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A collection of limits on heavy neutral leptons, including their nuSMEFT interactions

Project description

Heavy Neutrino Limits

This package and repo tracks the constraints on the coupling and masses of heavy neutral leptons (HNL). To access it, simply clone this repository.

To use the underlying functions to create your own plots and latex files, you can install HNLimits as you would a standard PyPI package, python -m pip install HNLimits. You can then import it in your Python script import HNLimits.

All limits are kept track in this Google Spreadsheets.

  • We consider single flavor dominance scenarios, where the HNL mixes predominantly with either the electron, muon, or tau flavor.

  • Following the accompanying paper, we provide limits on the Wilson coefficients of dimesnion-six ν SMEFT operators as a function of the HNL mass MN.

  • The code keeps track of limits in the region 1 MeV <MN<100 GeV.

Additions, comments, or suggestions should be directed to:


Citation info:

arxiv.org/abs/2304.06772

@article{Fernandez-Martinez:2023phj,
    author = "Fern\'andez-Mart\'\i{}nez, Enrique and Gonz\'alez-L\'opez, Manuel and Hern\'andez-Garc\'\i{}a, Josu and Hostert, Matheus and L\'opez-Pav\'on, Jacobo",
    title = "{Effective portals to heavy neutral leptons}",
    eprint = "2304.06772",
    archivePrefix = "arXiv",
    primaryClass = "hep-ph",
    reportNumber = "FTUV-23-0303.1224, IFIC/23-09",
    doi = "10.1007/JHEP09(2023)001",
    journal = "JHEP",
    volume = "09",
    pages = "001",
    year = "2023"
}

Limits on the mixing

Current compilation of bounds on the mixing of HNLs with a single flavor:

Electron mixing e flavor

Muon mixing mu flavor

Tau mixing tau flavor


Limits on the dimension-six νSMEFT operators

Type Name Operator Notebook Figure
Mixing Omixing LH~N 0_limits_mixing.ipynb electron
muon
tau
Higgs-dressed Mixing OLNHα LH~N(HH) 1_NSMEFT_LHN.ipynb electron
muon
tau
Bosonic Currents OHN NγμN(HiDμH) 2_NSMEFT_bosonic_NC.ipynb Bosonic NC
OHNα Nγμα(H~iDμH) 3_NSMEFT_bosonic_CC.ipynb Bosonic CC
Moments ONBα (LασμνN)H~Bμν 4_NSMEFT_moment_NB.ipynb Moment hypercharge
ONWα (LασμνN)τaH~Waμν 5_NSMEFT_moment_NW.ipynb Moment W
4-fermion NC Off (fγμf)(NγμN) 6_NSMEFT_4fermion_NC_ff_LN.ipynb 4-fermion ee
4-fermion uu
4-fermion dd
OLNα (LαγμLα)(NγμN) 6_NSMEFT_4fermion_NC_ff_LN.ipynb 4-fermion LN
OQN (QiγμQi)(NγμN) 7_NSMEFT_4fermion_NC_QN.ipynb 4-fermion QN
4-fermion NC & CC OLNLαβ (LαN)ϵ(Lαβ) 8_NSMEFT_4fermion_LNLell.ipynb 4-fermion LNLell NC
4-fermion LNLell CC
4-fermion CC OduNα ZijduN(diγμuj)(Nγμα) 9_NSMEFT_4fermion_CC_duNell.ipynb 4-fermion duNell: electron
4-fermion duNell: muon
4-fermion duNell: tau
OLNQdα ZijLNQd(LαN)ϵ(Qidj) 10_NSMEFT_4fermion_CC_LNQd.ipynb 4-fermion LNQd: electron
4-fermion LNQd: muon
4-fermion LNQd: tau
OQuNLα ZijQuNL(Qiuj)(NLα) 11_NSMEFT_4fermion_CC_QuNL.ipynb 4-fermion QuNL: electron
4-fermion QuNL: muon
4-fermion QuNL: tau

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