LA-7082-PR Progress Report UC-20 C.4 Issued: March 1978 I LASL Controlled Thermonuclear Research Program I January – Decem ber 1976 Compiled by Keith S. Thomas I I : 1 ( ) 10s alamos { ). scientific laboratory of the University of California LOS ALAMOS, NEW MEXICO 87545 An AffirmativeAction/EqualOpportunityEmployer UNITED STATES DEPARTMENT OF ENERGY CONTRACT W-740 S-ENG. S6 The four most recent reports in this series, unclassified, are LA-5250-PR, LA-5656-P~ LA-6044-P~ and LA-6582-PR Work supported by US Energy Research and Development Administration, Division of Magnetic Fusion. ?tmtmim W tlnttcdS!.!IC<ofAmcnca.Awdil,hlc!“mm N.tiumdTcchnk.1I“f”rmatttinSCWICC U.S 12qwtmcnta,tCwmmcr.e S285P,,,tK,,ydR,,.d Spnn#ic.ld.VA 11161 Mkrdidlc s 3.011 126.15(17,25 2st.17s 10.7s 376400 I3S1O SOI-525 15.2s (101.(12s 4 ml 1s1.17s 8.00 276-3(IO 11.00 401425 I3.2s 526-55(I 15.s0 1116.0S0 a so 176.20(19.0[1 301.325 !1.75 426.4S0 14(Y2 551.575 16.25 [151.(175 5.25 201.22s 9.2s 326.350 12.(10 4s1.47s 14sl 576600 !6.S0 076.100 6.00 226.2S0 9.s0 3s1-315 [2.s0 476.S0[115,0(1 6CIl+Jp --1 101.125 6.S0 1.Add S2.S0forewh addtttonal10&Pagcmcremcntfrom601paw UP. Thts r.”orL w., p,ep. red .s ●n .cc’,u.1 U( W,,rk so,,nsw.d b. tfw Untt.d S1.tcs G.vrrmnent. Nrtther the Umtcd Stiles nor the Un, ted St.t.s rko.r’m. n, of Fnerw, “or .ny of Ih,u, .rnplcn,qWI ..Y nf them contr.ctws. subco”tr.. tor% or their vmPloYe.s. m.km .m w.m.nt., express or mmh.d. or .-..,.s .nY I.M[ lIabti:IY or resPon$1611ttYf-r the . ...Y. .,,rnplelcncs. m ..ef.lness of .ny lnf,, rm41i,, n, .pp.r.l us. pr,,duct, w process dwh,s++. or r.w.w.t. th.t ,1s.s. -,s,,1,! not mfcmm iw%..tc!y own-dnnhts. ABSTRACT This report presents the status of the Controlled Thermonuclear Research Program at the Los Alamos Scientific Laboratory for calendar year 1976. CONTENTS I. INTRODUCTION .......................................................................... 1 II. SCYLLAC FEEDBACK SECTOR EXPERIMENTS ................................................... 3 A. Introduction and Summary .......................................................... 3 B. Review of Scyllac Theory .......................................................... 5 c. Experimental Arrangement .......................................................... 7 D. Results with Feedback Stabilization in a Uniform Toroidal Discharge Tube .......... 11 E. Results with a Helical Discharge Tube ............................................. 15 F. Excluded Flux Measurements ........................................................ 19 G. Propagation ofm=l Waves ........................................................ 20 H. Diffusion ......................................................................... 23 I. Scyllac Magnetohydrodynamics ...................................................... 27 J. Scyllac Feedback System Development ............................................... 32 K. Preparations for ?.=1,2 Equilibrium Experiments .................................. 34 L. Similarity Between Wall Stabilization and E = 2 Feedback .......................... 38 References ............................................................................ 39 III. STAGED THETA-PINCH PROGRAM ............................................................ 41 A. Introduction ........................,............................................. 41 B. Staged Theta Pinch ............,..,................................................ 41 c. Resonant Heating Experiment ....................................................... 46 D. Summary ....................,...................................................... 49 References ............................................................................ 49 Iv. TOROIDAL REVERSED-FIELD PINCH ......................................................... 50 A. Summary ...........,............................................................... 50 B. Comparison of ZT-1 and ZT-S Stability Results ..................................... 50 c. Field Diffusion and Ideal MHD Stability ........................................... 53 D. Resistive MHD Stability ........................................................... 57 E. Temperature and Density Measurements on ZT-S ...................................... 58 F. Plasma Impurities ................................................................. 60 —. L*-= . —- -- G. Energy Balance Measurements on ZT-S ............................................... 64 p-” H. ZT-40 Toroidal, Reversed-Field Z-Pinch ............................................ 64 i- References ............................................................................ 66 SCYLLtiIV-P -iINti’THE+A-PINCtlEXPERIMENTS ............................................ 67 F=,“ A. Introduction ...................................................................... 