English
Related papers

Related papers: Beyond the Standard Model with Lepton Flavor Unive…

200 papers

We propose renormalizable models of new physics that can explain various anomalies observed in decays of B-mesons to electron and muon pairs. The new physics states couple to linear combinations of Standard Model fermions, yielding a…

High Energy Physics - Phenomenology · Physics 2016-07-20 Ben Gripaios , M. Nardecchia , S. A. Renner

Extant anomalies in several semileptonic $B$-meson decays argue for physics beyond the Standard Model. Measurements of both neutral-current decays (such as $R_K$, $R_{K^*}$ and $B_s\rightarrow \phi\mu\mu$) as well as charged-current ones-…

High Energy Physics - Phenomenology · Physics 2019-10-23 Debajyoti Choudhury , Nilanjana Kumar , Anirban Kundu

We analyze in detail the angular distributions in $\bar{B}\to D^*\ell \bar\nu$ decays, with a focus on lepton-flavour non-universality. We investigate the minimal number of angular observables that fully describes current and upcoming…

High Energy Physics - Phenomenology · Physics 2021-11-24 Christoph Bobeth , Marzia Bordone , Nico Gubernari , Martin Jung , Danny van Dyk

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

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

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

The observation of neutrino oscillation as well as the recent experimental result on lepton flavor universality (LFU) violation in $B$ meson decays are indications of new physics beyond the Standard Model. Many theoretical models, which are…

High Energy Physics - Phenomenology · Physics 2017-02-01 Soumya C. , R. Mohanta

We report on recent results obtained by the Belle II experiment related to searches for beyond-the-standard-model physics. The $B$ meson decay data sample used corresponds to an integrated luminosity of $L = 189$ fb$^{-1}$. In recent years,…

High Energy Physics - Experiment · Physics 2023-08-15 Roberta Volpe , Belle II Collaboration

We explore the possibility that lepton family numbers and baryon number are such good symmetries of Nature because they are the global remnant of a spontaneously broken gauge symmetry. An almost arbitrary linear combination of these…

High Energy Physics - Phenomenology · Physics 2020-01-15 Wolfgang Altmannshofer , Joe Davighi , Marco Nardecchia

We study the Standard Model and the new physics predictions for the lepton-flavour-universality violating (LFUV) ratios in various $b\to s \ell^+\ell^-$ channels with scalar, pseudoscalar, vector, axial-vector, and $\Lambda$ baryon final…

High Energy Physics - Phenomenology · Physics 2022-03-31 Faisal Munir Bhutta , Zhuo-Ran Huang , Cai-Dian Lü , M. Ali Paracha , Wenyu Wang

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

Lepton flavour violation (LFV) naturally occurs in many new physics models, specifically in those explaining the $B$ anomalies. While LFV has already been studied for mesonic decays, it is important to consider also baryonic decays mediated…

High Energy Physics - Phenomenology · Physics 2021-09-15 Marzia Bordone , Muslem Rahimi , K. Keri Vos

Recently hints of lepton flavor non-universality emerged when the BaBar Collaboration observed deviations from the standard model predictions in $R(D^{(*)}) \equiv {\cal B}({\bar B} \to D^{(*)+} \tau^- {\bar\nu}_\tau) / {\cal B}({\bar B}…

High Energy Physics - Phenomenology · Physics 2015-06-10 Shanmuka Shivashankara , Wanwei Wu , Alakabha Datta

LHCb found hints for physics beyond the Standard Model (SM) in $B\to K^*\mu^+\mu^-$, $R(K)$ and $B_s\to\phi\mu^+\mu^-$. These intriguing hints for NP have recently been confirmed by the LHCb measurement of $R(K^*)$ giving a combined…

High Energy Physics - Phenomenology · Physics 2017-06-06 Andreas Crivellin

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

We analyse the recent hints of Lepton Flavor Universality violations in semi-leptonic $B$ decays within a general EFT based on a $U(2)^n$ flavor symmetry acting on the light generations of SM fermions. We analyse in particular the…

High Energy Physics - Phenomenology · Physics 2017-08-02 Marzia Bordone , Gino Isidori , Sokratis Trifinopoulos

Motivated by recent experimental measurements on flavour physics, in tension with Standard Model predictions, we perform an updated analysis of New Physics violating Lepton Flavour Universality, by using the effective Lagrangian approach…

High Energy Physics - Phenomenology · Physics 2019-09-04 Jorge Alda , Jaume Guasch , Siannah Peñaranda

Lepton Flavor Universality Violation (LFUV) in $b\rightarrow s l^+ l^-$ processes is investigated in the context of a 331 model. It is shown that in order to explain the experimentally observed deviations from the Standard Model in these…

High Energy Physics - Phenomenology · Physics 2020-03-09 Soumia Lebbal , Noureddine Mebarki , Jamal Mimouni

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

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