English
Related papers

Related papers: Prospects for New Physics searches with $\Lambda_b…

200 papers

The flavor-changing neutral current semileptonic decays of $B$ mesons provide an excellent platform for indirectly probing New Physics (NP) beyond the Standard Model (SM). Recent measurements of lepton flavor universality (LFU) ratios such…

High Energy Physics - Phenomenology · Physics 2026-01-08 Md Isha Ali , Utpal Chattopadhyay , Dilip Kumar Ghosh , N Rajeev

We carry out an analysis of the multibody decay cascade $\Lambda_b\to \Lambda^*_J J/\psi \to pK^- J/\psi$ with the $ \Lambda^*_J$ resonance including $\Lambda^*_{1520},\Lambda^*_{1600}$, and $\Lambda^*_{1800}$, and $J/\psi$ reconstructed by…

High Energy Physics - Phenomenology · Physics 2022-11-22 Zhi-Peng Xing , Fei Huang , Wei Wang

We discuss the possibility that light new physics in the top quark sample at the LHC can be found by investigating with greater care well known kinematic distributions, such as the invariant mass $m_{b\ell}$ of the $b$-jet and the charged…

High Energy Physics - Phenomenology · Physics 2023-12-18 Emanuele Bagnaschi , Gennaro Corcella , Roberto Franceschini , Dibyashree Sengupta

The measurements of several lepton flavor universality (LFU) violating observables in the decays induced by the quark level transition $b \to c \tau \bar{\nu}$ provide an inkling of plausible physics beyond the standard model of electroweak…

High Energy Physics - Phenomenology · Physics 2023-05-17 Shabana Khan , Neetu Raj Singh Chundawat , Dinesh Kumar

We present results of global fits of all relevant experimental data on rare $b \to s$ decays. We observe significant tensions between the Standard Model predictions and the data. After critically reviewing the possible sources of…

High Energy Physics - Phenomenology · Physics 2015-09-30 Wolfgang Altmannshofer , David M. Straub

We investigate the experimentally-accessible kinematic distributions of the $\bar B\to D^{(*)}\tau^-(\to\ell^-\bar\nu_\ell\nu_\tau)\bar\nu_\tau$ decays. Specifically, we study the decay rates as functions of the $B\to D^{(*)}$ transferred…

High Energy Physics - Phenomenology · Physics 2016-11-23 Rodrigo Alonso , Andrew Kobach , Jorge Martin Camalich

Motivated by the first observation of $\Lambda_b\to\Lambda_c~\tau\bar{\nu}$ by LHCb, we discuss various observables that can be derived from angular distribution of this decay which, if measured, could be essential for explanation of the…

High Energy Physics - Phenomenology · Physics 2022-10-24 Damir Becirevic , Florentin Jaffredo

We investigate the $\Lambda_c \to \Lambda \ell^{+} \nu_\ell$ decay with a focus on potential new physics (NP) effects in the $\ell = \mu$ channel. We employ an effective Hamiltonian within the framework of the Standard Model Effective Field…

High Energy Physics - Phenomenology · Physics 2024-09-16 Fernando Alvarado , Luis Alvarez-Ruso , Eliecer Hernandez , Juan Nieves , Neus Penalva

This article analyses the available inputs in $\btopilnu$ and $\btorholnu$ decays which include the measured values of differential rate in different $q^2$-bins (lepton invariant mass spectrum), lattice, and the newly available inputs on…

High Energy Physics - Phenomenology · Physics 2021-10-04 Aritra Biswas , Soumitra Nandi

In the Standard Model, the photon emitted in b->s\gamma decays is predicted to be left-handed polarized. We discuss the types of New Physics which can produce a deviation from this prediction, focusing on the Minimal Supersymmetric Standard…

High Energy Physics - Phenomenology · Physics 2007-05-23 Dan Pirjol

We present a full angular distribution of the four body $\Lambda_b\to\Lambda(\to N\pi)\ell^+\ell^-$ decay where the leptons are massive and the $\Lambda_b$ is unpolarized, in an operator basis which includes the Standard Model operators,…

High Energy Physics - Phenomenology · Physics 2018-08-01 Diganta Das

The lepton polarization asymmetry in the B\to\ell^{+}\ell^{-} decay, when one of the leptons is polarized, is investigated using the most general form of the effective Hamiltonian. The sensitivity of the asymmetry to the new Wilson…

High Energy Physics - Phenomenology · Physics 2009-11-10 V. Bashiry

We explain recent LHCb measurements of the lepton universality ratios, $R_{D^{(*)}}^{\tau/\ell}\equiv \frac{\mathcal{B}(\bar B \to D^{(*)+} \tau^- \bar\nu_\tau)} {\mathcal{B}(\bar B \to D^{(*)+}\ell^- \bar\nu_\ell)}$ and…

High Energy Physics - Phenomenology · Physics 2024-06-05 Alakabha Datta , Danny Marfatia , Lopamudra Mukherjee

We examine the $q^2$-binned distributions of the $D\to K\mu\nu$ decay rate and of the corresponding forward-backward asymmetry which were recently measured by BESIII, showing a mild deviation from the Standard Model predictions. We point…

High Energy Physics - Phenomenology · Physics 2026-03-30 D. Bečirević , M. Martines , S. Rosauro-Alcaraz , O. Sumensari

The rare $B \to K^{(*)} \bar{\ell} \ell$ decays exhibit a long-standing tension with Standard Model (SM) predictions, which can be attributed to a lepton-universal short-distance $b \to s \bar{\ell} \ell$ interaction. We present two novel…

High Energy Physics - Phenomenology · Physics 2023-11-03 Arianna Tinari

It has been shown that the anomalies observed in $\bar B\to D^{(\ast)}\tau\bar\nu_\tau$ and $\bar B\to \bar K\ell^+\ell^-$ decays can be resolved by adding a single scalar or vector leptoquark to the Standard Model, while constraints from…

High Energy Physics - Phenomenology · Physics 2017-03-08 Xin-Qiang Li , Ya-Dong Yang , Xin Zhang

Motivated by deviations with respect to Standard Model predictions in $b\to s\ell^+\ell^-$ decays, we evaluate the global significance of the new physics hypothesis in this system by including the {\it look-elsewhere effect} for the first…

High Energy Physics - Phenomenology · Physics 2021-09-28 Gino Isidori , Davide Lancierini , Patrick Owen , Nicola Serra

Lepton universality, meaning the equal coupling of the electroweak gauge bosons to the different lepton flavours, is a central property of the Standard Model (SM). Tests of lepton universality in ratios of rates of $b\to s\ell^+\ell^-$…

High Energy Physics - Experiment · Physics 2023-05-19 Christoph Langenbruch

Intriguing results for tests of the universality of electrons and muons through measurements of rates of $B\to K \ell^+ \ell^-$ and similar decays have been in the spotlight for years. The LHCb collaboration has recently reported new…

High Energy Physics - Phenomenology · Physics 2023-06-21 Robert Fleischer , Eleftheria Malami , Anders Rehult , K. Keri Vos

Flavour-changing neutral-current processes, such as $b\to s \ell^+\ell^-$, are forbidden at tree level in the Standard Model and hence might receive comparatively large corrections from new particles. This document highlights recent…

High Energy Physics - Experiment · Physics 2023-03-22 M. Santimaria