Comparative study of the forward and backward methods for calculating jet properties in pp collisions at √s=7 TeV * * Supported by the National Natural Science Foundation of China (11477130, 11775094), the 111 project of the foreign expert bureau of China. YLY, AL and YY acknowledge the financial support from Suranaree University of Technology and the Office of the Higher

Abstract

We propose a forward method based on PYTHIA6.4 to study the jet properties in ultra-relativistic pp collisions. In the forward method, the partonic initial states are first generated with PYTHIA6.4 and then hadronized in the Lund string fragmentation model, and finally the hadronic jets are constructed from the created hadrons. Jet properties calculated with the forward method for pp collisions at =7 TeV are comparable to those calculated with the usual anti- algorithm (backward method) in PYTHIA6.4. The comparison between the backward and forward methods may contribute to the understanding of the partonic origin of jets in the backward method.