67 i=- t B. Experimental Arrangement .......................................................... 67 k c. Experimental Results Without End Plugs .,.......................................... 69 ~~ ~ D. Plasma End Loss St:d;e_s............................................................ 76 — l+—-- - ... - —. - -+ K’ E. Initial Experimental Results with Solid End Plugs ................................. P3 References ................ ,. ., . 86 iii — VI. GUN INJECTION EXPERIMENT ............................................................. 88 A. Introduction ..................................................................... 68 B. Experimental Results ............................................................. B9 c. Summary and Plans for Further Investigation ...................................... 92 References ........................................................................... 93 VII. SCYLI.AI-C, LASER-PLASMA INTERACTION STUDIES ......................................... 94 A. Introduction ..................................................................... 94 B. Interferometry ................................................................... 94 c. Plasma Spectroscopy .............................................................. 96 D. Calorimetry ...................................................................... 97 E. Backacatter Spectroscopy ......................................................... 9B F. Summary .......................................................................... 99 References ........................................................................... 99 VIII. FIELD REVERSAL THETA PINCH ........................................................... 100 A. Introduction ..................................................................... 100 B. Description ...................................................................... 101 c. Engineering ...................................................................... 102 D. Diagnostics ...................................................................... 103 E. Experimental Program and Plasma Results .......................................... 104 F. Conclusion ....................................................................... 104 References ........................................................................... 104 IX. IMPLOSION HEATING EXPERTMSNT (IHX) ................................................... 106 A. Introduction and Summary ......................................................... 106 B. Experimental Results ............................................................. 106 c. Diagnostic Improvements ......................................................,... 107 References ........................................................................... 109 x. EXPERIMENTAL PLASMA PHYSICS .......................................................... 110 A. Summary ...............................................................,.......... 110 B. Electromagnetic Wave Absorption, Plasma Heating and Energy Transport in the Q-Machine .................................................. 110 c. Progress on an Experiment for Studying Nonlinear Interactions Between Plasma and Travelling Electromagnetic Waves ................................. 124 D. Q-Machine Hot Plate Development .................................................. 125 References ...........................................................-...s........... 125 XI. PLASMA DIAGNOSTICS ................................................................... 127 A. Introduction ..................................................................... 127 B. Spatially Resolved Thomson Scattering ............................................ 127 c. Heterodyne T.nterferometry........................................................ 133 D. On-Line Beta Measurement for Scylla IV-P ......................................... 137 E. Miscellaneous .................................................................... 139 References ............................................................,...,.......... 140 iv — XII. HIGH-BETA TOKAMAX ................................................................... 141 A. Introduction .................................................................... 141 B. High-Beta Tokamak Physics ....................................................... 141 c. Construction of the Proposed Machine ............................................ 141 D. Comparison with Other Experiments ............................................... 142 E. Problems at Long Confinement .................................................... 143 XIII. THEORY .............................................................................. 144 A. Introduction ...................................................................