JFIT: a framework to obtain combined experimental results through joint fits

Abstract

A master-worker architecture is presented for obtaining combined experimental results through joint fits of datasets from several experiments. The design of the architecture allows such joint fits to be performed keeping the data separated, in its original format, and using independent fitting environments. This allows the benefits of joint fits, such as ensuring that correlations are correctly taken into account and better determination of nuisance parameters, to be harnessed without the need to reformat data samples or to rewrite existing fitting code. The Jfit framework is a C++ implementation of this idea in the Laura++ package, using dedicated classes of the ROOT package. We present the Jfit framework, give instructions for its use, and demonstrate its functionalities with concrete examples.