLUSTER data • Fundamental dynamics of space plasma: Plasma transfer at the terrestrial magnetopause – INTERBALL and CLUSTER data

5. B Methods to Derive theSatellite AttitudeB • Romanian involvement in space magnetometry experiments dates back to 1976 – 1981, when the instruments SG-R1, SG-R2, and SG-R3 were flown on the Intercosmos satellites IK-18, IK-20, and IK-21. • More recently, Romanian mag.meters were flown on several Czech sub-satellites: MAGION-2 (AKTIVNII, 1989), MAGION-3 (APEX, 1991), MAGION-4 (INTERBALL-TAIL, 1995), and MAGION-5 (INTERBALL-AURORA, 1996). • An essential task of the magnetometers: to provide information to be used for deriving the satellite attitude. MAGION-5 PI Institute: IAP Prague Launch: August 29, 1996 Orbit: 20000 x 1000, 650 Lost shortly after launch and recovered in May 1998. http://www.ufa.cas.cz/html/magion/magion.html

6. MAGION-5 trajectory (50 orbits) Attitude parametrization: Euler transf. B Methods to Derive theSatellite AttitudeB • Use magnetic field data and additional information produced by specialized sensors (Sun, Earth). • When the additional information is degraded special numerical methods are required. • By using magnetic field data and the dynamic modeling of the satellite motion it was possible to find the attitude of MAGION 2, 3 & 5, although the additional information was limited. • Potential to extend the method to other missions (Double Star ?)

7. Ground optical equipment • Low light CCD camera developed at MPE. • Images conjugated with FAST during an auroral campaign in Jan. – Feb. 1997. • Location: Deadhorse, Alaska (Lat. 70.220, Lon. 211.610). • Photo courtesy W. Lieb Images 4s apart taken during the FAST overpass. The satellite is indicated as a square. ’11’ and ’22’ show the edges of the first two ion beams, as read in the ion spectrograms. North is at the left and East at the bottom. DC electromagnetic field and particle data. From top to bottom: magnetic field perturbation (a);energy and pitch-angle spectrograms for electrons / ions (b, c) / (d, e); potential drop alongthe satellite trajectory (f). • FAST • PI Institute: UCB-SSL • Launch: August 21, 1996 • Orbit: 4000 x 400, 830 • http://plasma2.ssl.berkeley.edu/fast/ B Auroral Plasma Physics: Arc Electrodynamics B • Work done in collaboration with Max-Planck-Institut für extraterrestrische Physik, Garching,Germany, and Space Sciences Lab., Univ. of California, Berkeley, US. • In order to evaluate the deviation of a real arc from the ideal model we developed the ALADYN (AuroraL Arc electroDYNamics) method, based on a parametric model of the arc and able to accommodate experimental data input. • ALADYN was illustrated with in-situ data measured by Fast Auroral SnapshoT Explorer (FAST) and ground optical data measured by a CCD camera developed at MPE.

8. B Auroral Plasma Physics: M – I Coupling B • Work in progress, in collaboration with the Physics Department of the Umeå University, Sweden, MPE, and UCB-SSL. • Focus on potential arc generator region, by using conjugated FAST and CLUSTER data (at 4000km and 100000km altitude, respectively). • CLUSTER • ESA mission consisting of 4 identical s/c, each of them equipped with 11 identical instruments. • Launched in July – August 2000, after a failed start in June 1996. • The tetrahedron configuration allows the derivation of the current density vector, J. • By using electric field, E, information from several instruments it is possible to improve on the reliability of E in the arc generator region • The energy density, E•J, inferred from CLUSTER data, can be compared with the electron energy flux derived from FAST data.

9. Experimental data vs. fit • Fit on data from C1 and C2 • C3 and C4 are witness s/c • MM– theoretical model • Multi-layer structure • Central ‘unit’ = ‘classical’ MM B Magnetic Mirror InstabilityB • Work in collaboration with Institut für Geophysik und extraterrestrische Physik, Braunschweig, Germania. • The magnetic mirror (MM) instability is common in the Earth magnetosheath but also in other space plasmas. • A model was built which describe the 3D geometry of the MM; the model predicts a complex geometrical structure, depending mainly on the plasma anisotropy and βparameter. • By using measured magnetic field data one can derive the model parameters. • Multi-satellite data, as those provided by CLUSTER, improve on the reliability of the fit results.

10. Micro-scale processes at the magnetopause. Penetration of a plasmoid into the magnetosphere. B Plasma Transfer at the Terrestrial MagnetopauseB • Work in collaboration with Belgian Institute for Space Aeronomy, Bruxelles • One of the addressed topics: Investigation of the role of collective processes in the propagation of a solar wind plasma inhomogeneity (plasmoid). • Decoupling of the plasma motion from the “motion” of the magnetic field lines, because of the electric field parallel to the magnetic field. • The differential drift of ions and electrons results in space charges and a polarization electric field which supports the plasmoid convection.

