1. ARIES-ACT1 preliminary plasma description C. Kessel, PPPL ARIES Project Meeting, October 13, 2011

2. Systems configuration to detailed configuration (JSOLVER equilibrium) SystemsDetailedARIES-AT R, m5.5 5.2 I P, MA10.610.012.8 βNβN 4.54.835.45 B T, T5.5 5.86 n/n Gr 0.950.871.0 n(0)/ v 1.31.371.35 T(0), keV26.826.431.2 v, keV16.615.9 I BS, MA9.548.3511.65 I CD, MA (on,off- axis) 1.061.3 (0.38, 0.95)1.28

3. Free-boundary equilibrium Converging on profiles between free and fixed boundary equilibria If other other values of δ, ς o,I are found to be good for stability we can modify Using coil set like ARIES-AT, will optimize coil locations later κ x = 2.21 δ x = 0.77 ς o,I = 0 li(1) = 0.54 β N = 4.77 q 95 = 3.53 control point

4. Fixed boundary equilibria, preliminary operating point Mismatch of inner flux surfaces is from profile differences total j toroidal self-driven j toroidal Alignment of boundaries is very good.

5. Fixed boundary equilibria, preliminary operating point, cont’d Pedestal in pressure, T, n bootstrap current IC or EC on-axis current LH off-axis current n = n e +Σn i Ip = 10 MA κ = 2.15 δ = 0.7 ς o,I = 0 q(0) = 3.25 q min = 2.3 β N = 4.83 Li(1) = 0.49 p(0)/ = 2.06 T(0)/ = 1.66 n(0)/ = 1.37 n e (0) = 1.97x10 20 P ped ~ 175 kPa, approximately what we expect from EPED Te = Ti

6. Ideal MHD stability of high-n ballooning and external kink modes Ballooning unstable on 4 out of 200 surface, all outside pedestal location Weak instabilities, high critical-n number, should use EPED stability analysis for this region External kink modes (using conformal wall, unstable with no conducting wall) Mode numberb/a to stabilize (real distance from plasma surface) n = 10.46 (0.633 m) n = 20.45 (0.619 m) n = 30.425 (0.584 m) Will pursue higher mode numbers, n=4-6, to determine most limiting

7. Further work Examine stability with and without off-axis CD, profile adjustments to accommodate transport or better stability – Check stability convergence Converge free-and fixed boundary equilibria, include different shaping if necessary Develop consistent heating and CD, time-dependent scenario – Converge PPPL and GA results Examine plasmas at higher β N, similar to ARIES-AT, limited by b/a(kink) ~ 0.33, compare with what we are choosing – We have backed away from the highest β N values since experiments don’t appear to access these plasmas…..so what would the right parameters be? – Should the wall be placed at 0.33, with lower β N, providing a % toward the with wall limit? – Based on what experimentalists observe, what would they project for β N, β N /β N wall, q 95, etc. Examine ACT2 candidates