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Related papers: Lepton flavour violating B meson decays via scalar…

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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

The measurements of the ratios $R_{K^{(*)}}$ along with $R_{D^{(*)}}$ hint towards lepton flavor non universality which is in disagreement with the standard model. In this work, we reanalyze the four new physics models, which are widely…

High Energy Physics - Phenomenology · Physics 2019-08-27 Ashutosh Kumar Alok , Jacky Kumar , Dinesh Kumar , Ruchi Sharma

We make an evaluation of the lepton flavor violating (LFV) decays $\tau \to \ell (V^0, P^0)$, where $\ell=e$ or $\mu$ and $V^0(P^0)$ is a neutral vector (pseudo-scalar) meson, in the context of unparticle physics. The constraints are…

High Energy Physics - Phenomenology · Physics 2009-06-19 Zuo-Hong Li , Ying Li , Hong-Xia Xu

The deviations of $B$-meson decays measured in $R_{D^{(*)}}^{\tau\ell}$ and $R_{K^{(*)}}^{\mu e}$ can be explained by the presence of two scalar leptoquarks, a singlet $S_1$ and a triplet $S_3$, mostly coupled to the third generation. We…

High Energy Physics - Phenomenology · Physics 2021-06-16 Leandro Da Rold , Federico Lamagna

Recent hints for lepton-universality violation in $b\to c\ell\nu$ and $b\to s\ell\ell$ transitions could imply the existence of lepton-flavour violating $b$ decays. The LHCb experiment is well suited for the search for these decays due to…

High Energy Physics - Experiment · Physics 2018-09-19 Luca Pescatore

We present a study on the impact of scalar leptoquarks on the semileptonic decays of $ \Lambda_b$, $\Sigma_b $ and $\Xi_b $. To this end, we calculate the differential branching ratio and lepton forward-backward asymmetry defining the…

High Energy Physics - Phenomenology · Physics 2017-09-06 K. Azizi , A. T. Olgun , Z. Tavukoglu

The measurements of rare leptonic and semi-leptonic B decays performed at the LHC, not showing any significant deviations from the Standard Model expectations, put strong constraints on new physics. A brief account of the impact of recent…

High Energy Physics - Phenomenology · Physics 2013-05-27 David M. Straub

The $R_{K^{(*)}}$ anomaly can be explained by tree level exchange of leptoquarks. We study the consequences of subjecting these models to the principle of minimal flavor violation (MFV). We consider MFV in the linear regime, and take the…

High Energy Physics - Phenomenology · Physics 2017-12-06 Daniel Aloni , Avital Dery , Claudia Frugiuele , Yosef Nir

Hints of lepton flavor violation have been observed by LHCb in the rate of the decay $B\to K\mu^+\mu^-$ relative to that of $B\to K e^+e^-$. This can be explained by new scalars and fermions which couple to standard model particles and…

High Energy Physics - Phenomenology · Physics 2018-06-27 James M. Cline , Jonathan M. Cornell

An analysis of charm mesons decaying semileptonically via Flavor Changing Neutral Currents is presented. We calculate the Wilson coefficients within the Standard Model. A window in the decay distribution, where physics beyond the Standard…

High Energy Physics - Phenomenology · Physics 2015-10-05 Stefan de Boer

We investigate the phenomenology of light GeV-scale fermionic dark matter in $U(1)_{L_\mu - L_{\tau}}$ gauge extension of the Standard Model. Heavy neutral fermions alongside with a $S_1(\overline{3}$,$1$,$1/3$) scalar leptoquark and an…

High Energy Physics - Phenomenology · Physics 2022-02-09 Shivaramakrishna Singirala , Suchismita Sahoo , Rukmani Mohanta

Upcoming experiments will improve the reach for the lepton flavour violating (LFV) processes $\mu \to e \gamma$, $\mu \to e \bar{e} e$ and $\mu A \to e A$ by orders of magnitude. We investigate whether this upcoming data could rule out some…

High Energy Physics - Phenomenology · Physics 2024-01-18 Marco Ardu , Sacha Davidson , Stéphane Lavignac

We predict the contribution of scalar unparticle to the branching ratios of the lepton flavor conserving Z -> l^+ l^- decays and we study the discrepancy between the experimental and the QED corrected standard model branching ratios. We…

High Energy Physics - Phenomenology · Physics 2009-03-12 E. Iltan

We study the lepton flavor violation (LFV) in tau decays in the framework of the supersymmetric seesaw mechanism with nonholomorphic terms for the lepton sector at a large $\tan\beta$. In particular, we analyze two new decay modes $\tau\to…

High Energy Physics - Phenomenology · Physics 2008-11-26 Chuan-Hung Chen , Chao-Qiang Geng

We make a comprehensive study of vector-like fermionic dark matter and flavor anomalies in a simple extension of standard model. The model is added with doublet vector-like fermions of quark and lepton types, and also a…

High Energy Physics - Phenomenology · Physics 2021-12-09 Suchismita Sahoo , Shivaramakrishna Singirala , Rukmani Mohanta

We perform a comprehensive analysis of neutrinoless double beta decay and its interplay with low-energy flavor observables in a radiative neutrino mass model with scalar leptoquarks $S_1(\bar{3},1,1/3)$ and $\widetilde{R}_2(3,2,1/6)$. We…

High Energy Physics - Phenomenology · Physics 2025-01-13 P. S. Bhupal Dev , Srubabati Goswami , Chayan Majumdar , Debashis Pachhar

Rare decays mediated by $b \to s \nu \bar \nu$ transitions have been reported by the Belle II experiment. The branching ratio of the decay $B^+ \to K^+ \nu \bar \nu$ is found to be enhanced with respect to the standard model value. If taken…

High Energy Physics - Phenomenology · Physics 2023-12-15 Rigo Bause , Hector Gisbert , Gudrun Hiller

Rare flavour-changing neutral-current transitions of the type $s \to d \ell^+\ell^-(\nu\bar\nu)$ and $b \to s \ell^+\ell^-(\nu\bar\nu)$ are analysed in supersymmetric extensions of the Standard Model with generic flavour couplings. It is…

High Energy Physics - Phenomenology · Physics 2007-05-23 Gino Isidori

We address the $B$-physics anomalies within a two scalar leptoquark model. The low-energy flavor structure of our set-up originates from two $SU(5)$ operators that relate Yukawa couplings of the two leptoquarks. The proposed scenario has a…

High Energy Physics - Phenomenology · Physics 2018-09-12 Damir Bečirević , Ilja Doršner , Svjetlana Fajfer , Nejc Košnik , Darius A. Faroughy , Olcyr Sumensari

We study the phenomenology of a supersymmetric left-right model, assuming minimal supergravity boundary conditions. Both left-right and (B-L) symmetries are broken at an energy scale close to, but significantly below the GUT scale. Neutrino…

High Energy Physics - Phenomenology · Physics 2011-01-27 J. N. Esteves , M. Hirsch , W. Porod , J. C. Romao , F. Staub , A. Vicente