M. Yamauchi 1 , I. Dandouras 2 , H. R e me 2 , Y. Ebihara 3

1. Fate of cold ions in the inner magnetosphere: energization and drift inferred from morphology and mass dependence M. Yamauchi1, I. Dandouras2, H. Reme2, Y. Ebihara3 (1) Swedish Institute of Space Physics (IRF), Kiruna, Sweden (2) CNRS and U. Toulouse, IRAP, Toulouse, France (3) Kyoto University, Uji, Japan Geospace2014@Rhodos, 2014-9-17

2. a zoo of various patterns North-south symmetry of trapped particle motion for fixed MLT ⇒ inbound-outbound asymmetry = temporal change of 1-2 hour

3. Cluster Statistics Decay in time partly came from rapid degradation of the sensor

4. (a) Vertical stripes: Nearly vertical in the spectrogram, extending from the about 10 keV to sub-keV (dispersion is very weak). Only found near midnight during substorms. Mostly inbound-outbound asymmetric (life time~1h), indicating substorm injection. (b) Wedge-like energy-latitude dispersed sub-keV ions: Stronger dispersion than (a), at slightly lower energy (up to few keV). Often found in the morning to noon sectors some hours after a substorm.Often inbound-outbound asymmetric, but can yet be explained by ion drift (next figure) of <0.1 keV ion source. (c) Short bursts of low-energy ions: a peak energy flux less than 100 eV but not thermal. Found all local time without clear relation to geomagnetic activities. Often inbound-outbound asymmetric (life time~1h), indicating a local phenomena. (d) Warm trapped ions confined near equator: tens eV to a few hundred eV without dispersion.Found all local time without clear relation to geomagnetic activities. Comparison to different SC indicates life time~1h, indicating a local phenomena.

5. Comparison of observation and ion drift simulation. 0.1 keV t ≈ 6 hr t ≈ 4 hr Cool source (<0.1 keV, but not cold) can cause wedge-like dispersed sub-keV ions with its inbound-outbound asymmetry even at noon, and hot source can cause ion band (keV). Due to different drift velocity, two population has different O/H ratio.

6. Next:O+/H+ and He+/H+ differences 2001-2006 (~300 relatively clean data out of ~760 traversals) (a) Vertical stripes types (a)-(c) Appearances of H+, He+, and O+ are not correlated

7. (b) Wedge-like energy-latitude dispersed ions Timing & energy are quite different among H+, He+, and O+ (drift theory predicts same energy-time diagram for all species).

8. (c) Short bursts of low-energy ions: (d) Warm trapped ions confined near equator Unlike most H+ bursts, He+ bursts (time scale~1h) are in perpendicular direction. It is also independent from O+, indicating local heating of He+ only. Equatorially-confined hot ions sometime show E(H+) < E(He+) while majority is E(H+) = E(He+).

9. Conclusions & Future Observations • There must be filtering mechanisms that select only cold He+ and separates them from H+ and O+ for both energization and transportation. • We need more investigation on Mass dependency  Nitrogen Ion TRacing Observatory (NITRO) for next ESA's M-class call Sprinter meeting: Saturday 11:30-16:00 (after coffee break)

10. 3-spacecraft mission (high inclination) Daughter (gradient) North In-situ (spinning) Imaging (3-axis) & monitoring Cold ion mass spectrometer Hot ion (3~4 different types) Energetic ions Photoelectron Magnetometer+Waves (ΩN) Langmuir Probe (plus alpha) FOV UV/visible (narrow FOV) IR (narrow FOV) Cold ion mass spectrometer Hot ion mass analyser Photolectron Magnetometer Langmuir Probe (plus alpha) South In-situ spacecraft start with 6-7 Re apogee outside the radiation belts during the first 2 years, and then gradually decrease the apogee altitude to explorer the “dangerous” region. Monitoring satellite flies just above the polar ionosphere at altitude ~2000 km.

11. Payloads In-situ #1 mother (spinning) * Mass spectrometer (cold) (Bern) * Ion analyzers (0.03 – 30 keV): (1) Narrow mass range (Kiruna) (2) Wide mass range (Toulouse) (3) No mass (LPP) (4) low G-factor mass (Japan) * Ion mass analyzer (> 30 keV)(UNH) * Electron (photoelectron)(London) * Magnetometer(Graz) * Waves (ΩN≠ΩO) (Prague) * Langmuir Probe (Brussels) * ENA monitoring substorm (Berkeley) * (Potential Control=SC subsystem) Remote sensing & monitoring (3-axis) * Optical (emission) (LATMOS & Japan) (1) N+: 91 nm, 108 nm (2) N2+: 391 nm, 428 nm (3) NO+: 123-190 nm, 4.3 µm (4) O+: 83 nm, 732/733 nm * Mass spectrometer (cold)(Goddard) * Ion analyzer (< 0.1 keV) (Kirina) * Electron (photoelectron)(London) * Langmuir Probe(Brussels) * Ionospheric sounder (Iowa) * Magnetometer (Graz/UCLA) * Waves (ΩN≠ΩO) (Prague) * Ionospheric optical emission (???) * underline: core, * colored: important, * black: optional Possible methods for ion analyzers: Magnet, Magnet-TOF, reflection-TOF, MCP-MCP TOF, shutter-TOF Optical imager needs a scanner keep in-situ spacecraft within FOV.

12. End Yamauchi, et al. (2012), GRL, doi:10.1029/2012GL052366. Yamauchi, et al. (2013), AnnGeo, doi:10.5194/angeo-31-1569-2013. Yamauchi, et al. (2014), AnnGeo, doi:10.5194/angeo-32-83-2014. Yamauchi, et al. (2014), JGR, doi:10.1002/2013JA019724.

13. Next:O+/H+ and He+/H+ differences 2001-2006 (~300 relatively clean data out of ~760 traversals) (a) Vertical stripes types (a)-(c) Appearances of H+, He+, and O+ are not correlated

14. (b) Wedge-like energy-latitude dispersed ions p/a < 45° p/a ≈ 90° cf. drift theory predicts same energy-time diagram for all species

15. (c) Short bursts of low-energy ions: Unlike majority of H+ bursts, He+ bursts are mostly in perpendicular direction and time scale ~ 1h. Even independent from O+, indicating local heating of He+ only.

16. (d) Warm trapped ions confined near equator Equatorially-confined hot ions sometime show E(H+) < E(He+) while majority is E(H+) = E(He+). He+ is certainly heated e.g. by He cyclotron waves (1980’s) equator