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Related papers: Invoking Chiral Vector Leptoquark to explain LFU v…

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We study limits from dilepton searches on leptoquark completions to the Standard Model in the parameter space motivated by anomalies in the $b \rightarrow s$ sector. After a full Run-2 analysis by LHCb, the disparity in lepton flavour…

High Energy Physics - Phenomenology · Physics 2023-01-05 Nishita Desai , Amartya Sengupta

In light of recent measurements suggesting potential lepton flavor universality violations in semileptonic decays at collider experiments, this article provides a concise study of tree- and loop-level $B$-hadron semileptonic decays, $b \to…

High Energy Physics - Phenomenology · Physics 2025-02-05 Sonali Patnaik , Lopamudra Nayak , Rajeev Singh

We investigate the consequence of vector leptoquarks on the rare semileptonic lepton flavour violating decays of $B$ meson which are more promising and effective channels to probe the new physics signal. We constrain the resulting new…

High Energy Physics - Phenomenology · Physics 2017-02-22 Murugeswaran Duraisamy , Suchismita Sahoo , Rukmani Mohanta

We show that by adding a single new scalar particle to the Standard Model, a TeV-scale leptoquark with the quantum numbers of a right-handed down quark, one can explain in a natural way three of the most striking anomalies of particle…

High Energy Physics - Phenomenology · Physics 2016-04-13 Martin Bauer , Matthias Neubert

Recent hints for lepton-universality violation in $b\to c\ell\nu$ and $b\to s\ell\ell$ transitions could imply the existence of lepton-flavour violating $b$ decays. The LHCb experiment is well suited for the search for these decays due to…

High Energy Physics - Experiment · Physics 2018-09-19 Luca Pescatore

In recent years, exciting (indirect) hints for physics beyond the Standard Model (SM) have been accumulated. In particular, semi-leptonic $B$ decays show deviations from the SM predictions, which, due to the ratios $R(K^{(*)})$ and…

High Energy Physics - Phenomenology · Physics 2022-04-27 Andreas Crivellin , Joaquim Matias

We analyze $K\to \pi \nu\bar \nu$ rates in a model with a TeV-scale leptoquark addressing $B$-meson anomalies, based on the flavor non-universal 4321 gauge group featuring third-generation quark-lepton unification. We show that, together…

High Energy Physics - Phenomenology · Physics 2022-10-27 Òscar L. Crosas , Gino Isidori , Javier M. Lizana , Nudzeim Selimovic , Ben A. Stefanek

The collection of a few anomalies in semileptonic $B$-decays, especially in $b\rightarrow c \tau \bar{\nu}$, invites to speculate about the emergence of some striking new phenomena, perhaps interpretable in terms of a weakly broken $U(2)^n$…

High Energy Physics - Phenomenology · Physics 2017-01-06 Riccardo Barbieri , Christopher W. Murphy , Fabrizio Senia

Leptoquarks have been suggested to solve a variety of discrepancies between the expected and observed phenomenon. In this paper, we show that the scalar doublet Leptoquark with Hypercharge 7/6 can simultaneously explain the recent…

High Energy Physics - Phenomenology · Physics 2018-05-23 Bhavesh Chauhan , Bharti Kindra , Ashish Narang

The LHCb measurements of the $\mu / e$ ratio in $B \to K \ell \ell$ decays $(R_{K^{}})$ indicate a deficit with respect to the Standard Model prediction, supporting earlier hints of lepton universality violation observed in the…

High Energy Physics - Phenomenology · Physics 2022-01-12 Guo-yuan Huang , Sudip Jana , Farinaldo S. Queiroz , Werner Rodejohann

Measurements of the ratio of $B \to K^* \mu \mu $ to $B \to K^* e e $ branching fractions, $R_{K^*}$, by the LHCb collaboration strengthen the hints from previous studies with pseudoscalar kaons, $R_K$, for the breakdown of lepton…

High Energy Physics - Phenomenology · Physics 2018-02-12 Gudrun Hiller , Ivan Nisandzic

Recently, several new experimental results of the test of lepton flavor universality (LFU) in $B\to D^{(\ast)}$ semi-leptonic decays were announced: the first result of $R_{D}$ from the LHCb Run 1 data, the first results of $R_{D}$ and…

High Energy Physics - Phenomenology · Physics 2024-10-11 Syuhei Iguro , Teppei Kitahara , Ryoutaro Watanabe

The $B$-physics experiments at LHCb, BaBar and Belle hint towards deviations from Lepton Flavor Universality in both the tree-level and loop-induced $B$ meson semileptonic decays. We propose a leptoquark model with light right-handed…

High Energy Physics - Phenomenology · Physics 2017-05-23 Olcyr Sumensari

Flavor symmetries that explain masses and mixings of the standard model fermions dictate flavor patterns for the couplings of scalar and vector leptoquarks to the standard model fermions. A generic feature is that couplings to…

High Energy Physics - Phenomenology · Physics 2017-01-04 Gudrun Hiller , Dennis Loose , Kay Schönwald

The observable $\mathcal{R} \left( D^{(*)} \right) = \mathcal{B}\left( B^{0}\to D^{(*)-} \tau^{+} \nu_{\tau} \right) / \mathcal{B}\left( B^{0}\to D^{(*)-} \mu^{+} \nu_{\mu} \right)$ is a probe for Lepton Universality violation, so it is…

High Energy Physics - Experiment · Physics 2019-08-14 Federico Betti

The measurements of the lepton flavor universality (LFU) in $\mathcal{B}({\bar{B}} \to D^{(\ast)} l \bar{\nu})$ indicate a significant deviation from the standard model prediction at a 3-4$\sigma$ level, revealing a violation of the LFU…

High Energy Physics - Phenomenology · Physics 2024-10-15 Syuhei Iguro , Teppei Kitahara

We address the presently reported significant flavor anomalies in the Kaon and $B$ meson systems such as the CP violating Kaon decay ($\epsilon'/\epsilon$) and lepton-flavor universality violation in $B$ meson decays…

High Energy Physics - Phenomenology · Physics 2018-12-04 Shinya Matsuzaki , Kenji Nishiwaki , Kei Yamamoto

At the back of succeeding measurements of anomalies in semileptonic decays at LHCb and several collider experiments hinting at the possible violation of lepton flavor universality, we undertake a concise review of theoretical foundations of…

High Energy Physics - Phenomenology · Physics 2023-03-14 Sonali Patnaik , Rajeev Singh

Motivated by the recent experimental progress on the $B$-meson decay anomalies (in particular the angular observables in $B\to K^\ast\mu\mu$), we rely on a simplified-model approach to study the prospects of vector leptoquarks in what…

High Energy Physics - Phenomenology · Physics 2021-12-20 C. Hati , J. Kriewald , J. Orloff , A. M. Teixeira

The concept of lepton flavour universality (LFU), according to which the three lepton families are equivalent except for their masses, is a cornerstone prediction of the Standard Model (SM). LFU can be violated in models beyond the SM by…

High Energy Physics - Experiment · Physics 2019-05-22 Elena Graverini