A flavor-inspired radiative neutrino mass model

Abstract

One of the most important discoveries in particle physics is the observation of nonzero neutrino masses, which dictates that the Standard Model (SM) is incomplete. Moreover, several pieces of evidence of lepton flavor universality violation (LFUV), gathered in the last few years, hint toward physics beyond the SM. TeV-scale scalar leptoquarks are the leading candidates for explaining these flavor anomalies in semileptonic charged and neutral current B-decays, the muon, and the electron magnetic dipole moments that can also participate in neutrino mass generation. In this work, we hypothesize that neutrino masses and LFUV have a common new physics origin and propose a new two-loop neutrino mass model that has the potential to resolve some of these flavor anomalies via leptoquarks and offers rich phenomenology. After deriving the neutrino mass formula for this newly-proposed model, we perform a detailed numerical analysis focusing on neutrino and charged lepton flavor violation phenomenology, where the latter provides stringent constraints on the Yukawa couplings and leptoquark masses. Finally, present and future bounds on the model’s parameter space are scrutinized with exemplified benchmark scenarios.

Scalar leptoquarks at the LHC and flavour anomalies: a comparison of pair-production modes at NLO-QCD

“…Originally proposed in models of Grand Unification [1][2][3][4][5][6][7], they appear in many extensions to the Standard Model, e.g. in superstring models [8], R-parity violating supersymmetric scenarios [9,10], composite models [11][12][13][14][15], neutrino mass models [16][17][18][19][20][21], or as mediators in simplified models of dark matter [22][23][24][25][26][27]. Scalar leptoquarks may also offer an explanation [28][29][30][31][32][33][34][35][36][37][38][39] to the anomalies appearing in B-physics observables [40][41][42][43][44][45][46][47], as well as to the discrepancy between theoretical predictions [48] and e...…”

Framework for neutrino masses and flavor anomalies

“…Besides all these anomalies, SM also fails to incorporate the origin of neutrino masses, firmly confirmed by the oscillation experiments [8,9]. Motivated by this drawbacks of the SM, we propose a new two loop neutrino mass model [10,11] that gives a simultaneous solution to all four of the anomalies mentioned above. The model utilizes two scalar leptoquarks (LQs) {𝑆 1 (3, 1, 1/3) and 𝑅 2 (3, 2, 7/6)} that are directly intertwined with the neutrino mass generation mechanism.…”

“…In addition to the SM particle content, the proposed model [10,11] consists of two scalar LQs (SLQs), 𝑆 1 (3, 1, +1/3), 𝑅 2 (3, 2, 7/6), and another BSM multiplet 𝜉 3 (3, 3, 2/3). We denote their component fields by…”