Abstract
Searches for new physics (NP) at particle colliders typically involve multivariate analysis of kinematic distributions of final state particles produced in a decay of a hypothetical NP resonance. Since the pair-production cross-sections mediated by such resonances are strongly suppressed by the NP scale, this analysis becomes less relevant for NP searches for masses of the BSM resonance above 1 TeV. On the other hand, t-channel processes are less sensitive to the mass of the virtual mediator and therefore larger phase-space can be potentially probed as well as the couplings between the NP particles and the Standard Model fields. The fact that transitions between different generations of quarks and leptons may exist, the potential of the search presented in this article can be used, as a reference guide, to enlarge significantly the scope of searches performed at the LHC to flavour off-diagonal channels, in a theoretically consistent approach. In this work, we study non-resonant production of scalar leptoquarks which have been proposed in the literature to provide a potential avenue for radiative generation of neutrino masses, accommodating as well the existing flavour physics data. Final states involving just two muons at the LHC (μ+μ−), are used as a well-motivated case study.
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Acknowledgments
The authors would like to thank Werner Porod for insightful discussions that contributed to the final shape of this manuscript. The authors would also like to thank Tanumoy Mandal for pointing out the impact of the interference between the SM and LQ diagrams and Alexander Belyaev for discussions on the impact of interference effects and systematic errors on the exclusion bounds. J.G. and A.P.M. are supported by the Center for Research and Development in Mathematics and Applications (CIDMA) through the Portuguese Foundation for Science and Technology (FCT - Fundação para a Ciência e a Tecnologia), references UIDB/04106/2020 and UIDP/04106/2020. A.P.M. is supported by the project PTDC/FIS-PAR/31000/2017. A.P.M. and J.G. are also supported by the projects CERN/FIS-PAR/0019/2021, CERN/FIS-PAR/0021/2021, CERN/FISPAR/0019/2021 and CERN/FIS-PAR/0025/2021 J.G. is also directly funded by FCT through the doctoral program grant with the reference 2021.04527.BD. A.P.M. is also supported by national funds (OE), through FCT, I.P., in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19. R.P. and J.G. are supported in part by the Swedish Research Council grant, contract number 2016-05996, as well as by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 668679). A.O. acknowledges support from national funds from FCT, under the project CERN/FIS-PAR/0037/2021.
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Gonçalves, J., Morais, A.P., Onofre, A. et al. Exploring mixed lepton-quark interactions in non-resonant leptoquark production at the LHC. J. High Energ. Phys. 2023, 147 (2023). https://doi.org/10.1007/JHEP11(2023)147
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DOI: https://doi.org/10.1007/JHEP11(2023)147