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

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Recently, the LHCb collaboration announced a preliminary result of the test of lepton flavor universality (LFU) in $B\to D^{(\ast)}$ semi-leptonic decays: $R_{D}^{\rm LHCb2022} = 0.441 \pm 0.089$ and $R_{D^{\ast}}^{\rm LHCb2022} = 0.281 \pm…

High Energy Physics - Phenomenology · Physics 2024-05-30 Syuhei Iguro , Teppei Kitahara , Ryoutaro Watanabe

The vector leptoquark representation, $U_\mu = (3,1,2/3)$, was recently identified as an exceptional single mediator model to address experimental hints on lepton flavour universality violation in semileptonic $B$-meson decays, both in…

High Energy Physics - Phenomenology · Physics 2017-12-20 Luca Di Luzio , Admir Greljo , Marco Nardecchia

Lepton flavor universality violating $B\to K\ell\ell$ and $K^*\ell\ell$ decays tentatively observed by LHCb can be explained by leptoquark exchange. We explore a simple model for the $B$ anomalies with a composite leptoquark from new strong…

High Energy Physics - Phenomenology · Physics 2018-01-31 James M. Cline

The measurements of the ratios $R_{K^{(*)}}$ along with $R_{D^{(*)}}$ hint towards lepton flavor non universality which is in disagreement with the standard model. In this work, we reanalyze the four new physics models, which are widely…

High Energy Physics - Phenomenology · Physics 2019-08-27 Ashutosh Kumar Alok , Jacky Kumar , Dinesh Kumar , Ruchi Sharma

The R_K measurement by LHCb suggests non-standard lepton non-universality (LNU) to occur in b -> s l+ l- transitions, with effects in muons rather than electrons. A number of other measurements of b -> s l+ l- transitions by LHCb and…

High Energy Physics - Phenomenology · Physics 2016-10-17 Diego Guadagnoli , Dmitri Melikhov , Meril Reboud

Leptoquarks have been suggested to solve a variety of discrepancies between the expected and observed phenomenon. In this paper, we investigate the effect of scalar leptoquarks on the lepton flavor violating B meson rare decays which…

High Energy Physics - Phenomenology · Physics 2019-01-10 Jin-Huan Sheng , Ru-Min Wang , Ya-Dong Yang

We revisit the possibilities of accommodating the experimental indications of the lepton flavor universality violation in $b$-hadron decays in the minimal scenarios in which the Standard Model is extended by the presence of a single…

High Energy Physics - Phenomenology · Physics 2021-09-22 Andrei Angelescu , Damir Bečirević , Darius A. Faroughy , Florentin Jaffredo , Olcyr Sumensari

Leptoquarks are prime candidates for explaining the intriguing hints for lepton flavour universality violation. In particular, the $SU(2)_L$ doublet of scalar leptoquarks $S_2$ is capable of providing an explanation for the tensions between…

High Energy Physics - Phenomenology · Physics 2022-07-05 Andreas Crivellin , Benjamin Fuks , Luc Schnell

LHCb found hints for physics beyond the standard model in $B\to K^*\mu^+\mu^-$, $B\to K^*\mu^+\mu^-/B\to K^*e^+e^-$ and $B_s\to\phi\mu^+\mu^-$. In addition, the BABAR results for $B\to D^{(*)}\tau\nu$ and the CMS excess in…

High Energy Physics - Phenomenology · Physics 2016-04-20 Andreas Crivellin

Significant deviations from Standard Model (SM) predictions have been observed in $ b \to s \mu^+ \mu^-$ decays and in the muon $g-2$. Scalar leptoquark extensions of the SM are known to be able to address these anomalies, but generically…

High Energy Physics - Phenomenology · Physics 2021-10-15 Admir Greljo , Peter Stangl , Anders Eller Thomsen

We present a thorough investigation of the vector leptoquark hypothesis for a combined explanation of the $B$-physics anomalies. We analyze this hypothesis from a twofold perspective, taking into account recent results from $B$-physics…

High Energy Physics - Phenomenology · Physics 2019-07-31 Claudia Cornella , Javier Fuentes-Martin , Gino Isidori

We interpret the recent hints for lepton flavor universality violation in rare $B$ meson decays. Based on a model-independent effective Hamiltonian approach, we determine regions of new physics parameter space that give a good description…

High Energy Physics - Phenomenology · Physics 2018-05-04 Wolfgang Altmannshofer , Peter Stangl , David M. Straub

Inspired by the recent hints of lepton flavor universality violation in $b\to s\ell\ell$ and $b\to c\ell\nu$ transitions, we study lepton flavor violating exclusive $\Lambda_b\to\Lambda\ell_1^+\ell_2^-$ ($\ell_1\neq \ell_2$) decay, which is…

High Energy Physics - Phenomenology · Physics 2019-12-24 Diganta Das

The LHCb Collaboration's measurement of R_K = B(B+ -> K+ mu+ mu-)/B(B+ -> K+ e+e-) lies 2.6 sigma below the Standard Model prediction. Several groups suggest this deficit to result from new lepton non-universal interactions of muons. But…

High Energy Physics - Phenomenology · Physics 2015-03-11 Sheldon L. Glashow , Diego Guadagnoli , Kenneth Lane

Very recently the LHCb experiment released the first measurement of the ratio $R(\Lambda_c) = {\rm BR}(\Lambda_b \to \Lambda_c\tau\bar{\nu}_\tau)/{\rm BR}(\Lambda_b \to \Lambda_c\mu\bar{\nu}_\mu)$. Moreover, the BABAR experiment reported a…

High Energy Physics - Phenomenology · Physics 2023-02-21 Cristian H. García-Duque , J. M. Cabarcas , J. H. Muñoz , Néstor Quintero , Eduardo Rojas

More than $3\sigma$ deviations from the standard model are observed in the angular observable $P'_5$ of $B\to K^* \mu^+ \mu^-$ and muon $g-2$. To resolve these anomalies, we extend the standard model by adding two leptoquarks. It is found…

High Energy Physics - Phenomenology · Physics 2016-12-07 Chuan-Hung Chen , Takaaki Nomura , Hiroshi Okada

The latest measurements of rare $b\to s$ decays in the LHCb experiment have led to results in tension with the predictions of the standard model (SM), including a tentative indication of the violation of lepton flavor universality. Assuming…

High Energy Physics - Phenomenology · Physics 2015-08-31 Chao-Jung Lee , Jusak Tandean

Motivated by the recent LHCb announcement of a $3.1\sigma$ violation of lepton-flavor universality in the ratio $R_K=\Gamma(B\to K\mu^+\mu^-)/\Gamma(B\to K e^+ e^-)$, we present an updated, comprehensive analysis of the flavor anomalies…

High Energy Physics - Phenomenology · Physics 2021-09-28 Claudia Cornella , Darius A. Faroughy , Javier Fuentes-Martin , Gino Isidori , Matthias Neubert

During the past few years, hints of Lepton Flavour Universality (LFU) violation have been observed in $b \to c \tau \bar\nu$ and $b \to s \ell^+ \ell^-$ transitions. Recently, the $D^*$ and $\tau$ polarization fractions $P_L^{D^*}$ and…

High Energy Physics - Phenomenology · Physics 2019-06-26 Han Yan , Ya-Dong Yang , Xing-Bo Yuan

The flavor changing decays of heavy bottom quarks to the corresponding lighter quarks ($u$, $c$ and $s$) in various $B$-meson decays via charged current and neutral current semileptonic transitions have emerged as promising candidates to…

High Energy Physics - Phenomenology · Physics 2019-08-28 N Rajeev , Rupak Dutta , Suman Kumbhakar