McMule

Yannick Ulrich _images/orcid.png[1], Pulak Banerjee _images/orcid.png[2], Antonio Coutinho _images/orcid.png[3], Tim Engel _images/orcid.png[4], Andrea Gurgone _images/orcid.png[5] [6], Franziska Hagelstein _images/orcid.png[7] [8], Sophie Kollatzsch _images/orcid.png[8] [9], Luca Naterop _images/orcid.png[8] [9], Marco Rocco _images/orcid.png[8], Nicolas Schalch _images/orcid.png[1], Vladyslava Sharkovska _images/orcid.png[8] [9], Adrian Signer _images/orcid.png[8] [9], Zach McBrearty _images/orcid.png[10]

Contents:

(Monte carlo for Muons and other leptons) is a generic framework for higher-order QED calculations of scattering and decay processes involving leptons. It is written in Fortran 95 with two types of users in mind. First, several processes are implemented, some at NLO, some at NNLO. For these processes, the user can define an arbitrary (infrared safe), fully differential observable and compute cross sections and distributions. McMule’s processes, present and, future, are listed in Table 8 together with the relevant experiments for which the cuts are implemented. Second, the program is set up s.t. additional processes can be implemented by supplying the relevant matrix elements.

Table 8 Processes implemented in McMule

process

order

experiments

comments

\(\mu\to\nu\bar\nu e\)

NNLO

MEG I&II

polarised, massified & exact

\(\mu\to\nu\bar\nu e\gamma\)

NLO

MEG I

polarised

\(\mu\to\nu\bar\nu eee\)

NLO

Mu3e

polarised

\(\mu\to\nu\bar\nu e\gamma\gamma\)

LO

MEG

polarised

\(\tau\to\nu\bar\nu e\gamma\)

NLO

BaBar

cuts in lab frame

\(\tau\to\nu\bar\nu l\ell\ell\)

NLO

Belle II

NLO

MUonE

NNLO

purely electronic corrections

mixed (massified)

\(\ell p\to\ell p\)

NNLO

P2, MUSE, Prad

only leptonic corrections

\(e^-e^-\to e^-e^-\)

NNLO

Prad

complete

\(e^+e^-\to e^+e^-\)

NNLO

no \(n_f\)

\(e^+e^-\to \gamma\gamma\)

NNLO

PADME

\(e^+e^-\to \mu^+\mu^-\)

NNLO

Belle

massified

The public version of the code can be found at

To obtain a copy of the code, git is recommended

$ git clone --recursive https://gitlab.com/mule-tools/mcmule

Alternatively, we provide a Docker container for easy deployment and legacy results (cf. Section Basics of containerisation). In multi-user environments, udocker can be used instead. In either case, a pre-compiled copy of the code can be obtained by calling

$ docker pull yulrich/mcmule  # requires Docker to be installed
$ udocker pull yulrich/mcmule # requires udocker to be installed

We provide instructions on how is used in Section Getting started.

Indices and tables