Simultaneous interpretation of K and B anomalies in terms of chiral-flavorful vectors

Abstract

We address the presently reported significant flavor anomalies in the Kaon and B meson systems such as the CP violating Kaon decay ( / ) and lepton-flavor universality violation in B meson decays (R K ( * ) , R D ( * ) ), by proposing flavorful and chiral vector bosons as the new physics constitution at around TeV scale. The chiral-flavorful vectors (CFVs) are introduced as a 63-plet of the global SU (8) symmetry, identified as the one-family symmetry for left-handed quarks and leptons in the standard model (SM) forming the 8-dimensional vector. Thus the CFVs include massive gluons, vector leptoquarks, and W , Z -type bosons, which are allowed to have flavorful couplings with left-handed quarks and leptons, and flavor-universal couplings to right-handed ones, where the latter arises from mixing with the SM gauge bosons. The flavor texture is assumed to possess a "minimal" structure to be consistent with the current flavor measurements on the K and B systems. Among the presently reported significant flavor anomalies in the Kaon and B meson systems ( / , R K ( * ) , R D ( * ) ), the first two / and R K ( * ) anomalies can simultaneously be interpreted by the presence of CFVs; the R D ( * ) anomaly is predicted not to survive, due to the approximate SU (8) flavor symmetry. Remarkably, we find that as long as both of the / and R K ( * ) anomalies persist beyond the SM, the CFVs predict the enhanced K + → π + νν and K L → π 0 νν decay rates compared to the SM values, which will readily be explored by the NA62 and KOTO experiments, and they will also be explored in new resonance searches at the Large Hadron Collider. Summary and discussion 28A Explicit expressions for CFV couplings to quarks and leptons 34 B Effective four-fermion operators induced from CFV exchanges 37 C Global significance of a benchmark point 39 -1 -

Simultaneous explanation of $K$ and $B$ anomalies in vectorlike compositeness

“…On the other hand in the Kaon sector, the observable, ε ′ /ε, which measures the direct CP violation in K → ππ decays has been focused since sizable discrepancy from the experimental data [(ε ′ /ε) exp = (16.6 ± 2.3) × 10 −4 ] [13,14,15,16] was reported in the standard model (SM) as (ε ′ /ε) SM = (1.06 ± 5.07) × 10 −4 [17] (see also [18]) adopting the first lattice calculation result reported by RBC-UKQCD collaboration [19]. We find various studies on this subject [20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47]. This anomaly would suggest us another hint for surveying possibilities of physics beyond the SM through flavor physics.…”

“…We consider the possible scenario where the B and K anomalies are addressed simultaneously discussed in [38]. Here, the chiral-flavorful vectors (CFVs) are introduced as a 63-plet of the global SU (8) symmetry, identified as the one-family symmetry for left-handed quarks and leptons in the SM forming the 8-dimensional vector, where the 63-plet is decomposed into massive gluonlike, vector-leptoquark-like, W ′ -and Z ′ -like vector particles.…”

Anatomy of $$\varepsilon '/\varepsilon $$ ε ′ / ε beyond the standard model

“…In specific NP models one often finds correlations between BSM contributions to ε /ε and rare kaon decays, in particular with K + → π + νν and K L → π 0 νν. In fact in all papers that addressed the ε /ε anomaly listed in the introduction [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40] such correlations have been investigated. Such correlations will play an important role in distinguishing various models when the theoretical status of ε /ε improves and the branching ratios for rare kaon decays will be well measured.…”

“…These include in particular tree-level Z exchanges with explicit realization in 331 models [22,23] or models with tree-level Z 0 exchanges [24,25] with explicit realization in models with mixing of heavy vector-like fermions with ordinary fermions [26] and the Littlest Higgs model with T-parity [27]. Also simplified Z scenarios [28,29], the MSSM [30][31][32][33][34], the type-III Two-Higgs Doublet model (2HDM) [35,36], a SU (2) L ⊗ SU (2) R ⊗ U (1) B−L model [37,38] and the one based on SU(8) symmetry [39] are of help here. On the other hand, as demonstrated in [40], it is very unlikely that leptoquarks are responsible for the ε /ε anomaly when the constraints from rare semi-leptonic and leptonic K decays are taken into account.…”

Direct CP violation in Cabibbo-favored charmed meson decays and ϵ′/ϵ in SU(2)L × SU(2)R × U(1)B−L model

“…2 For other works on new physics contributions to / , see refs. [31][32][33][34][35][36][37][38][39][40][41][42][43]. the right-right current operators are expressed in terms of the ratio of the Wilson coefficients that is calculable in short-distance QCD, and the diagrammatic amplitudes.…”