STATIONARY TURBULENT SPECTRA OF TOROIDAL ETA(I) MODE

Toroidal ion temperature gradient (ITG) driven drift mode turbulence h as been analyzed analyti- cally and numerically. By using weak nonline arity arguments and random phase approximation, dynamic and wave kinet ic equations are derived. Three different nonlinearities, namely ExB, convective, and diamagnetic nonlinearities, play important roles in th e turbulent spectral transfer. The power spectra of tile weak ITG-mode turbulence are obtained analytically for \k\much greater than 1 and \ k\<1 ranges in the wave number space. Foward energy cascading due to c onvective and diamagnetic nonlinearities will balance the inverse ener gy cascading due to ExB nonlinearity at \k\approximate to 1/p(s) (k is the wave number, p(s)=c(s)/omega(ci), where c(s) is the sound velocit y and omega(ci) is the ion cyclotron frequency and results in energy c ondensation at \k\approximate to 1/p(s). (C) 1996 American Institute o f Physics.