The TRIO-CINEMA mission Tr iplet I onospheric O bservatory – C ubesat

1. The TRIO-CINEMA mission Triplet Ionospheric Observatory –Cubesat for Ion, Neutral, Electron, and Magnetic fields R. P. Lin1, Dong-Hun Lee & the TRIO-CINEMA team School of Space Research, Kyung Hee Univ. 1also Physics Dept & Space Sciences Laboratory Univ. of California, Berkeley

2. Solar Wind Electrons Core => solar wind thermal plasma electrons Halo/Strahl=> heat flux from ~106 K corona Superhalo => from coronal heating or solar wind acceleration process? interplanetary acceleration?

3. Wind Electron Electrostatic Analyzer High EESA-H) STEREO STE (SupraThermal Electron ) Detector STEs on STEREO A & B (launched Oct. 2006) are the first silicon semiconductor detectors in space to detect electrons & ions in situ, and energetic neutrals atoms (ENAs) & X-rays (for remote sensing) down to ~2 keV.

4. Quiet-time interplanetary electrons IMPACT/STE observations (1-day average) Super-halo electrons: isotropic power-law spectrum

5. Upstream ions measured by STEREO STE sensor(courtesy M. Pulupa)

6. STE X-ray Observations: SCO X-1 (Hsieh et al 2009)

7. * Charge exchange • - Energetic (suprathermal) ions: 1-100 keV • - Cold hydrogen(H) geocorona: 1000 K ~ 0.1 eV • t = 1 Re / v (1 keV) ~ 15 s • proton (> keV) H-atom (< eV) • proton (< eV) H-atom (> keV) “ENA” • becomes less than a few 0.1 eV • No effective changes in both energy and direction between the initial ion and ENA for 25 keV at r=3.5 Re, t ~ 7 hrs!

8. * ENA observations Williams et al., Rev. Geophys., 1992

11. 2006 November 6 Terrestrial ENA observations(Wang et al, 2009)

12. Average particle energy spectra

13. STEREO STE ENA fluxes vs. Time (Courtesy L. Wang)

14. JHU/APL ENA models (Roelof & Skinner, 2000) *Azimuthal dependency: *Pitch-angle dependency: (Gruntman, 1997) *L-shell dependency : fL (~3-10, fixed) Free parameters: k1 , Φ1 , kα, nα Best-fit: k1 =1.0, Φ1 =177° kα=3.0, nα=4.7

15. JHU/APL ENA model fits (Courtesy L. Wang)

16. These are the first ENA measurements below 26 keV from low Earth orbit, and the first of a weak substorm injection. STE is much more sensitive than previous ENA sensors, especially below ~20-30 keV. STE measures all energies simultaneously (no electrostatic analyzer energy sweep) STE is insensitive to geocoronal EUV (micro-channel plates require rejection of EUV by ~10-5, reducing ENA effective area by factor of ~20) STE has excellent energy resolution (~1 keV FWHM)

17. STEIN (SupraThermal Electron, Ion, Neutral) sensor Energy range: ~2-300 keV Resolution: ~ 1keV FWHM Field of view ~15º x70º

18. CINEMA (Cubesat for Ions, Neutrals, Electrons, MAgnetic fields)

19. MAGIC (MAGnetometer Imperial College) using Anisotropic Magnetoresistive (MR) sensors Collaborators: T. Horbury, P. Brown ICL

20. * A triplet of identical cubesats will be built to carry out the following scientific objectives: • multi-observations of ionospheric ENA (Energetic Neutral Atom) imaging, • ii) ionospheric signature of suprathermal electrons and ions associated with auroral acceleration as well as electron microbursts, • iii) magnetic fields. * Each satellite, a cubesat for ion, neutral, electron, and magnetic fields (CINEMA), is equipped with a suprathermal electron, ion, neutral (STEIN) instrument and a 3-axis magnetometer of magnetoresistive sensors.

21. * TRIO is developed by three institutes: • one CINEMA by UCB under the NSF program, • two CINEMA by KHU under the WCU program, • iii) three magnetometers by Imperial College. Planned Launch around late 2011 • * Multi-spacecraft TRIO observations will provide: • stereo ENA imaging with a wide angle in LT, which are sensitive to the evolution of ring current phase space distributions, • suprathermal electron measurements with narrow spacings, which reveal the differential signature of accelerated electrons driven by Alfven waves and/or double layer formation in the ionosphere between the acceleration region and the aurora, • suprathermal ion precipitation/upflow when the storm-time ring current appears. In addition, multi-spacecraft magnetic field measurements in low earth orbits will allow the tracking of the phase fronts of ULF waves, FTEs, and quasi-periodic reconnection events between ground-based magnetometer data and upstream satellite data.

22. Storm time particle precipitation (courtesy Jae-Jin Lee) Oct 13, 2004 Trapped electrons ExB drift Precipitating electrons Korean STSAT-1 - SSL, Berkeley -

23. Multi-satellite Observation (courtesy Jae-Jin Lee) - Spatial or Time Variation - Separation Speed: 1m/min 1 d: 1.4 km 10 d: 14 km 1 m: 42 km 1y: 504 km 10 km d Is it local acceleration?

24. Electron Microbursts 1 Second Electron microburst observed by Korean STSAT-1(courtesy Jae-Jin Lee)

25. CINEMA measurements

26. Collaboration with THEMIS(courtesy Jae-Jin Lee) - Ground Observation - - Multi satellite Observation - We need low earth orbit satellite observations to connect ground observations and multi satellite observations of THEMIS mission.

27. Collaboration with Radiation Belt Storm Probes (2 Spacecraft)(planned launch 2012)

28. M. C. Fok, http://mcf.gsfc.nasa.gov/Moon

29. Neutral Hydrogen Estimated fluxes ENAs originating from protons in the Earth’s Plasma Sheet

30. Mewaldt et al, 2009