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Operator Bases in Effective Field Theories with Sterile Neutrinos: $d leq 9$

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 نشر من قبل Jiang-Hao Yu
 تاريخ النشر 2021
  مجال البحث
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We obtain the complete and independent bases of effective operators at mass dimension 5, 6, 7, 8, 9 in both standard model effective field theory with light sterile right-handed neutrinos ($ u$SMEFT) and low energy effective field theory with light sterile neutrinos ($ u$LEFT). These theories provide systematical parametrizations on all possible Lorentz-invariant physical effects involving in the Majorana/Dirac neutrinos, with/without the lepton number violations. In the $ u$SMEFT, we find that there are 2 (18), 29 (1614), 80 (4206), 323 (20400), 1358 (243944) independent operators with sterile neutrinos included at the dimension 5, 6, 7, 8, 9 for one (three) generation of fermions, while 24, 5223, 3966, 25425, 789426 independent operators in the $ u$LEFT.



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