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

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Rare decays of heavy-flavoured particles provide an ideal laboratory to look for deviations from the Standard Model, and explore energy regimes beyond the LHC reach. Decays proceeding via electroweak penguin diagrams are excellent probes to…

High Energy Physics - Experiment · Physics 2017-05-09 Simone Bifani

I review the signals for New Physics in CP-violating measurements in B and Lambda_b decays. I also discuss ways of identifying this New Physics, should such a signal be found.

High Energy Physics - Phenomenology · Physics 2011-07-19 David London

$B$ decays proceeding via $b\to c\ell\nu$ transitions with $\ell=e$ or $\mu$ are tree-level processes in the Standard Model. They are used to measure the CKM element $V_{cb}$, as such forming an important ingredient in the determination of…

High Energy Physics - Phenomenology · Physics 2019-01-30 Martin Jung , David M. Straub

Motivated by the recent theoretical and experimental developments in $b \to c \ell\nu$ transitions, the aim of these proceedings is to critically analyse the current situation in this sector. In particular, we will inspect the possibility…

High Energy Physics - Phenomenology · Physics 2024-04-01 Marco Fedele

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

The existence of New Physics particles can be probed by performing precision measurements of physics phenomena at the few GeV energy scale. The decays of B and D mesons are an excellent example of relatively low energy phenomena that can be…

High Energy Physics - Experiment · Physics 2019-08-14 A. Gaz

New physics effects in $B$ decays are routinely modeled through operators invariant under the strong and electromagnetic gauge symmetries. Assuming the scale for new physics is well above the electro-weak scale, we further require…

High Energy Physics - Phenomenology · Physics 2014-12-17 Rodrigo Alonso , Benjamin Grinstein , Jorge Martin Camalich

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

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

The semi-leptonic baryonic $b\to s$ decay, $\Lambda_b\rightarrow \Lambda \ell^+\ell^-$, has been studied and new angular observables and asymmetries have been proposed which can test the presence of new physics beyond the standard model.

High Energy Physics - Phenomenology · Physics 2015-11-04 Girish Kumar , Namit Mahajan

We investigate the angular distributions of the rare B decay, $B \to K^* (\to K \pi) \ell^+ \ell^-$, in general supersymmetric extensions of the standard model. We consider the new physics contributions from the operators $O_{7,8,9,10}$ in…

High Energy Physics - Phenomenology · Physics 2009-11-07 C. S. Kim , Yeong Gyun Kim , Cai-Dian Lu

In this letter we revisit the Standard Model predictions for $\mathcal{B}(B\to K^{(\ast)}\nu\bar{\nu})$ and discuss the opportunities that open up when combining its partial decay rate with that of $B\to K^{(\ast)}\ell\ell$. In the Standard…

High Energy Physics - Phenomenology · Physics 2023-04-10 Damir Bečirević , Gioacchino Piazza , Olcyr Sumensari

The $B$ meson semileptonic modes to $\rho(770)$ and $a_1 (1260)$ are useful to pin down possible non Standard Model effects. The 4d differential $\bar B \to \rho(\pi \pi) \ell^- \bar \nu_\ell$ and $ \bar B \to a_1 (\rho \pi) \ell^- \bar…

High Energy Physics - Phenomenology · Physics 2019-11-06 P. Colangelo , F. De Fazio , F. Loparco

We discuss the possibility of using the observables deduced from the angular distribution of the $B\to D^{(\ast)} \ell\bar{\nu}$ decays to test the effects of lepton flavor universality violation (LFUV). We show that the measurement of even…

High Energy Physics - Phenomenology · Physics 2019-07-16 Damir Becirevic , Marco Fedele , Ivan Nisandzic , Andrey Tayduganov

I summarize work done with Bamert, Burgess, Nardi and London in which we examine the effects of new physics on R_b. Our work facilitates the identification of such new physics in case the present two-sigma deviation of R_b from its Standard…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. M. Cline

It is well known that New Physics can contribute to weak decays of heavy mesons via virtual processes during its decays. The discovery of New Physics, using such decays is made difficult due to intractable strong interaction effects needed…

High Energy Physics - Phenomenology · Physics 2013-05-30 Diganta Das , Rahul Sinha

In $B_c^- \to J/\psi (\to \mu^+ \mu^-)\tau^-\bar{\nu}_\tau$ decay, the three-momentum $\boldsymbol{p}_{\tau^-}$ cannot be determined accurately due to the decay products of $\tau^-$ inevitably include an undetected $\nu_{\tau}$. As a…

High Energy Physics - Phenomenology · Physics 2021-06-30 Quan-Yi Hu , Xin-Qiang Li , Xiao-Long Mu , Ya-Dong Yang , Dong-Hui Zheng

In this work we study the effects of new-physics (NP) operators with different Lorentz structures on the inclusive $B \to X_c\tau \bar{\nu}$ decay and make predictions for the ratio of total decay rates $R(X_c)=\frac{\Gamma(B \to X_c\tau…

High Energy Physics - Phenomenology · Physics 2018-05-31 Saeed Kamali , Ahmed Rashed , Alakabha Datta

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

In this work, we study the decays $\Lambda_c \to (\Lambda, n) \ell^+ \nu_\ell$ ($\ell = \mu, e$) within a model-independent framework. We calculate the helicity amplitudes for all possible four-fermion operators, including the interactions…

High Energy Physics - Phenomenology · Physics 2025-01-23 Zhi-Hua Zhang , Ying Li