This tep:tri was prepared ;is .in account of wi-rk sponsored h> :in ^jjeney of the United Slates tJuuTninjni. Neither the Waited States fiuvcrniTvcni nor an> agency thereof, nor any of their DE87 013207 emp.ojccs. makes .in} '*arr:iJiT>, ex pros or implied, or assumes unv legal liability or responsi bility fpf 'he accuracy completeness, nr usefulness of any information, apparatus, product, or protest iJistlyscd. DF represents thill its :JVU U mid not infringe privately owned rights. Refer ence herein in any specific owi martial product, proeey. or service by trade name, trademark, manufacturer, *>r otherwise dixrs not rrcecssjrilv c :ijlituie or imply its endorsement, recom mendation, or favoring by llic United States (I'overnmcnl or any agency thereof. The views and opinions of authors c*prc:;scd herein do nul necessarily stum or reflect those of the United Slates Government or an' agency thereof.

A 19-channel electron cyclotron emission (ECE) grating polychromator~S Th as been added to the existing ECE diagnostics on C-Mod, which include a 9-channel polychromator, heterodyne radiometer and Michelson interferometer.The new instrument can significantly improve the radial resolution of electron power deposition measurements in ICRF experiments on C-Mod. The improved resolution is important for resolving electron power deposition in off-axis mode conversion heating regimes where the mode conversion region can be narrow. The first data from this new instrument were acquired last year during 80 MHz hydrogen minority D-H mode conversion experiments where the IW(H+D) ratio was varied from 0.02 to 0.30 and the toroidal field was varied from 5.1 to 5.7 T. Although complicated by the presence of large sawteeth, some electron power deposition results were obtained from a break-in-slope method. These results, together with results from data acquired during the current C-Mod experimental campaign, will be presented and compared to predicted radial deposition profiles from the TORIC, 2-D full wave RF code, and the METS95, 1-D integral wave RF code.

Data from magnetic pickup loops (Mirnov coils), located on the wail inside the vacuum vessel of TFTR, are used for studying the edge magnetic fluctuations. Experiments, such as impurity injection, gas puffing, and plasma motion, dramatically affect the fluctuations measured by the coils. A quantitative study of the fluctuation levels during these experiments has been made. Results show that there are simple relations between the amount of impurities or gas injected and changes in the fluctuation levels. Spatial locations of the fluctuation modes have also been tentatively identified. Finally, different models were studied in order to explain the behaviour and dependence of the fluctuations on the relevant parameters of the plasma.

In order to study the microscopic physics underlying observed L-mode current scaling, 1-1/2-d BALDUR has been used t,, simulate density and temperature profiles for high and low current, neutral beam heated discharges on TFTR with several semi-empirical, theoretically-based models previously compared for TFTR, including several versions of trapped electron drift wave driven transport. Experiments at TFTR, JET and DIII-D show that Ie scaling of TE does not arise from edge modes as previously thought, and is most likely to arise from nonlocal processes or from the lp-dependence of local plasma core transport. Consistent with this, it is found that strong current scaling does not arise from any of several edge models of resistive ballooning. Simulations with the profile consistent drift wave model and with a new model for toroidal collisionless trapped electron mode core transport in a multimode formalism, lead to strong current scaling of 7"E for the Lmode cases on TFTR. None of the theoretically-based models succeeded in simulating the measured temperature and density profiles for both high and low current experiments. II.

Abstract. Integrated scenario simulations are done for NSTX that address four primary milestones for developing advanced ST configurations: high β and high β N inductive discharges to study all aspects of ST physics in the high beta regime; non-inductively sustained discharges for flattop times greater than the skin time to study the various current drive techniques; non-inductively sustained discharges at high β for flattop times much greater than a skin time which provides the integrated advanced ST target for NSTX; and non-solenoidal startup and plasma current rampup. The simulations done here use the Tokamak Simulation Code (TSC) and are based on a discharge 109070. TRANSP analysis of the discharge provided the thermal diffusivities for electrons and ions, the neutral beam (NB) deposition profile and other characteristics. CURRAY is used to calculate the High Harmonic Fast Wave (HHFW) heating depositions and current drive. GENRAY/CQL3D is used to establish the heating and CD deposition profiles for electron Bernstein waves (EBW). Analysis of the ideal MHD stability is done with JSOLVER, BALMSC, and PEST2. The simulations indicate that the integrated advanced ST plasma is reachable, obtaining stable plasmas with β ≈ 40% at β N 's of 7.7-9, I P = 1.0 MA and B T = 0.35 T. The plasma is 100% non-inductive and has a flattop of 4 skin times. The resulting global energy confinement corresponds to a multiplier of H 98(y,2) = 1.5. The simulations have demonstrated the importance of HHFW heating and CD, EBW off-axis CD, strong plasma shaping, density control, and early heating/H-mode transition for producing and optimizing these plasma configurations