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Related papers: Asymmetry Observables and the Origin of $R_{D^{(*)…

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$B$ physics plays important roles in searching for the new physics (NP) beyond the standard model (SM). Recently, some deviations between experimental data and SM predictions were reported, namely $R(D^{(*)})$, $P_5^\prime$ and…

High Energy Physics - Phenomenology · Physics 2018-08-10 Ying Li , Cai-Dian Lu

The first observation of $\mathcal{B}\left(B^+\rightarrow K^+\nu\nu\right)$ by the Belle II experiment lies almost $3\sigma$ away from the Standard Model expectation. In this letter we study this result in the SMEFT, extended by a light…

High Energy Physics - Phenomenology · Physics 2024-08-28 L. P. S. Leal , S. Rosauro-Alcaraz

Motivated by the persistent anomalies reported in the $b\to c\tau\bar{\nu}$ data, we perform a general model-independent analysis of these transitions, in the presence of light right-handed neutrinos. We adopt an effective field theory…

High Energy Physics - Phenomenology · Physics 2020-08-11 Rusa Mandal , Clara Murgui , Ana Peñuelas , Antonio Pich

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

It is experimentally observed that ratios of branching fractions for semitauonic and semileptonic $B$ decays, known as the $R(D^{(*)})$, are higher than Standard Model (SM) predictions. The $B \to \bar{D}^{(*)} \tau^{+} \nu_{\tau}$ decays,…

High Energy Physics - Experiment · Physics 2019-01-28 Karol Adamczyk

In this paper, we present the differential decay distributions for $\bar B \to D^{(*)} \ell \bar{X}$ decays with a massive right-handed neutrino in the low-energy effective field theory framework and show how the massive effects of the RH…

High Energy Physics - Phenomenology · Physics 2022-08-02 Hongkai Liu

We point out that right-handed neutrinos can resolve the tension between the latest CDF II measurement of the $W$-boson mass, $M_W$, and the standard model. Integrating out the new states yields a single $d=6$ operator, which induces a…

High Energy Physics - Phenomenology · Physics 2022-05-04 Mattias Blennow , Pilar Coloma , Enrique Fernández-Martínez , Manuel González-López

Recent experimental measurements of several observables in semileptonic B meson decays have pointed towards the possibility of new physics. The LHCb collaboration has reported a significant deviation, exceeding $3.2\sigma$, in the combined…

High Energy Physics - Phenomenology · Physics 2026-02-04 Nilakshi Das , Amit Adhikary , Rupak Dutta

An interesting possibility to ease the tension between various determinations of |V_{ub}| is to allow a small right-handed contribution to the standard model weak current. The present bounds on such a contribution are fairly weak. We…

High Energy Physics - Phenomenology · Physics 2014-11-11 Florian U. Bernlochner , Zoltan Ligeti , Sascha Turczyk

Within the assumption of Left-Handed (LH) New Physics (NP), we review the relations between $\mathcal{B}(B\to K^{(\ast)} \tau^+\tau^-)$ and $\mathcal{B}(B\to K^{(\ast)} \nu\bar \nu)$ for several Beyond the Standard Model (BSM) scenarios,…

High Energy Physics - Phenomenology · Physics 2022-11-11 Arturo de Giorgi , Gioacchino Piazza

We present an ultraviolet complete theory for the $R(D^*)$ and $R(D)$ anomaly in terms of a low mass $W_R^\pm$ gauge boson of a class of left-right symmetric models. These models, which are based on the gauge symmetry $SU(3)_c \times…

High Energy Physics - Phenomenology · Physics 2019-02-20 K. S. Babu , Bhaskar Dutta , Rabindra N. Mohapatra

Experimental measurements collected by the BABAR, Belle, and LHCb experiments on different observables associated with the semileptonic transition $b \to c \tau \bar{\nu}_\tau$, indicate the existence of disagreement respect with the…

High Energy Physics - Phenomenology · Physics 2021-05-13 Jonathan Cardozo , J. H. Muñoz , Nestor Quintero , Eduardo Rojas

Scalar theories can account for the current $R_{D^{(*)}}$ measurements through a vector operator $\bar{c}_L \gamma_{\mu} b_L\,\bar{\tau}_L \gamma^{\mu}\nu_L$ induced at the loop level. Once the vector contribution is considered on top of a…

High Energy Physics - Phenomenology · Physics 2019-09-25 Carlo Marzo , Luca Marzola , Martti Raidal

We develop a rigorous, semi-analytical method for maximizing any $b\to c\tau\nu$ observable in the full 20-real-dimensional parameter space of the dimension 6 effective Hamiltonian, given some fixed values of $R_{D^{(*)}}$. We apply our…

High Energy Physics - Phenomenology · Physics 2019-12-11 Pouya Asadi , David Shih

We calculate the complete differential decay distributions for the $B$ meson decays, $\bar B \to D^{(*)} \ell \bar{X}$, to a massive right-handed (RH) neutrino in the low-energy effective field theory (LEFT) framework. We find that a…

High Energy Physics - Phenomenology · Physics 2023-08-17 Alakabha Datta , Hongkai Liu , Danny Marfatia

The Belle II experiment will measure the rare decays $B\to K\nu\nu$ and $B\to K^* \nu\nu$ with increased sensitivity which can hence be expected to serve as a very efficient probe of new physics. We calculate the relevant branching ratios…

High Energy Physics - Phenomenology · Physics 2021-12-21 Tobias Felkl , Sze Lok Li , Michael A. Schmidt

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 assess the ability of the Belle II experiment to probe the Dirac or Majorana nature of a massive right-handed neutrino (RHN) $N$ in the MeV to GeV mass range. We consider the production and decay of RHNs to proceed via new interactions…

High Energy Physics - Phenomenology · Physics 2025-07-29 Tao Han , Jiajun Liao , Hongkai Liu , Danny Marfatia

We consider the phenomenology of the gauged abelian symmetry B + 3 (L_e - L_mu - L_tau). Right-handed neutrinos necessary to cancel triangle anomalies are used in a type-I seesaw scheme to create active neutrino masses. Breaking the B + 3…

High Energy Physics - Phenomenology · Physics 2012-06-28 Julian Heeck , Werner Rodejohann

We consider the possibility to explain the recent $R_K$ and $R_{K ^*}$ anomalies in a 2-Higgs Doublet Model, known as Aligned, combined with a low scale seesaw mechanism generating light neutrino masses and mixings. In this class of models,…

High Energy Physics - Phenomenology · Physics 2020-07-01 Luigi Delle Rose , Shaaban Khalil , Simon J. D. King , Stefano Moretti
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