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Related papers: LHCb anomalies from a natural perspective

200 papers

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

Some anomalies in the processes $b\to s\ell\ell$ ($\ell=\mu,e$) and $b\to c \ell\bar\nu_\ell$ ($\ell=\tau,\mu,e$), in particular in the observables $R_K$ and $R_{D^{(\ast)}}$, have been found by the BaBar, LHCb and Belle Collaborations,…

High Energy Physics - Phenomenology · Physics 2017-09-13 Eugenio Megias , Mariano Quiros , Lindber Salas

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

In view of both the latest LHCb measurement of $R_{K^{(*)}}$ and the new $2.8\sigma$ deviation reported by Belle II on $B^{+}\to K^{+}\nu\bar{\nu}$ decays, we present a fit to the $B$ meson anomalies for various one and two dimensional…

High Energy Physics - Phenomenology · Physics 2024-02-19 Peter Athron , R. Martinez , Cristian Sierra

I present a model addressing coherently the naturalness problem of the electroweak scale and the observed pattern of deviations from the Standard Model in semi-leptonic decays of $B$ mesons. The Higgs and the two scalar leptoquarks…

High Energy Physics - Phenomenology · Physics 2018-07-23 David Marzocca

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

Recently, the LHCb collaboration has reported the excesses in the $b \to s ll$ processes. One of the promising candidates for new physics to explain the anomalies is the extended Standard Model (SM) with vector-like quarks and leptons. In…

High Energy Physics - Phenomenology · Physics 2017-11-08 Junichiro Kawamura , Shohei Okawa , Yuji Omura

There are indications of a possible breakdown of the standard model, suggesting that $\tau$ lepton interactions violate flavor universality. BABAR, Belle and LHCb report high ratios of $B\to D^{(*)}\tau\nu$. There are long-standing excesses…

High Energy Physics - Phenomenology · Physics 2016-04-13 James M. Cline

In recent times, several hints of lepton non-universality have been observed in semileptonic $B$ meson decays, both in the charged-current ($b \to c l \bar \nu_l$) and neutral-current ($b \to s ll $) transitions. Motivated by these…

High Energy Physics - Phenomenology · Physics 2019-01-16 Atasi Ray , Suchismita Sahoo , Rukmani Mohanta

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

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

Motivated by renewed evidence for new physics in $b \to s\ell\ell$ transitions in the form of LHCb's new measurements of theoretically clean lepton-universality ratios and the purely leptonic $B_s\to\mu^+\mu^-$ decay, we quantify the…

High Energy Physics - Phenomenology · Physics 2021-10-20 Li-Sheng Geng , Benjamín Grinstein , Sebastian Jäger , Shuang-Yi Li , Jorge Martin Camalich , Rui-Xiang Shi

We explore a scenario of New Physics entering the description of $B\to K^{(\ast )} \mu \mu$ decay through couplings to the operators ${\cal O}_{9,10}^\prime$, satisfying $C_9^\prime = - C_{10}^\prime$. From the current data on ${\cal…

High Energy Physics - Phenomenology · Physics 2016-08-10 Damir Bečirević , Svjetlana Fajfer , Nejc Košnik

A recent proposal for explaining discrepancies in angular observables in the rare decay B --> K*mu+mu- with a gauged L_mu - L_tau current carried with it the prediction of lepton flavor universality violation in related B-meson decays. This…

High Energy Physics - Phenomenology · Physics 2015-10-21 Wolfgang Altmannshofer , Itay Yavin

Non-leptonic $B^0_s \rightarrow D_s^{\pm} K^{\mp}$ transitions are particularly interesting processes to test the Standard Model. As these decays occur via pure tree diagrams, they allow a theoretically clean determination of the angle…

High Energy Physics - Phenomenology · Physics 2022-03-28 Robert Fleischer , Eleftheria Malami

Supersymmetric B-L extension of the Standard Model (SM) is one of the best candidate for physics beyond the SM that accounts for TeV scale seesaw mechanism and provides an attractive solution for the Higgs naturalness problem. We analyze…

High Energy Physics - Phenomenology · Physics 2013-05-29 Shaaban Khalil

The ATLAS, CMS and LHCb experiments will perform extensive searches for physics Beyond the Standard Model (BSM). The investigation of decays of beauty hadrons represents an alternative and complementary approach to the direct BSM searches.…

High Energy Physics - Experiment · Physics 2011-02-14 Nicola Serra

We study the possibility of explaining the recently found anomalies in B-meson decays within scenarios with a composite Higgs boson. This class of models provides a natural way to fit the experimental results, interpreting the anomalies as…

High Energy Physics - Phenomenology · Physics 2017-05-31 Eugenio Megias , Giuliano Panico , Oriol Pujolas , Mariano Quiros

Precision measurements in weak decays of heavy flavored hadrons can test in unique ways our understanding of the fundamental interactions and of the observed baryon asymmetry in the Universe. The high sensitivity of such decays to…

High Energy Physics - Experiment · Physics 2022-09-19 Angelo Di Canto , Stefan Meinel

The LHCb collaboration has very recently released a new study of $B^+ \to K^{+} \ell^+ \ell^-$ and $B \to K^{*0} \ell^+ \ell^-$ ($\ell = e,\mu$) decays, testing lepton universality with unprecedented accuracy using the whole Run 1 and 2…

High Energy Physics - Phenomenology · Physics 2023-04-05 Marco Ciuchini , Marco Fedele , Enrico Franco , Ayan Paul , Luca Silvestrini , Mauro Valli