11. C Main AchievementsC • Investigation of fundamental processes in space plasma, that cannot be replicated under laboratory conditions. • Participation in the scientific processing and interpretation of data obtained in the frame of the international program IASTP (Inter-Agency SolarTerrestrial Program). • Access to state-of-the-art hardware and software. Expertise in numerical methods related to space applications and space plasma simulations. • Consolidation of an efficient research group, at a time when the space information becomes more and more part of the daily life (space weather). • Successful international collaborations: • Max-Planck-Institut für extraterrestrische Physik, Garching,Germany • Belgian Institute for Space Aeronomy, Bruxelles, Belgium • Institute of Atmospheric Physics, Prague, Czech Republic • Institute of Experimental Physics, Košice, Slovakia • Institut für Geophysik und extraterrestrische Physik, Braunschweig, Germany • Physics Department, University of Umeå, Sweden • Space Sciences Lab., Univ. of California, Berkeley, US

12. D Scientific ResultsD • Papers in referred journals and proceedings: • M. Ciobanu, et al., The SGR-6,7,8 fluxgate magnetometers for MAGION-2, 3, 4 and 5 small satellites, in: Small satellites for Earth observation, Berlin, 1997 • H. Comisel, et al., Attitude estimation of a near Earth satellite, Acta Astron., 40, 781-788, 1997 • M. Echim, et al., Multiple current sheets in the double auroral oval observed from the MAGION-2 and MAGION-3 satellites, Ann. Geophys., 15, 412-427, 1997 • M. Echim, et al., The early stage of a storm recovery phase – a case study, Adv. Space Res., 20, 481-486, 1997 • H. Comisel, et al., Magion-3 spacecraft attitude from dynamics and measurement, BalkanPhys. Lett., 6, 59-64, 1998 • M. Echim and J. Lemaire, Laboratory and numerical experiments of the impulsive penetration mechanism, Space Sci. Rev., 95, 565-601, 2000

13. D Scientific ResultsD • Papers in referred journals and proceedings: • O. Marghitu, et al., Observational evidence for a potential relationship between visible auroral arcs and ion beams, Phys. Chem. Earth, 26, 223-228, 2001 • O.D. Constantinescu, Self-consistent model of mirror structures, J. Atm. Sol.-Terr. Phys., 64, 645-649, 2002 • M. Echim and J. Lemaire, Advances in the kinetic treatment of the solar wind magnetosphere interaction: the impulsive penetration mechanism, in: Geophysical Monograph 133, eds. P. Newell si T. Onsager, p. 169-179, AGU, Washington, 2002 • M. Echim, Test-particle trajectories in ''sheared'' stationary field: Newton-Lorenz and first order drift numerical simulations, Cosmic Research, 40, 534-547, 2002 • M. Echim and J. Lemaire, Positive density gradients at the magnetopause: interpretation in the framework of the impulsive penetration mechanism, J. Atm. Sol.-Terr. Phys., 64, 2019-2028, 2002 • O.D. Constantinescu, et al., Magnetic mirrors observed by Cluster in the magnetosheath, Geophys. Res. Lett., 30, 1802-1805, 2003

14. D Scientific ResultsD • Ph.D. Theses: • O. Marghitu, Auroral arc electrodynamics with FAST satellite and optical data, Naturwissenschaftliche Fakultät der Technischen Universität Carolo-Wilhelmina, Braunschweig, Germany, Mai 2003, http://www.biblio.tu-bs.de/ediss/data/20030606a/20030606a.html. Published alsoas MPE Report 284, ISSN 0178-0719. • M. Echim, Kinetic aspects of the impulsive penetration of solar wind plasma elements into the Earth´s magnetosphere, Université catholique de Louvain, Belgia, July 2004. • A. Blăgău – work in progress at Max-Planck-Institut für extraterrestrische Physik, Garching , Germany. • 4. O.D. Constantinescu – work in progress at Institut für Geophysik und extraterrestrische Physik, Braunschweig,Germany.

15. D Scientific ResultsD Presentations at international conferences: 1. M. Ciobanu, H. Comişel, et al., Magnetic field data bases: Magion 2, 3, 4 & 5 satellites, COSPAR ColloquiumInterball and beyond, Sofia, February 2002 2. M. Echim, The penetrability of the magnetopause tested by numerical integration of single particleorbits, COSPAR ColloquiumInterball and beyond, Sofia, February 2002 3. O.D. Constantinescu, et al., Modeling the structure of magnetic mirrors using Cluster data, AGUFall Meeting, San Francisco, Decembrie 2002 4.M. Echim, Cross-field propagation of plasma irregularities: numerical results relevant for magnetopause investigation, Int. Conf. on Auroral Phenomena and Solar-Terrestrial Relations,Moscow, February 2003 5. O. Marghitu, et al., A new method to investigate arc electrodynamics, EGS–AGU Joint Assembly, Nice, April 2003 6. O. Marghitu, et al., 3D current topology in the vicinity of an evening evening arc, EGS–AGUJointAssembly, Nice, April 2003 7. O. Marghitu, A. Blăgău, et al., FAST – CLUSTER conjunctions above the auroral oval, STAMMS Conference, Orleans, Mai 2003

16. D Scientific ResultsD Presentations at international conferences: 8. O.D. Constantinescu, et al., Magnetic mirror geometry Uusing Cluster data: case study, STAMMS Conference, Orleans, Mai 2003 9. O.D. Constantinescu, et al., Magnetic mirror geometry Uusing Cluster data: model andcorrelation technique, IUGG General Assembly, Sapporo, July 2003 10. H. Comişel, M. Ciobanu, A. Blăgău, et al., Attitude determination for Magion 5 satellite usingmagnetometer data only, Int. Conf. on Magnetospheric Response to Solar Activity, Praga, September 2003 11. O. Marghitu, CLUSTER moments: Error analysis, CIS Workshop, Paris, September 2003 12. O. Marghitu, M. Hamrin, et al., CLUSTER electric field measurements in the magnetotail, EGU General Assembly, Nice, April 2004 13. M. Hamrin, O. Marghitu, et al., Energy transferin the auroral magnnetosphere as derived from CLUSTER and FAST data, EGU General Assembly, Nice, April 2004 14. O.D. Constantinescu, at al., Particle kinetics and distribution function inside magnetic mirrors, EGU General Assembly, Nice, April 2004