Test of Lepton-Flavor Universality in B → K * ℓ + ℓ − Decays at Belle

Self Cite

An angular analysis of the rare decay $$ {B}_s^0 $$ B s 0 → ϕμ+μ− is presented, using proton-proton collision data collected by the LHCb experiment at centre-of-mass energies of 7, 8 and 13 TeV, corresponding to an integrated luminosity of 8.4 fb−1. The observables describing the angular distributions of the decay $$ {B}_s^0 $$ B s 0 → ϕμ+μ− are determined in regions of q2, the square of the dimuon invariant mass. The results are consistent with Standard Model predictions.

Section: Introductionmentioning

confidence: 99%

Angular analysis of the rare decay $$ {B}_s^0 $$ → ϕμ+μ−

Aaij

Abdelmotteleb

Beteta

et al. 2021

Self Cite

“…These couplings are nonzero in our flavor structures 2 and 4 in table 1, where we assume 9 See also ref. [156] for a measurement of RK * at Belle with far larger error bars.…”

Section: Jhep10(2021)182mentioning

confidence: 98%

Searching for leptoquarks at future muon colliders

Asadi

Capdevilla

Cesarotti

et al. 2021

A high energy muon collider can provide new and complementary discovery potential to the LHC or future hadron colliders. Leptoquarks are a motivated class of exotic new physics models, with distinct production channels at hadron and lepton machines. We study a vector leptoquark model at a muon collider with $$ \sqrt{s} $$ s = 3, 14 TeV within a set of both UV and phenomenologically motivated flavor scenarios. We compute which production mechanism has the greatest reach for various values of the leptoquark mass and the coupling between leptoquark and Standard Model fermions. We find that we can probe leptoquark masses up to an order of magnitude beyond $$ \sqrt{s} $$ s with perturbative couplings. Additionally, we can also probe regions of parameter space unavailable to flavor experiments. In particular, all of the parameter space of interest to explain recent low-energy anomalies in B meson decays would be covered even by a $$ \sqrt{s} $$ s = 3 TeV collider.

“…• From the global fits [35][36][37][38][39][40][41][42][43][44][45][46] to various b → sl + l − data [47][48][49][50][51][52][53][54][55][56][57][58][59][60][61], the discrepancy is more than 5σ from the SM predictions. The new result [62] further strengthens the lepton flavor universality violation [63,64].…”

Section: Jhep09(2021)043mentioning

confidence: 99%

One colorful resolution to the neutrino mass generation, three lepton flavor universality anomalies, and the Cabibbo angle anomaly

Chang

2021

We propose a simple model to simultaneously explain four observed flavor anomalies while generating the neutrino mass at the one-loop level. Specifically, we address the measured anomalous magnetic dipole moments of the muon, ∆aμ, and electron, ∆ae, the observed anomaly of b → sl+l− in the B-meson decays, and the Cabibbo-angle anomaly. The model consists of four colorful new degrees of freedom: three scalar leptoquarks with the Standard Model quantum numbers (3, 3, −1/3), (3, 2, 1/6), and (3, 1, 2/3), and one pair of down-quark-like vector fermion in (3, 1, −1/3). The baryon number is assumed to be conserved for simplicity.Phenomenologically viable solutions with the minimal number of real parameters can be found to accommodate all the above-mentioned anomalies and produce the approximate, close to 1σ, neutrino oscillation pattern at the same time. From general consideration, the model robustly predicts: (1) neutrino mass is of the normal hierarchy type, and (2) $$ {\mathcal{M}}_{ee}^{\nu } $$ M ee ν ≲ 3 × 10−4 MeV.The possible UV origin to explain the flavor pattern of the found viable parameter space is briefly discussed. The parameter space can be well reproduced within a simple split fermion toy model.