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Related papers: Constraining new physics in $b\to c\ell\nu$ transi…

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Current experimental information on the charm meson decay observables in which the $c\to s\ell\nu_\ell$ transitions occur is well compatible with the Standard Model predictions. Recent precise lattice calculations of the $D_s$ meson decay…

High Energy Physics - Phenomenology · Physics 2015-05-13 Svjetlana Fajfer , Ivan Nisandzic , Ursa Rojec

The $B\to K^*\mu\mu$ decay exhibits deviations with respect to Standard Model expectations and the measurement of the ratio $R_K$ hints at a violation of lepton-flavour universality in $B\to K\ell\ell$ transitions. Both effects can be…

High Energy Physics - Phenomenology · Physics 2017-09-13 Bernat Capdevila , Sebastien Descotes-Genon , Joaquim Matias , Javier Virto

These proceedings review the status of New Physics contributions to flavour violating $B$ decays. The anomalies in charged and neutral current $B$ decays related to lepton flavour universality violation have received a substantial amount of…

High Energy Physics - Phenomenology · Physics 2022-09-21 Monika Blanke

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

We study the $\bar{B}\to D(D^*) \ell^-\bar{\nu}_{\ell}$ decays based on the up-to-date available inputs from experiments and the lattice. First, we review the standard model (SM) predictions of the different observables associated with…

High Energy Physics - Phenomenology · Physics 2023-12-22 Ipsita Ray , Soumitra Nandi

Motivated by the recent hints of lepton flavour non-universality in $B$-meson semi-leptonic decays, we study the constraints of perturbative unitarity on the new physics interpretation of the anomalies in $b \to c \ell \bar \nu$ and $b \to…

High Energy Physics - Phenomenology · Physics 2017-10-10 Luca Di Luzio , Marco Nardecchia

In the pursuit of physics beyond the Standard Model, a promising path is the study of B-meson decays caused by the transition $b \to s\ell^+\ell^-$. A key observable in such decays is the ratio $R_K$, which measures electron--muon…

High Energy Physics - Phenomenology · Physics 2023-10-09 Robert Fleischer , Eleftheria Malami , Anders Rehult , K. Keri Vos

The increasing number of flavour anomalies motivates the investigation of new processes where tensions similar to the observed ones may emerge. It is necessary to identify observables sensitive to physics beyond the Standard Model. The…

High Energy Physics - Phenomenology · Physics 2022-09-20 Francesco Loparco

The decays governed by the flavor-changing-neutral-current transitions (FCNC), such as $b\to s\ell^{+}\ell^{-}$, provide an important tool to test the physics in and beyond the Standard Model (SM). This work focuses on investigating the…

High Energy Physics - Phenomenology · Physics 2024-09-02 Hira Waseem , Abdul Hafeez

In this article, we have predicted the standard model (SM) values of the asymmetric and angular observables in $B\to D^{(\ast)}\tau\nu_{\tau}$ decays, using the results of the new up-to-date analysis in $B\to D^{(*)}\ell\nu_{\ell}$. We have…

High Energy Physics - Phenomenology · Physics 2019-05-01 Srimoy Bhattacharya , Soumitra Nandi , Sunando Kumar Patra

We examine in detail the semi-leptonic decay $\Lambda_b \to \Lambda_c \tau{\bar \nu}_{\tau}$, which may confirm previous hints, from the analogous $B$ decay, of a new physics beyond the standard model. First of all, starting from rather…

High Energy Physics - Phenomenology · Physics 2018-10-16 E. Di Salvo , F. Fontanelli , Z. J. Ajaltouni

Recent experimental results on angular observables in the rare decay $B\to K^*\mu^+\mu^-$ show significant deviations from Standard Model predictions. We investigate the possibility that these deviations are due to new physics. Combining…

High Energy Physics - Phenomenology · Physics 2014-09-05 Wolfgang Altmannshofer , David M. Straub

We consider the exclusive decays $B \to D^{(*)}\,\ell \bar\nu$ and study the effect of non $V-A$ structures on the observables. We extend the standard model hadronic current by additional right-handed vector as well as left- and…

High Energy Physics - Phenomenology · Physics 2011-08-09 Sven Faller , Thomas Mannel , Sascha Turczyk

I review the recent theoretical progress on the study of tree-level semileptonic $b\to c$ decays. After briefly reviewing the latest developments on the exclusive determinations of $|V_{cb}|$, I discuss the hints on lepton flavor…

High Energy Physics - Phenomenology · Physics 2018-08-20 Olcyr Sumensari

Motivated by recent results from the LHCb, BABAR and Belle collaborations on B\to D^{(*)}\ell^-\bar{\nu}_\ell decays, which significantly deviate from the Standard Model and hint the possible new physics beyond the Standard Model, we probe…

High Energy Physics - Phenomenology · Physics 2016-06-01 Jie Zhu , Hua-Min Gan , Ru-Min Wang , Ying-Ying Fan , Qin Chang , Yuan-Guo Xu

Tests of lepton-universality as rate ratios in $b\to s \ell\ell$ transitions can be predicted very accurately in the Standard Model. The deficits with respect to expectations reported by the LHCb experiment in muon-to-electron ratios of the…

High Energy Physics - Phenomenology · Physics 2020-02-03 Li-Sheng Geng , Benjamín Grinstein , Sebastian Jäger , Jorge Martin Camalich , Xiu-Lei Ren , Rui-Xiang Shi

The study of $\bar{B} \to D^* \tau {\bar{\nu}}_\tau$ angular distribution can be used to obtain information about new physics (or beyond the Standard Model) couplings, which are motivated by various $B$ anomalies. However, the inability to…

High Energy Physics - Phenomenology · Physics 2026-04-17 Bhubanjyoti Bhattacharya , Thomas E. Browder , Alakabha Datta , Tejhas Kapoor , Emi Kou , Lopamudra Mukherjee

We study the exclusive $b \to u \ell^- \bar{\nu}_{\ell} (\ell=\tau,\mu,e)$ decays in the MSSM with and without R-parity violation. From the experimental measurements of branching ratios $\mathcal{B}(B^-_u \to \tau^- \bar{\nu}_{\tau})$,…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. S. Kim , Ru-Min Wang

Besides being important to determine Standard Model parameters such as the CKM matrix elements $|V_{cb}|$ and $|V_{ub}|$, semileptonic $B$ decays seem also promising to reveal new physics (NP) phenomena, in particular in connection with the…

High Energy Physics - Phenomenology · Physics 2018-06-19 Pietro Colangelo , Fulvia De Fazio

Decays of the kind $B^0_{s,d}\to\ell^+\ell^-$ belong to the most favourable processes for probing the flavour structure of the Standard Model, with outstanding sensitivity to new (pseudo)-scalar contributions. While the branching ratio of…

High Energy Physics - Phenomenology · Physics 2018-05-16 Robert Fleischer