PYTHIA Status Report

Recent improvements in the Pythia event generator are summarized: new hard subprocesses, γ ∗ γ ∗ physics, QCD final-state showers, and more. Since 1997, the Jetset 7.4, Pythia 5.7 [1] and SPythia [2] programs have been joined in the new Pythia 6.1 event generator [3]. The current version is 6.156, consisting of some 53,000 lines of Fortran 77 code. The code, update notes, the older long manual and sample main programs may be found at the webpage http://www.thep.lu.se/ ∼ torbjorn/Pythia.html while a new complete long manual is in preparation. A general-purpose high-energy physics event generator, such as Pythia , need to contain a simulation of several physics aspects.