  Theoretical calculations Beyond the Standard Model (BSM) constitute a
challenge for high energy physicists, but are necessary when searching for New
Physics. The predictions of a BSM scenario need to be compared with
experimental data and the Standard Model values in order to identify the model
that fits better what we observe in particle colliders. BSM predictions require
very involved and error prone calculations of amplitudes, cross-sections and
Wilson coefficients. Calculations at the one-loop level are often necessary for
these quantities since some phenomenologically important processes may not
occur at tree-level, such as Flavor Changing Neutral Currents (FCNC) in flavor
physics that vanish at the tree-level. One-loop calculations have to be done
analytically which is very time consuming and in practice rarely done for
general BSM models. Here we present MARTY, a public and open-source C++ code.
MARTY is the very first independent program able to calculate automatically
amplitudes, squared amplitudes and Wilson coefficients at the one-loop level
for general BSM models. This type of calculations requires a computer algebra
system and could only be done, up to now, using Mathematica, a commercial and
closed software for symbolic manipulations. MARTY does not rely on Mathematica
since it re-implements its own computer algebra system also in C++, called CSL.
MARTY will considerably ease BSM studies as by automating the analytical
calculations the main task of the user would be the model building part. Once
interfaced with other phenomenological codes in particle physics, MARTY will be
incredibly efficient to make detailed predictions for general BSM models
automatically.
