1. Xin LiuMOP 20111 The growth of plasma convection in Saturn’s inner magnetosphere X. Liu; T. W. Hill; R. A. Wolf; Y. Chen Physics & Astronomy Department, Rice University, Houston, TX

2. Xin LiuMOP 20112 Outline Rice Convection Model (RCM) 3 plasma source models Simulation results comparison with observations

3. Xin LiuMOP 20113 Magnetosphere Ionosphere Coupling The Rice Convection Model (RCM) Described by Liu et al. [JGR, doi:10.1029/2010JA015859]

4. Xin LiuMOP 20114 Saturn’s inner magnetosphere: 2<L<12 Modeling region: 2<L<40 (Boundary condition: L=2: ; L=40: ) Ionospheric conductance:  P = constant,  H = 0 Inner plasma source models: J06 = [Johnson et al., Ap. J., 2006] S10 E3 = [Smith et al., JGR, 2010, doi:10.1029/2009JA015184 ], “E3” version. CJ10 = [Cassidy & Johnson, Icarus, 2010, doi:10.1016/j.icarus.2010.04.010 ] RCM setup

5. Xin LiuMOP 20115 S10 E3 150 kg/s CJ10 160 kg/s J06 24 kg/s Comparison of 3 source models Mass loading rate Locations of charge-exchange /ionization cross-over, and of ionization peak.

6. Xin LiuMOP 20116 Comparison of 3 source models (Ionization rate only) S10 E3 150 kg/s CJ10 160 kg/s J06 24 kg/s

7. Xin LiuMOP 20117 Simulation results of J06 model

8. Xin LiuMOP 20118 Convection pattern at quasi steady state Slow, wide and dense outflow channels alternating with fast, narrow and tenuous inflow channels.

9. Xin LiuMOP 20119 Mass flux of J06 model

10. Xin LiuMOP 201110 Inflow longitudinal width ratio of J06 model [Observation data from Yi et al., JGR, 2010]

11. Xin LiuMOP 201111 Inflow and outflow channel velocities of J06 model [Observation data from Yi et al., JGR, 2010]

12. Xin LiuMOP 201112 Recall the mass loading rates of 3 source models J06 = 24 kg/s S10 E3 = 150 kg/s CJ10 = 160 kg/s What about scaling J06 model up to 150 kg/s mass loading rate? (Also scaling up  P with the same ratio to confine the radial velocities)

13. Xin LiuMOP 201113 Model: J06 Global ionization: 24 kg/s Pedersen conductance: 0.3 S Model: J06*150/24 Global ionization: 150 kg/s Pedersen conductance: 0.3*150/24 S Mass flux Outflow velocity Inflow velocity Inflow width ratio Scale up

14. Xin LiuMOP 201114 Model: S10 E3 Global ionization: 150 kg/s Pedersen conductance: 0.3*150/24 S Mass fluxOutflow velocityInflow velocityInflow width ratio

15. Xin LiuMOP 201115 Model: CJ10 Global ionization: 160 kg/s Pedersen conductance: 0.3*160/24 S Mass fluxOutflow velocityInflow velocityInflow width ratio

16. Xin LiuMOP 201116 Conclusions The radial distribution of plasma source plays a key role in plasma convection pattern. The higher plasma mass loading rate can be compensated by higher ionospheric Pedersen conductance. Simulations with more recent plasma source models are different from simulation with Johnson’s 06 model, and in disagreement with CAPS observations in some aspects.

17. Xin LiuMOP 201117 Thank you

18. Xin LiuMOP 201118 Supporting material

19. Xin LiuMOP 201119 Observed result of corotation lag Simulated result of corotation lag Corotation lag of J06 model

20. Xin LiuMOP 201120 Longitudinal width and radial velocity Faraday’s law for steady state: and w is the longitudinal width

21. Xin LiuMOP 201121 Test particles tracking of J06 model