1. Code Name: NOVA-W

2. Category: VIIa. Linear Stability: 2D Ideal

3. Responsible Physicist: C. Z. Cheng

4. Others involved in code development: D. J. Ward, S. Jardin

5. One line description: Feedback stability code for ideal and resistive modes in tokamaks.

6. Computer systems which code runs on: Cray

7. Typical running time: 20 minutes/Cray time

8. Approximate number of code lines: 10,000 lines.

9. Does this code read data files from another code? yes, It reads equilibrium data from equilibrium code.

11. 1-2 paragraph description of code: The NOVA-W computes real frequency and growth rate of MHD modes in deformable tokamak plasmas due to the effects of resistive passive conductors and active feedback circuits as well as toroidal plasma rotation. The NOVA-W code is a modification of the nonvariational MHD stability code NOVA with vacuum calculations reformulated in terms of the perturbed poloidal flux to allow the inclusion of perturbed toroidal currents outside the plasma.

12. Similar codes to this code, and distinguishing differences: No other similar eigenvalue stability codes.

13. Journal References describing code (up to 3): D. J. Ward, S. C. Jardin, and C. Z. Cheng, J. Comput. Phys. 104, 221 (1993)

14. New code capabilities planned for next 1-2 years: To include the differential plasma rotation effects.

15. Code users: D. J. Ward, S. C. Jardin, C. Z. Cheng.

16. Present and recent applications of code: Calculation of MHD stability of tokamak plasmas with active and passive feedback.

17. Status of code input/output documentation. Check one: (X) does not exist ( ) incomplete ( ) exists

18. Year Code was first used and present frequency of use: 1992. The code is presently used mainly by D.J. Ward for studying rigid toroidal rotation effects on MHD modes.

19. Estimate of Man-Years invested in developing code: 3 man years.

20. Catagories of usage of Code (Check all that apply): (X) application code to do analysis and prediction of experiments (X) numerical testbed of theoretical ideas ( ) physics module to be used in integrated moddelling ( ) code for machine design

21. Language code is writen in: Fortran

22. Results of intercomparisons with other codes and results of validation against experiments. The code results has been checked against time dependent MHD codes.