اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدUnified Framework for $B$-Anomalies, Muon $g-2$, and Neutrino Masses
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We present a model of radiative neutrino masses which also resolves anomalies reported in $B$-meson decays, $R_{D^{(star)}}$ and $R_{K^{(star)}}$, as well as in muon $g-2$ measurement, $Delta a_mu$. Neutrino masses arise in the model through loop diagrams involving TeV-scale leptoquark (LQ) scalars $R_2$ and $S_3$. Fits to neutrino oscillation parameters are obtained satisfying all flavor constraints which also explain the anomalies in $R_{D^{(star)}}$, $R_{K^{(star)}}$ and $Delta a_mu$ within $1, sigma$. An isospin-3/2 Higgs quadruplet plays a crucial role in generating neutrino masses; we point out that the doubly-charged scalar contained therein can be produced in the decays of the $S_3$ LQ, which enhances its reach to 1.1 (6.2) TeV at $sqrt s=14$ TeV high-luminosity LHC ($sqrt s=100$ TeV FCC-hh). We also present flavor-dependent upper limits on the Yukawa couplings of the LQs to the first two family fermions, arising from non-resonant dilepton ($pp rightarrow ell^+ ell^-$) processes mediated by $t$-channel LQ exchange, which for 1 TeV LQ mass, are found to be in the range $(0.15 - 0.36)$. These limits preclude any explanation of $R_{D^{(star)}}$ through LQ-mediated $B$-meson decays involving $ u_e$ or $ u_mu$ in the final state. We also find that the same Yukawa couplings responsible for the chirally-enhanced contribution to $Delta a_mu$ give rise to new contributions to the SM Higgs decays to muon and tau pairs, with the modifications to the corresponding branching ratios being at (2-6)% level, which could be tested at future hadron colliders, such as HL-LHC and FCC-hh.
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