| 17 | 18 | The SMEFT is constructed out of a series of SU(3),,C,, × SU(2),,L,, × U(1),,Y,, invariant (local and analytic) higher dimensional operators L,,6,,, L,,7,,, ... built out of the SM fields. |
| | 19 | |
| | 20 | The SMEFTsim package provides a complete implementation of the dimension-6 Lagrangian adopting the Warsaw basis [https://arxiv.org/abs/1008.4884] and it is designed to enable numerical studies of the LO interference of the SMEFT with the SM, while neglecting NLO corrections. |
| | 21 | |
| | 22 | The SM Lagrangian is extended with the inclusion of the complete set of baryon-number-conserving operators of the Warsaw basis and of the SM loop-induced Higgs couplings to gg, γγ and Zγ. The code assumes unitary gauge: in particular, modifications of the ghost Lagrangian have not been included. |
| | 23 | Importantly, field rotations required to have canonically normalized kinetic terms and parameter redefinitions following from the choice of an input parameters set are automatically applied in the Lagrangian. |
| | 24 | |
| | 25 | The SMEFTsim package provides implementations for 3 different flavor assumptions and 2 input scheme choices, for a total of 6 different models. |
| | 26 | |
| | 27 | The flavor symmetry assumptions adopted are (see [https://arxiv.org/abs/1709.xxxxx] for a detailed description) |
| | 28 | * The flavour general case |
| | 29 | * The U(3)^5 flavor symmetric case, with possible non-SM CP-violating phases |
| | 30 | * A linear Minimal flavor violation (MFV) ansatz, in which non-SM CP-violating effects are neglected, but flavor-violation spurion insertions are allowed in quark currents |
| | 31 | |
| | 32 | For each model it is possible to choose between two input parameters sets for the electroweak sector, namely: |
| | 33 | * α scheme: {α,,em,,, m,,Z,, , G,,f,,} |
| | 34 | * m,,W,, scheme: {m,,W,,, m,,Z,, , G,,f,,} |
| | 35 | |
| | 36 | |
| | 37 | |
| | 38 | each set contains a main file, a number of subroutines and restriction files. |
| | 39 | Pre-exported UFO files to be interfaced with MadGraph5_aMC@NLO can also be downloaded from this page. |
| | 40 | |
| | 41 | |
| 26 | | Each model set constructs three different versions of the SMEFT based on the flavor symmetry assumption adopted: |
| 27 | | * Flavour general SMEFT |
| 28 | | * U(3)^5^ − SMEFT with non-SM complex phases |
| 29 | | * Minimal flavor violation (MFV) SMEFT |
| 30 | | |
| 31 | | In each model two input parameter schemes of choosing external parameters are employed: |
| 32 | | * α scheme: {α,,em,,, m,,Z,, , G,,f,,} |
| 33 | | * m,,W,, scheme: {m,,W,,, m,,Z,, , G,,f,,} |
