Confronting spin-3/2 and other new fermions with the muon g-2 measurement Criado, Juan Carlos Djouadi, Abdelhak This work was supported by the Estonian Research Council grants MOBTTP135 , PRG803 , MOBTT5 , MOBJD323 and MOBTT86 , and by the EU through the European Regional Development Fund CoE program TK133 “The Dark Side of the Universe.” J.C.C. is supported by the STFC under grant ST/P001246/1 , and A.D. is also supported by the Junta de Andalucía through the Talentia Senior program as well as by A-FQM-211-UGR18 , P18-FR-4314 with ERDF. The new measurement of the muon's anomalous magnetic moment released by the Muon g-2 experiment at Fermilab sets strong constraints on the properties of many new particles. Using an effective field theory approach to the interactions of higher-spin fields, we evaluate the contribution of an electrically neutral and colour singlet spin-3/2 fermion to (g−2)μ and derive the corresponding constraints on its mass and couplings. These constraints are then compared with the ones on spin-1/2 fermions, such as the vector-like leptons that are predicted by various extensions of the Standard Model, the excited leptons which appear in composite models, as well as the charginos and neutralinos of supersymmetric theories. Unlike these new spin-1/2 fermions, the spin-3/2 particles generate only small contributions to the muon anomalous magnetic moment unless the effective new physics scale is very close to the electroweak scale. 2021-11-08T12:26:09Z 2021-11-08T12:26:09Z 2021-09-10 info:eu-repo/semantics/article J.C. Criado, A. Djouadi, N. Koivunen et al. Confronting spin-3/2 and other new fermions with the muon g-2 measurement. Physics Letters B 820 (2021) 136491. [https://doi.org/10.1016/j.physletb.2021.136491] http://hdl.handle.net/10481/71372 10.1016/j.physletb.2021.136491 eng http://creativecommons.org/licenses/by/3.0/es/ info:eu-repo/semantics/openAccess Atribución 3.0 España Elsevier