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Related papers: R_b and New Physics: A Comprehensive Analysis

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The $B$-physics experiments at LHCb, BaBar and Belle hint towards deviations from Lepton Flavor Universality in both the tree-level and loop-induced $B$ meson semileptonic decays. We propose a leptoquark model with light right-handed…

High Energy Physics - Phenomenology · Physics 2017-05-23 Olcyr Sumensari

We examine the new physics sensitivity of the rare decay $\Lambda_b \to \Lambda \nu\bar\nu$ which can be accessible at future $Z$-pole machines like FCC-ee and CEPC. We find that the longitudinal polarization of $\Lambda_b$ baryons produced…

High Energy Physics - Phenomenology · Physics 2025-03-11 Wolfgang Altmannshofer , Sri Aditya Gadam , Kevin Toner

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

We discuss a model that can accommodate the $B$-physics anomalies, based on combining two scalar leptoquarks, $R_2$ and $S_3$, of mass $\mathcal{O}(1\,\mathrm{TeV})$, and that we proposed in our previous paper. We update the analysis of its…

High Energy Physics - Phenomenology · Physics 2022-06-22 Damir Bečirević , Ilja Doršner , Svjetlana Fajfer , Darius A. Faroughy , Florentin Jaffredo , Nejc Košnik , Olcyr Sumensari

We study $B \to K^* \rho$ modes that are analogues of the much studied $B\to K \pi$ modes with B decaying to two vector mesons instead of pseudoscalar mesons, using topological amplitudes in the quark diagram approach. We show how $B \to…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. S. Kim , Sechul Oh , Chandradew Sharma , Rahul Sinha , Yeo Woong Yoon

The recent measurement of $R_K$ at LHCb continues to support the hint of violation of lepton flavor universality. We perform a global fit for new physics in semileptonic $b\to s$ transitions using all the relevant data with a Bayesian…

High Energy Physics - Phenomenology · Physics 2019-06-21 Dinesh Kumar , Kamila Kowalska , Enrico Maria Sessolo

Tension between the Standard Model (SM) and data concerning $b \rightarrow s$ processes has become apparent. Most notoriously, concerning the $R_K$ ratio, which probes lepton non-universality in $b$ decays, and measurements involving the…

High Energy Physics - Phenomenology · Physics 2017-03-30 Isabel Garcia Garcia

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

After briefly reviewing the status of the $B$-physics anomalies, describing the challenges of building a scenario of physics beyond the Standard Model that can accommodate the observed departures from lepton flavor universality, I discuss a…

High Energy Physics - Phenomenology · Physics 2018-06-20 Damir Becirevic

The $B$ meson semileptonic modes to $\rho(770)$ and $a_1 (1260)$ are useful to pin down possible non Standard Model effects. The 4d differential $\bar B \to \rho(\pi \pi) \ell^- \bar \nu_\ell$ and $ \bar B \to a_1 (\rho \pi) \ell^- \bar…

High Energy Physics - Phenomenology · Physics 2019-11-06 P. Colangelo , F. De Fazio , F. Loparco

We show that by adding a single new scalar particle to the Standard Model, a TeV-scale leptoquark with the quantum numbers of a right-handed down quark, one can explain in a natural way three of the most striking anomalies of particle…

High Energy Physics - Phenomenology · Physics 2016-04-13 Martin Bauer , Matthias Neubert

We scrutinize the recently further strengthened hints for new physics in semileptonic $B$-meson decays, focusing on the 'clean' ratios of branching fractions $R_K$ and $R_{K^\ast}$ and examining to which pattern of new effects they point…

High Energy Physics - Phenomenology · Physics 2018-12-05 Adrián Carmona , Florian Goertz

The complementarity between results anticipated from SuperB with those from the LHC experiments is discussed here. SuperB can contribute to searches for new physics using indirect constraints via precision tests of the standard model. In…

High Energy Physics - Phenomenology · Physics 2015-06-04 Adrian Bevan

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

We present a simple analysis that allows us to extract the leading mass dependence of the dipole moment of matter fermions that might be induced by new physics. We present explicit results for the supersymmetric model with broken R-parity…

High Energy Physics - Phenomenology · Physics 2009-10-31 R. M. Godbole , S. Pakvasa , S. D. Rindani , X. Tata

We consider lepton-antilepton annihilation into a fermion-antifermion pair at variable c.m. energy. We propose for this process a simple parametrization of the virtual effects of the most general model of new physics of…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Beccaria , F. M. Renard , S. Spagnolo , C. Verzegnassi

We revisit the experimental and theoretical status of $B \to \rho l \bar{\nu}$ and $B \to \omega l \bar{\nu}$ decays. We perform a combined fit of averaged spectra from Belle and Babar measurements with prior light cone sum rule…

High Energy Physics - Phenomenology · Physics 2023-02-22 Florian U. Bernlochner , Markus T. Prim , Dean J. Robinson

We study the implications of possible off-peak measurements in the 1995 LEP run, in regard to probing physics beyond the Standard Model. To do so, we determine the accuracy with which various nonstandard couplings can be expected to be…

High Energy Physics - Phenomenology · Physics 2016-09-01 P. Bamert , C. P. Burgess , I. Maksymyk

In this article we investigate in detail the possibility of accounting for the $b\to s\ell^+\ell^-$ and $(g-2)_\mu$ anomalies via loop contributions involving with new scalars and fermions. For this purpose, we first write down the most…

High Energy Physics - Phenomenology · Physics 2022-10-12 Pere Arnan , Andreas Crivellin , Marco Fedele , Federico Mescia

Measuring the Higgs couplings accurately at colliders is one of the best routes for finding physics Beyond the Standard Model (BSM). If the measured couplings deviate from the SM predictions, then this would give rise to energy-growing…

High Energy Physics - Phenomenology · Physics 2022-07-06 Fayez Abu-Ajamieh