Abstract. We apply a recently developed dynamic fluid-kinetic (DyFK) model to simulate and investigate the effects of soft auroral electron precipitation and perpendicular ion heating by waves on the plasma outflow along auroral field lines. The DyFK model is constructed by coupling a fluid ionospheric model for the region from 120 to 800 km to a semikinetic treatment for topside through several RE altitude region. This approach, which is described in detail here, allows a partially self-consistent description of the plasma transport along highlatitude flux tubes where both low-altitude ionospheric heating and ionization production and loss as well as high-altitude energization and kinetic effects are incorporated and stressed. In the present work, we investigate the combined effects of the F region plasma production and electron heating by soft auroral electron precipitation and ion perpendicular wave heating at high altitudes, which produces ion conics. The auroral event simulated here involves 1.5 hours of moderate soft electron precipitation and relatively weak ion cyclotron waves along the magnetic field lines. The simulations reveal the F region electron heating and ionization

[1] Ion outflow processes along auroral field lines are simulated with a dynamic fluid kinetic (DyFK) model which couples a comprehensive fluid ionospheric (120-1100 km altitude) model to a semikinetic treatment for the topside through 3 R E region. Using a simplified electron description, large-scale extended parallel electrical fields driven by anisotropic hot plasma distributions have been incorporated in addition to the soft auroral electron precipitation and wave-driven ion-heating processes previously simulated [Wu et al., 1999]. Simulations show that auroral ionospheric ion outflows involve initial evacuation, ion-heating, and replenishment phases. The ionospheric ion supply is effectively elevated by the soft electron precipitation to topside altitudes, where the wave-driven transverse ion heating pumps ions upward. The altitude distribution and duration of wave heating and potential drop largely affect the ''pressure cooker'' ion trap formation. With comparable and persistent downward potential drop and wave heating, the pressure cooker produces slow and dense suprathermal ion outflows. The ion velocity distribution evolves in an extended ion trap from bowl and counterstreaming suprathermal conic distributions at lower altitudes into mirrored conics and finally toroidal distributions at the top of the pressure cooker. The wave heating is less effective for H + ions, owing partly to their fast transit through the wave-heating region. The H + ion trap tends to be lower but more extended in altitudinal extent than the O + ion trap. H + flux and total flow are about a third to half of those of O + . Some of the toroidal distributions and ion species variations of beam and conic energies in these simulations qualitatively resemble satellite observations of such ion distributions.

Solar flares are a major particle accelerator in the solar system (Reames, 2015). In the standard flare model (aka CSHKP model) (Carmichael, 1964;Hirayama, 1974;Kopp & Pneuman, 1976;Sturrock, 1966), magnetic reconnection at the reconnection current sheet powers the particle acceleration process. Recent RHESSI imaging observations (Liu et al., 2013) have revealed that energetic electrons may be accelerated at reconnection exhausts. It is possible that energetic electrons propagating downward and upward undergo different acceleration processes. In the standard flare model, the reconnection is between close field lines so electrons accelerated in the upward propagating reconnection exhaust can not reach 1 AU unless interchange reconnection is involved (Masson et al., 2013) (Note that however, a closed loop from a preceding CME can extend beyond 1 AU. If magnetic reconnection occurs between the two legs of this closed loop, then electrons can propagate into 1 AU along a closed loop). Electrons can be accelerated at these interchange reconnection sites as well. In the early work of Heyvaerts et al. (1977), flares are driven by interchange reconnection alone, without closed field reconnection. One important implication of Heyvaerts et al. (1977)

Abstract. The continuum enhancement, another type of terrestrial nonthermal continuum radiation, has been frequently observed by the Geotail spacecraft. This radiation is a short-lived enhancement generated at the plasmapause from the midnight to dawnside sector. Simultaneous Geotail and Wind observation shows that usual nonthermal continuum radiation (the normal continuum) generated at the dayside plasmapause appears to follow the continuum enhancement. This suggests that both radiations are generated by a series of electrons injected at the midnight sector associated with the same substorm. The continuum enhancement regularly consists of "fast" and "main" components. The fast component has faster rising rate of average frequency (+50,•+100 kHz/h) and shorter duration of 0.5-1 hours. The main component has slower rising rate of average frequency (+10,•+20 kHz/h) and longer duration of 1-3 hours. We suggest that the former is generated by the lower-energy electrons at the midnight plasmapause, while the latter is generated by the higher-energy electrons at the dawnside plasmapause. However, the harmonic structure of the continuum enhancement indicates the radius of the source on the plasmapause close to the magnetic equatorial plane. We find thag the radius of the plasmapause first reduces at the rate of-1.0 ,• -0.5 RE/h in the first 1 hour after the substorm onset. This shows a typical scale of the peeling off of plasma from the outer plasmasphere associated with individual substorms. When geomagnetic activity is low we also find the reversal expansion of the plasmapause at the rate of +0.1 ,• +0.5 RE/h in the next 1 hour. The expansion rate is faster than the value expected from the upwelling from the upper ionosphere. This suggests that fast compression and recovery processes should also affect the radial motion of the plasmapause.