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Related papers: Correlating Lepton Flavour (Universality) Violatio…

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In recent years, intriguing hints for the violation of Lepton Flavour Universality (LFU) have been accumulated in semileptonic $B$ decays, both in the neutral-current transitions $b\to s\ell^+\ell^-$ (i.e., $R_K$ and $R_{K^*}$) and the…

High Energy Physics - Phenomenology · Physics 2018-05-09 Bernat Capdevila , Andreas Crivellin , Sébastien Descotes-Genon , Lars Hofer , Joaquim Matias

In view of the emerging hints for the violation of lepton flavour universality in several $B$-meson decays, we conduct a model-independent study (effective field theory approach) of several well-motivated new physics scenarios. Taking into…

High Energy Physics - Phenomenology · Physics 2021-04-02 J. Kriewald , C. Hati , J. Orloff , A. M. Teixeira

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

The evidence for Lepton Flavour Universality (LFU) violation in semileptonic $B$-decays has been rising over the past few years. Relying on generic effective field theory (EFT) results, it has been shown that models addressing the…

High Energy Physics - Phenomenology · Physics 2022-07-25 Lukas Allwicher , Nudžeim Selimović

We study the effect of scalar leptoquarks in the lepton flavour violating $B$ meson decays induced by the flavour changing transitions $b \to q l_i^+ l_j^-$ with $q=s,d$. In the standard model these transitions are extremely rare as they…

High Energy Physics - Phenomenology · Physics 2016-06-08 Suchismita Sahoo , Rukmani Mohanta

One of the fundamental predictions of the Standard Model is Lepton Flavour Universality. Any deviation from this prediction would indicate the existence of physics beyond the Standard Model. Recent LHCb measurements present a pattern of…

High Energy Physics - Phenomenology · Physics 2018-08-21 Yoav Afik , Jonathan Cohen , Eitan Gozani , Enrique Kajomovitz , Yoram Rozen

Ratios of branching fractions of semileptonic B decays, $(B \to H \mu \mu)$ over $(B \to H ee)$ with $H=K, K^*,X_s, K_0(1430), \phi, \ldots$ are sensitive probes of lepton universality. In the Standard Model, the underlying flavor changing…

High Energy Physics - Phenomenology · Physics 2015-06-23 Gudrun Hiller , Martin Schmaltz

Leptoquarks are ubiquitous in several extensions of the Standard Model and seem to be able to accommodate the universality-violation-driven $B$-meson-decay anomalies and the $(g-2)_\mu$ discrepancy interpreted as deviations from the…

High Energy Physics - Phenomenology · Physics 2022-05-18 Tomas Husek , Kevin Monsalvez-Pozo , Jorge Portoles

The LHCb collaboration has recently presented their result on R_K = BR(B+ -> K+ mu+ mu-)/ BR(B+ -> K+ e+ e-) for the dilepton invariant mass bin m_{ll}^2 = 1-6 GeV^2 (l = mu, e). The measurement shows an intriguing 2.6 sigma deviation from…

High Energy Physics - Phenomenology · Physics 2015-06-22 Diptimoy Ghosh , Marco Nardecchia , S. A. Renner

Several experiments revealed intriguing hints for lepton flavor universality (LFU) violating new physics (NP) in semi-leptonic $B$ meson decays, mainly in $b \to c \tau \nu$ and $b \to s \ell^+ \ell^-$ transitions at the $3-5\,\sigma$…

High Energy Physics - Phenomenology · Physics 2019-06-05 Andreas Crivellin , Francesco Saturnino

Motivated by the recent measurement of the lepton flavour nonuniversality ratio $R_{K^*}$ by the LHCb Collaboration, we study the implications of vector leptoquarks on the observed anomalies associated with the $\bar B \to \bar K^* l^+ l^-$…

High Energy Physics - Phenomenology · Physics 2018-08-01 Suchismita Sahoo , Rukmani Mohanta

While the LHC has not directly observed any new particle so far, experimental results from LHCb, BELLE and BABAR point towards the violation of lepton flavour universality in $b\to s\ell^{+}\ell^{-}$ and $b\to c\ell\nu$. In this context,…

High Energy Physics - Phenomenology · Physics 2018-06-13 Dario Müller

The long persistent discrepancies in $b\,\to\,s\, \ell\, \ell$ quark level transitions continue to be the ideal platform for an indirect search of new physics that lies beyond the SM. The measurements of $R_K$, $R_{K^*}$, $P_5^{\prime}$,…

High Energy Physics - Phenomenology · Physics 2023-09-07 N Rajeev , Rupak Dutta

A number of measurements in decays induced by the semileptonic $b\to s$ and $b\to c$ transitions hint towards a possible role of new physics in both sectors. Motivated by these anomalies, we investigate the lepton flavor violating $B\to…

High Energy Physics - Phenomenology · Physics 2023-08-14 Suman Kumbhakar , Ria Sain , Juhi Vardani

Semileptonic charged current $b \to c l^- \overline{\nu}_l$ decays offer a compelling avenue to probe the limits of the Standard Model and investigate lepton flavor universality (LFU). While the SM maintains flavor universality, new physics…

High Energy Physics - Experiment · Physics 2023-05-16 Abhijit Mathad

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

Tests of lepton-universality as rate ratios in $b\to s \ell\ell$ transitions can be predicted very accurately in the Standard Model. The deficits with respect to expectations reported by the LHCb experiment in muon-to-electron ratios of the…

High Energy Physics - Phenomenology · Physics 2020-02-03 Li-Sheng Geng , Benjamín Grinstein , Sebastian Jäger , Jorge Martin Camalich , Xiu-Lei Ren , Rui-Xiang Shi

Recent anomalies in $B$-meson decays, such as deviations in $R_{D^{(*)}}$ and $B\to K\nu{\bar\nu}$, suggest possible lepton flavor universality violation and new exotic interactions. In this work, we explore these anomalies within a…

High Energy Physics - Phenomenology · Physics 2025-06-04 Bhubanjyoti Bhattacharya , Alakabha Datta , Gaber Faisel , Shaaban Khalil , Shibasis Roy

The long-standing anomaly in the anomalous magnetic moment of the muon indicates the presence of chirality violating new physics contributions. A possible solution involves scalar leptoquarks with left- and right-handed couplings to the top…

High Energy Physics - Phenomenology · Physics 2017-03-29 Estefania Coluccio Leskow , Andreas Crivellin , Giancarlo D'Ambrosio , Dario Müller

Motivated by the recent experimental progress on the $R_{D^{(\ast)}}$ and $R_{K^{(\ast)}}$ anomalies in $B$-decays, we consider an extension of the Standard Model by a single vector leptoquark field. We study how one can achieve the…

High Energy Physics - Phenomenology · Physics 2020-12-14 J. Kriewald , C. Hati , J. Orloff , A. M. Teixeira