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Related papers: New Physics in Flavour Observables

200 papers

The origin of flavour and CP violation is among the most important open questions in particle physics. Imminent results from the LHC as well as planned dedicated flavour physics experiments might help to shed light on this puzzle. This talk…

High Energy Physics - Phenomenology · Physics 2022-03-02 David M. Straub

The anomalies in the measurements of observables involving $b \to s \mu\mu$ decays, namely $R_K$, $R_{K^*}$, $P_5^{\prime}$, and $B_s^\phi$, may be addressed by adding lepton-universality-violating new physics contributions to the effective…

High Energy Physics - Phenomenology · Physics 2021-03-25 Ashutosh Kumar Alok , Amol Dighe , Shireen Gangal , Dinesh Kumar

Recently two hints for new physics have emerged: The B_s mixing phase phi_s and the rate of D_s -> (mu,tau) nu exposing a discrepancy of \sim 3 sigma and 3.8 sigma deviation from the Standard Model respectively. Moreover the difference of…

High Energy Physics - Phenomenology · Physics 2008-07-22 Roman Zwicky

Extending the Standard Model with higher-dimensional operators in an effective-field-theory (EFT) approach provides a systematic framework to study new-physics (NP) effects from a bottom-up perspective, as long as the NP scale is…

High Energy Physics - Phenomenology · Physics 2020-01-29 Marzia Bordone , Oscar Catà , Thorsten Feldmann

The $R_{D^{(\ast)}}$ anomaly is one of the most intriguing experimental results in particle physics today. Experiments such as BaBar, Belle and LHCb have measured a consistent tension with the standard model (SM). We study several…

High Energy Physics - Phenomenology · Physics 2023-04-26 Andrés Flórez , José D. Ruiz Álvarez , Tomas Atehortua Garces

We investigate a gauge extension of the Standard Model in light of the observed hints of lepton universality violation in $b \to c \ell \nu$ and $b \to s \ell^+ \ell^-$ decays at BaBar, Belle and LHCb. The model consists of an extended…

High Energy Physics - Phenomenology · Physics 2016-12-19 Sofiane M. Boucenna , Alejandro Celis , Javier Fuentes-Martin , Avelino Vicente , Javier Virto

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

Recently, several indications of lepton non-universality observables have been perceived in semileptonic $B$ meson decay processes, both in the neutral-current ($b \to s ll $) and charged-current ($b \to c l \bar \nu_l$) transitions.…

High Energy Physics - Phenomenology · Physics 2025-07-16 Aishwarya Bhatta , Rukmani Mohanta

Since 2013, the LHCb collaboration has reported on the measurement of several observables associated to $b \to s$ transitions, finding various deviations from their predicted values in the Standard Model. These include a set of deviations…

High Energy Physics - Phenomenology · Physics 2018-10-11 Avelino Vicente

We consider possible new physics contributions to b\to s l^+ l^- assuming the new physics modifies (chromo)magnetic and electric form factors in b\to s \gamma^* and b\to s g with the same chirality structure as in the standard model.…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yeong Gyun Kim , P. Ko , Jae Sik Lee

Semileptonic and purely leptonic decays of B meson to $\tau$, such as $B\to D^{(\ast)}\tau\nu_{\tau}$ and $B\to\tau\nu_\tau$ are studied. Recognizing that there already were some weak hints of possible deviations from the SM in the…

High Energy Physics - Phenomenology · Physics 2016-11-15 Soumitra Nandi , Sunando K. Patra , Amarjit Soni

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

In the Standard Model (SM), the coupling of the electroweak gauge bosons to the leptons is lepton flavour universal. Tests of this property constitute sensitive probes for new physics models that violate lepton flavour universality. Recent…

High Energy Physics - Experiment · Physics 2018-07-01 Christoph Langenbruch

The recent measurements of lepton flavor university (LFU) violating observables in semileptonic $b \to c \ell \bar{\nu} $ and $b\to s\ell^+ \ell^-$ transitions by various experiments exhibit $(2-3)\sigma$ deviations from their corresponding…

High Energy Physics - Phenomenology · Physics 2021-06-08 Suman Kumbhakar , Rukmani Mohanta

In this work, we revisit the possible new physics (NP) solutions by analyzing the observables associated with $B\to D^{(\ast)}\tau\bar{\nu}_{\tau}$ decays. To explore the structure of new physics, the form factors of $B\to D^{(\ast)}$…

High Energy Physics - Phenomenology · Physics 2025-07-08 Zhuo-Ran Huang , Faisal Munir Bhutta , Nimra Farooq , M. Ali Paracha , Ying Li

In recent times, several discrepancies at the level of $(2-3)\sigma$ have been observed in the decay processes mediated by flavour changing neutral current (FCNC) transitions $b \to s \ell^+ \ell^-$, which may be considered as the…

High Energy Physics - Phenomenology · Physics 2021-08-03 Aishwarya Bhatta , Rukmani Mohanta

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

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

The current world averages of the ratios $R_{D^{(*)}}$ are about $4\sigma$ away from their Standard Model prediction. These measurements indicate towards the violation of lepton flavor universality in $b\rightarrow c\,l\,\bar{\nu}$ decay.…

High Energy Physics - Phenomenology · Physics 2020-02-18 Suman Kumbhakar , Ashutosh Kumar Alok , Dinesh Kumar , S Uma Sankar

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