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Related papers: New physics effects in tree-level decays

200 papers

The persisting anomalous data in semileptonic B-decays point towards New Physics models exhibiting large sources of Lepton Flavour Universality Violation. In this work we generalise previous studies by considering frameworks which include…

High Energy Physics - Phenomenology · Physics 2018-11-14 Claudia Cornella , Ferruccio Feruglio , Paride Paradisi

The LHCb approach for a precise determination of the CKM angle $\gamma$ from tree--level decays is presented. Up to 16 independent determinations, using a variety of beauty and charm mesons decay modes, are available at LHCb. Not all of…

High Energy Physics - Experiment · Physics 2019-06-21 A. Bertolin

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

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

The $B^0_s\to D_s^\mp K^\pm$ system offers a determination of the Unitarity Triangle angle $\gamma$. Intrigued by an LHCb analysis showing a surprisingly large result in tension with information on the Unitarity Triangle and other $\gamma$…

High Energy Physics - Phenomenology · Physics 2023-05-23 Robert Fleischer , Eleftheria Malami

The standard CKM model can be tested and New Physics detected using only CP-violating phase measurements in B decays. This requires the measurement of a phase factor which is small in the Standard Model, in addition to the usual large…

High Energy Physics - Phenomenology · Physics 2016-09-06 Joao P. Silva , L. Wolfenstein

Based on the low energy effective Hamiltonian with generalized factorization, we calculate the new physics contributions to the branching ratios and CP-violating asymmetries of the two-body charmless hadronic decays $B \to PP, PV$ from the…

High Energy Physics - Phenomenology · Physics 2009-01-07 Zhenjun Xiao , Wenjun Li , Libo Guo , Gongru Lu

We study extensions of the Standard Model where the charged current weak interactions are governed by the CKM matrix and where all tree-level decays are dominated by their Standard Model contribution. We constrain both analytically and…

High Energy Physics - Phenomenology · Physics 2014-11-17 Sven Bergmann , Gilad Perez

As we pointed out recently, the neutral decays $B_d\to\pi^\mp K^\pm$ and $B_d\to\pi^0K$ may provide non-trivial bounds on the CKM angle $\gamma$. Here we reconsider this approach in the light of recent CLEO data, which look very…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrzej J. Buras , Robert Fleischer

We study the influence of penguin (especially, electroweak penguin) effects on some methods of measuring the angles $\alpha$, $\beta$, and $\gamma$ in the CKM unitarity triangle. We use next-to-leading order effective Hamiltonian, and…

High Energy Physics - Phenomenology · Physics 2010-11-23 N. G. Deshpande , Xiao-Gang He , Sechul Oh

The CP asymmetry in inclusive B->X_{s,d}+gamma decays is an important probe of new physics. The theoretical prediction was thought to be of a perturbative origin, and in the standard model, to be about 0.5 percent. In a recent work with M.…

High Energy Physics - Phenomenology · Physics 2012-06-18 Gil Paz

Using the $SU(3)$ flavour symmetry of strong interactions, we propose strategies for extracting both the CKM-angle $\gamma$ and the $\bar b\to\bar uu\bar s$ tree-level amplitude $T'$. We present also an approximate approach using the…

High Energy Physics - Phenomenology · Physics 2011-01-05 Robert Fleischer

We study inclusive semileptonic $\bar{B}\to X_c \ell \bar{\nu}$ decays ($\ell = e,\mu$) in the presence of generic physics Beyond the Standard Model (BSM) that is heavy compared to the $b$-quark mass. Its effect is encoded in the Wilson…

High Energy Physics - Phenomenology · Physics 2025-09-01 Alexandre Carvunis , Gael Finauri , Paolo Gambino , Martin Jung , Sandro Mächler

The study of CP violation in $B$-meson decays has already reached a high level of precision, which will be pushed even higher in the future era of Belle-II and the LHCb upgrade. %Important probes of CP violation are the $B_d^0$ and $B_s^0$…

High Energy Physics - Phenomenology · Physics 2018-07-24 K. Keri Vos

We devise tests for a new physics origin of the recently measured direct CP violation in singly Cabibbo suppressed D decays. The tests take the form of sum rules for the CP asymmetries in various D decays. They are based on the fact that…

High Energy Physics - Phenomenology · Physics 2015-06-04 Yuval Grossman , Alexander L. Kagan , Jure Zupan

We investigate new physics effects on $B\to D^{(*)}\tau\nu$ decays in a general and model-independent way. The $\chi^2$ fits for fractions of the branching ratios $R(D^{(*)})$ and other polarization parameters are implemented. We…

High Energy Physics - Phenomenology · Physics 2025-03-13 Jong-Phil Lee

With updated experimental data and improved theoretical calculations, several significant deviations are being observed between the Standard Model predictions and the experimental measurements of the branching ratios of $\bar{B}_{(s)}^0\to…

High Energy Physics - Phenomenology · Physics 2021-11-17 Fang-Min Cai , Wei-Jun Deng , Xin-Qiang Li , Ya-Dong Yang

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 perform a global fit to the CKM unitarity triangle using the latest experimental and theoretical constraints. We present results for three different sets of constraints: the standard inputs used by CKMfitter and UTFit, the standard…

High Energy Physics - Phenomenology · Physics 2011-11-10 Jack Laiho , Enrico Lunghi , Ruth Van De Water

A recent analysis of $B \to \pi K$ decays concludes that present data do not clearly indicate whether (i) the standard model (or $\Delta I=0$ new physics) is sufficient, or (ii) $\Delta I=1$ new physics is needed. We show that these two…

High Energy Physics - Phenomenology · Physics 2009-07-29 Seungwon Baek , Cheng-Wei Chiang , Michael Gronau , David London , Jonathan L. Rosner