The Jet Multiplicity as a Function of Thrust
  We calculate the average multiplicity of jets in e+e- annihilation as a function of both the jet resolution parameter, y_cut, and the thrust T. Our result resums to all orders the leading and next-to-leading logarithms in y_cut and 1-T, and is exact up to second order in alpha_s. This allows a comparison between the number of jets found using jet algorithms and the ability to distinguish different jet topologies via thrust. 
D. J. Miller (RAL) and Michael H. Seymour (RAL)