Summations of large logarithms by parton showers

Understand

We propose a method to examine how a parton shower sums large logarithms.

• In this method, one works with an appropriate integral transform of the distribution for the observable of interest.
• Then, one reformulates the parton shower so as to obtain the transformed distribution as an exponential for which one can compute the terms in the perturbative expansion of the exponent.
• We apply this general program to the thrust distribution in electron-positron annihilation, using several shower algorithms.