A low-energy perspective on the minimal left-right symmetric model

Jul 22, 2021
69 pages
Published in:
  • JHEP 11 (2021) 127
  • Published: Nov 17, 2021
e-Print:
Report number:
  • LA-UR-21-26789

Citations per year

202120222023202459186
Abstract: (Springer)
We perform a global analysis of the low-energy phenomenology of the minimal left-right symmetric model (mLRSM) with parity symmetry. We match the mLRSM to the Standard Model Effective Field Theory Lagrangian at the left-right-symmetry breaking scale and perform a comprehensive fit to low-energy data including mesonic, neutron, and nuclear β-decay processes, ∆F = 1 and ∆F = 2 CP-even and -odd processes in the bottom and strange sectors, and electric dipole moments (EDMs) of nucleons, nuclei, and atoms. We fit the Cabibbo-Kobayashi-Maskawa and mLRSM parameters simultaneously and determine a lower bound on the mass of the right-handed WR_{R} boson. In models where a Peccei-Quinn mechanism provides a solution to the strong CP problem, we obtain MWR {M}_{W_R} ≳ 5.5 TeV at 95% C.L. which can be significantly improved with next-generation EDM experiments. In the P-symmetric mLRSM without a Peccei-Quinn mechanism we obtain a more stringent constraint MWR {M}_{W_R} ≳ 17 TeV at 95% C.L., which is difficult to improve with low-energy measurements alone. In all cases, the additional scalar fields of the mLRSM are required to be a few times heavier than the right-handed gauge bosons. We consider a recent discrepancy in tests of first-row unitarity of the CKM matrix. We find that, while TeV-scale WR_{R} bosons can alleviate some of the tension found in the Vud,us_{ud,us} determinations, a solution to the discrepancy is disfavored when taking into account other low-energy observables within the mLRSM.
Note:
  • 42 pages plus appendices. Published version
  • Beyond Standard Model
  • CP violation
  • Effective Field Theories
  • new physics
  • model: left-right
  • model: minimal
  • symmetry: left-right
  • effective Lagrangian
  • effective field theory
  • flavor: violation