Abstract: The gyrokinetic equations for the electrostatic electron-temperature gradient mo des in toroidal plasmas are solved with particle simulation method. An axisymmet ric geometry with circular flux surfaces is employed. The full kinetics, includi ng finite Larmor radius effects, transit k∥v∥, and toro idal (curvature and magnetic gradient) drift motion, is retained. The basic method of the parti cle simulation is described briefly. The fourth-order adaptive stepsize scheme i s adopted, that saves computer time and is simple. The basic characteristics of the modes are discussed. The scaling of the critical gradient with respect to to roidicity and to the ratio of electron temperature over ion temperature is given . Comparison with experiments are made and the theoretical results are close to the experimental observations.

Keywords: 
• electron-temperature gradient instability /
• particle simulation /
• adaptive stepsize scheme /
• critical gradient