The fastjet package provides a fast implementation of several longitudinally invariant sequential recombination jet algorithms, in particular the longitudinally invariant kt jet algorithm, the inclusive longitudinally invariant version of the cambridge/aachen jet-algorithm, and the inclusive anti-kt algorithm.

fastjet also provides a uniform interface to external jet finders via a plugin mechanism, and tools for calculating jet areas and performing background (pileup/ue) subtraction.

this package provides various tools related to jet areas and subtraction. they can be used with any infrared safe jet algorithm, both native and plugin.