The full lepton flavor of the littlest Higgs model with T-parity Águila Giménez, Francisco Del Ametller, Lluis Illana Calero, José Ignacio Santiago Pérez, José Talavera, Pere Vega-Morales, Roberto Beyond Standard Model Effective Field Theories Higgs Physics We thank useful discussions and comments by A. Blondel, A. Falkowski, G. Hernández- Tomé, J. Hubisz, I. Low and J.M. Pérez-Poyatos. This work has been supported in part by the Ministry of Science, Innovation and Universities, under grant numbers FPA2016- 78220-C3-1,2,3-P (fondos FEDER), and by the Junta de Andalucía grant FQM 101 as well as by the Juan de la Cierva program. J.S. and R.V.M. thank the Mainz Institute for Theoretical Physics (MITP) for its hospitality and partial support during the completion of this work. R.V.M. would also like to thank the Fermilab National Accelerator Laboratory and Northwestern University for their hospitality. We re-examine lepton flavor violation (LFV) in the Littlest Higgs model with T-parity (LHT) including the full T-odd (non-singlet) lepton and Goldstone sectors. The heavy leptons induce two independent sources of LFV associated with the couplings necessary to give masses to the T-odd mirror fermions and to their partners in right-handed SO(5) multiplets, respectively. The latter, which have been neglected in the past, can be decoupled from gauge mediated processes but not from Higgs mediated ones and must therefore also be included in a general analysis of LFV in the LHT. We also further extend previous analyses by considering on-shell Z and Higgs LFV decays together with the LFV processes at low momentum transfer. We show that current experimental limits can probe the LHT parameter space up to global symmetry breaking scales f ∼ 10 TeV. For lower f values ≳ 1 TeV, μ − e transitions require the misalignment between the heavy and the Standard Model charged leptons to be ≲ 1%. Future LFV experiments using intense muon beams should be sensitive to misalignments below the per mille level. For τ LFV transitions, which could potentially be observed at Belle II and the LHC as well as future lepton colliders, we find that generically they can not discriminate between the LHT and supersymmetric models though in some regions of parameter space this may be possible. 2020-04-23T11:47:54Z 2020-04-23T11:47:54Z 2019-07-25 info:eu-repo/semantics/article del Aguila, F., Ametller, L., Illana, J.I. et al. The full lepton flavor of the littlest Higgs model with T-parity. J. High Energ. Phys. 2019, 154 (2019). [https://doi.org/10.1007/JHEP07(2019)154] http://hdl.handle.net/10481/61522 10.1007/JHEP07(2019)154 eng http://creativecommons.org/licenses/by/3.0/es/ info:eu-repo/semantics/openAccess Atribución 3.0 España Springer Nature