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Related papers: Lepton flavor non-universality in the B-sector: a …

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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

We propose that three recent anomalies in $B$ meson decays, $R_{D^{(*)}}$, $R_K$, and $P_5'$, might be explained by a single vector leptoquark weak triplet state. The constraints on the parameter space are obtained by considering $t \to b…

High Energy Physics - Phenomenology · Physics 2016-03-08 Svjetlana Fajfer , Nejc Košnik

In order to simultaneously account for both $R_{D^{(\ast)}}$ and $R_{K^{(\ast)}}$ anomalies in $B$-decays, we consider an extension of the Standard Model by a single vector leptoquark field, and study how one can achieve the required lepton…

High Energy Physics - Phenomenology · Physics 2020-01-29 C. Hati , J. Kriewald , J. Orloff , A. M. Teixeira

Lepton flavor universality in the Standard Model and hints of its violation in neutral ($R_K$) and charged currents $(R_{D^{(*)}})$ in $B$ decays are presented. We discuss model independent features as well as several leptoquark scenarios…

High Energy Physics - Phenomenology · Physics 2016-10-04 Nejc Kosnik

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

There are four models of tree-level new physics (NP) that can potentially explain the $b\to s \mu^+ \mu^-$ and $b \to c\ell \bar \nu$ anomalies simultaneously. They are the S3, U3, and U1 leptoquarks and a standard-model-like triplet vector…

High Energy Physics - Phenomenology · Physics 2019-07-02 Jacky Kumar

Recently reported anomalies in various $B$ meson decays and also in the anomalous magnetic moment of muon $(g-2)_\mu$ motivate us to consider a particular extension of the standard model incorporating new interactions in lepton and quark…

High Energy Physics - Phenomenology · Physics 2023-01-18 Kayoung Ban , Yongsoo Jho , Youngjoon Kwon , Seong Chan Park , Seokhee Park , Po-Yan Tseng

Present measurements of b->c tau nu and b->u tau nu transitions differ from the standard model predictions of lepton flavor universality by almost 4sigma. We examine new physics interpretations of this anomaly. An effective field theory…

High Energy Physics - Phenomenology · Physics 2013-01-04 Svjetlana Fajfer , Jernej F. Kamenik , Ivan Nisandzic , Jure Zupan

We analyze the unparticle effects on the lepton flavor universality violating ratios in $b\to s$ transition, $R(K^{(*)})$. We concentrate on the vector unparticles which contribute to the relevant Wilson coefficients $C_{9,10}$. New effects…

High Energy Physics - Phenomenology · Physics 2023-02-22 Jong-Phil Lee

Building on our recent proposal to explain the experimental hints of new physics in $B$ meson decays within the framework of Pati-Salam quark-lepton unification, through the interactions of the $(3,1)_{2/3}$ vector leptoquark, we construct…

High Energy Physics - Phenomenology · Physics 2019-03-22 Bartosz Fornal , Sri Aditya Gadam , Benjamin Grinstein

There are four models of tree-level new physics (NP) that can potentially simultaneously explain the $b \to s \mu^+ \mu^-$ and $b \to c \tau^- {\bar\nu}$ anomalies. They are the S3, U3 and U1 leptoquarks (LQs), and a triplet of SM-like…

High Energy Physics - Phenomenology · Physics 2019-01-09 Jacky Kumar , David London , Ryoutaro Watanabe

Even though the LHC searches did not unveil the new physics particles so far, LHCb hints towards deviations from lepton flavor universality in exclusive decays based on the transition $b\to s\ell\ell$. In this proceeding, we present a new…

High Energy Physics - Phenomenology · Physics 2017-10-25 Olcyr Sumensari

LHCb has reported deviations from the Standard Model in $b\to s\mu^+\mu^-$ transitions for which a new neutral gauge boson is a prime candidate for an explanation. As this gauge boson has to couple in a flavour non-universal way to muons…

High Energy Physics - Phenomenology · Physics 2015-09-25 Andreas Crivellin , Lars Hofer , Joaquim Matias , Ulrich Nierste , Stefan Pokorski , Janusz Rosiek

Lepton flavor universality can be tested through the ratio of semileptonic $B$ meson decays and leptonic $\Upsilon$ meson decays, with $\Upsilon \equiv \Upsilon(nS)$ ($n=1,2,3$). For the charged-current transitions $b \to…

High Energy Physics - Phenomenology · Physics 2021-04-22 Cristian H. García-Duque , J. H. Muñoz , Néstor Quintero , Eduardo Rojas

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

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

We have investigated $B \to (K,K^*)(l\bar l,\nu\bar\nu)$ decay channels and predicted some form factor dependent observables (e.g. branching ratio, forward-backward asymmetry and lepton polarization asymmetry) considering new physics…

High Energy Physics - Phenomenology · Physics 2019-12-06 P. Maji , P. Nayek , S. Sahoo

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

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

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
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