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Related papers: Looking for the effects of New Physics in the $\La…

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We analyze the decays $K\to\pi\ell\nu$ and $P\to\ell\nu$ ($P=K,\pi$, $\ell=e,\,\mu$) using a low-energy Effective-Field-Theory approach to parametrize New Physics and study the complementarity with baryon $\beta$ decays. We then provide a…

High Energy Physics - Phenomenology · Physics 2017-02-01 Martín González-Alonso , Jorge Martin Camalich

We benefit from a recent lattice determination of the full set of vector, axial and tensor form factors for the $\Lambda_b\to \Lambda^*_c(2595)\tau\bar\nu_\tau$ and $\Lambda^*_c(2625)\tau\bar\nu_\tau$ semileptonic decays to study the…

High Energy Physics - Phenomenology · Physics 2022-09-28 Meng-Lin Du , Neus Penalva , Eliecer Hernández , Juan Nieves

The most recent measurements of the observables $R_{D^{(*)}}$ are in tension with the Standard Model offering hints of New Physics in $b\rightarrow c \ell \bar{\nu}_{\ell}$ transitions. Motivated by these results, in this work we present an…

High Energy Physics - Phenomenology · Physics 2018-12-14 Giovanni Banelli , Robert Fleischer , Ruben Jaarsma , Gilberto Tetlalmatzi-Xolocotzi

In this proceeding we will review the current theoretical status of rare $B$ decays. These decays are indeed excellent indirect probes for New Physics searches, and in the current situation where no new states have been directly observed at…

High Energy Physics - Phenomenology · Physics 2024-02-07 Marco Fedele

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

We extend the Standard Model with the general effective Hamiltonian for the quark level transition $c \to s \ell \nu$ with a complete set of four fermion operators including right-handed neutrinos. The current experimental measurements in…

High Energy Physics - Phenomenology · Physics 2025-04-10 Priyanka Boora , Dinesh Kumar , Kavita Lalwani

We consider new-physics (NP) contributions to the decay t -> b \bar{b} c. We parameterize the NP couplings by an effective Lagrangian consisting of 10 Lorentz structures. We show that the presence of NP can be detected through the…

High Energy Physics - Phenomenology · Physics 2013-05-29 Ken Kiers , Tal Knighton , David London , Matthew Russell , Alejandro Szynkman , Kari Webster

In the companion paper it was shown that there are six observables in $gg\to t \bar t \to (b \bar b c) (\bar b \ell \bar \nu)$ that can be used to reveal the presence of new physics (NP) in $t \to b \bar b c$. In the present paper we…

High Energy Physics - Phenomenology · Physics 2015-10-02 Pratishruti Saha , Ken Kiers , David London , Alejandro Szynkman

The discovery of New Physics, using weak decays of mesons is difficult due to intractable strong interaction effects needed to describe it. We show how the multitude of "related observables" obtained from B\to K^* \ell^+\ell^-, can provide…

High Energy Physics - Phenomenology · Physics 2012-02-24 Diganta Das , Rahul Sinha

Although direct detection of new particles will be the main focus of the LHC, indirect New Physics searches are expected to provide useful complementary information. In particular, precision measurements of rare processes occurring in…

High Energy Physics - Experiment · Physics 2008-05-19 A. Hicheur

The rare decays mediated by flavor-changing neutral current processes, such as $b \to s \ell^{+}\ell^{-}$, provide powerful probes of the Standard Model and potential windows into new physics. Particularly, the angular observables in these…

High Energy Physics - Phenomenology · Physics 2026-01-27 Rana Khan , Faisal Munir Bhutta , Ishtiaq Ahmed , M. Jamil Aslam

The most sensitive experimental searches for $D-\bar D$ mixing use $D^0 \to K^+ \pi^-$ decays. It is often assumed that effects of New Physics and, in particular, CP violation, can appear through the mixing, while the $c \to d u \bar s$…

High Energy Physics - Phenomenology · Physics 2009-10-31 Sven Bergmann , Yosef Nir

We perform a comprehensive study of the impact of new-physics operators with different Lorentz structures on $\BDstarellnu$ decays, $(\ell = e, \mu, \tau $) involving the $b \to c l \nu_\ell$ transition. We present the full three angle and…

High Energy Physics - Phenomenology · Physics 2013-11-05 Murugeswaran Duraisamy , Alakabha Datta

We provide a comprehensive model-independent analysis of rare decays involving the b --> s transition to put constraints on dimension-six Delta(F)=1 effective operators. The constraints are derived from all the available up-to-date…

High Energy Physics - Phenomenology · Physics 2014-01-29 Wolfgang Altmannshofer , Paride Paradisi , David M. Straub

Inclusive semileptonic $B\to X_c \ell \bar{\nu}_\ell$ decays, where $\ell = \mu,e$, are by now standard candles in the determination of the CKM element $|V_{cb}|$. These determinations rely on the heavy-quark expansion and use moments of…

High Energy Physics - Phenomenology · Physics 2023-04-20 Matteo Fael , Muslem Rahimi , K. Keri Vos

The Belle Collaboration has measured the complete set of angular coefficient functions for the decays ${\bar B} \to D^*\,(D\,\pi)\,\ell\,{\bar \nu}_{\ell}$, where $\ell = e,\,\mu$, in four bins of the variable $w={m_B^2+m_{D^*}^2-q^2 \over…

High Energy Physics - Phenomenology · Physics 2024-10-22 Nicola Losacco

We apply the formalism of amplitude symmetries to the angular distribution of the decays $B \to D^* \ell \nu$ for $\ell=e,\mu,\tau$. We show that the angular observables used to describe the distribution of this class of decays are not…

High Energy Physics - Phenomenology · Physics 2020-07-15 Marcel Algueró , Sébastien Descotes-Genon , Joaquim Matias , Martín Novoa-Brunet

Based on the standard model (SM) of particle physics, we study the decays $\Lambda_b \to \Lambda \ell^+ \ell^-$ in light of the available inputs from lattice and the data from LHCb. We fit the form-factors of this decay mode using the…

High Energy Physics - Phenomenology · Physics 2020-05-06 Srimoy Bhattacharya , Soumitra Nandi , Sunando Kumar Patra , Ria Sain

A comprehensive study of the impact of new-physics on different observables for $B_{s}\to \phi \ell^{+}\ell^{-}$ has been done. We examine the new physics models such as $Z^{\prime}$ and UED models, where the effects of new physics coming…

High Energy Physics - Phenomenology · Physics 2013-07-23 Ishtiaq Ahmed , M. Jamil Aslam , M. Ali Paracha

New physics effects on the $B^0-\bar{B}^0$ mixing and B-decay amplitudes are discussed. By a combined analysis, the model of new physics can be partially distinguished.It is emphasized that the extraction of unitarity angles $\beta$ and…

High Energy Physics - Phenomenology · Physics 2014-11-17 Y. F. Zhou , Y. L. Wu