Paper detail

GR@PPA Event Generator

The history and the present status of the GR@PPA event generator are briefly reviewed. The development of GR@PPA started in 2000 in order to provide a framework of NLO event generators for hadron collision interactions. After the first release of the package (GR@PPA\_4b) in 2002, which supported four bottom quark production processes, many multi-particle production processes have been added to the package: GR@PPA\_ALL in 2004 and GR@PPA 2.7 in 2006. Now we are going to release a new package (GR@PPA 2.8), which supports single and double weak-boson production processes with an initial-state jet matching. Though the matrix elements presently included are still at the tree level, this new release is an important step towards constructing consistent NLO event generators.