Finite-<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi>β</mml:mi></mml:mrow><mml:mrow><mml:mi>e</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math>Universal-Mode Turbulence and Alcator Scaling

A self-consistent theory of finite-${\ensuremath{\beta}}_{e}$ universal-mode turbulence is developed. Saturation results from resonance broadening of the electron response due to magnetic shear. Electron diffusion, for ${\ensuremath{\beta}}_{e}&gt;\frac{{m}_{e}}{{m}_{i}}$, is due to the magnetic part of the fluctuations. The diffusion coefficient, $D=0.1 {[\frac{{T}_{e}}{({T}_{i}+{T}_{e})}]}^{4}(\frac{{m}_{e}}{{m}_{i}{\ensuremath{\beta}}_{e}}){(\frac{{L}_{s}}{{L}_{n}})}^{2}\frac{{v}_{i}{{\ensuremath{\rho}}_{i}}^{2}}{{L}_{n}}$, scales inversely with density, is independent of magnetic field, and is in excellent quantitative agreement with observations on the Alcator tokamak.